by
RONALD PROKOPY AND STARKER WRIGHT
DEPARTMENT OF ENTOMOLOGY, UNIVERSITY OF MASSACHUSETTS
GLENN MORIN
NEW ENGLAND FRUIT CONSULTANTS
KATHLEEN LEAHY
POLARIS ORCHARD MANAGEMENT
INTRODUCTION Since its inception, the intent of the March Message has been to summarize new information and offer thoughts related to the management of insect and mite pests in Massachusetts. The March Message is not considered to be a publication, thus allowing the expression of opinion that might be withheld from a formal publication.
GENERAL IPM TOPICS AND OPINION
PROBLEM PESTS: ACTIVITY, NEW FINDINGS AND TECHNOLOGIES
IPM MANUALS, SUPPLIES AND SERVICES
Over the past several years, progress toward registration of new agricultural chemicals has slowed substantially as the focus of the EPA has shifted toward careful consideration of label changes for organophosphates as dictated by the FQPA. With uncertainty surrounding the continued practical use of some common chemicals, many companies have placed an emphasis on development of materials that may stand as new-generation substitutes for some of the flexible uses of OPs. In the past year, several new chemicals (some with very new chemistries and modes of action) and a few older materials have made strides toward registration for use on tree fruit in Massachusetts.
Esteem (pyriproxyfen) received full federal registration for use on apples and pears in the fall of 1999. This material is classified as an insect growth regulator, and is only known to be effective as an egg-growth suppressant. It has been labeled for use on cotton for a number of years (under the trade name Knack) and is now labeled on apples and pears for use against codling moth, leafroller, aphids, San Jose scale, and leafminer-data from recent use under a Section 18 permit in Washington and Oregon suggest that it is most effective against scale insects. Although this material has demonstrated translaminar foliar residual activity, efficacy against leafminer is not fully established, and it is not yet clear whether it will impact development of early- to mid-instar larvae as well as eggs, which is critical in a scouting-based LM management program. Cost may be somewhat prohibitive to trial use; early estimates indicate that label-rate use will run roughly $75 per acre.
After many years of regional trials, Confirm (tebufenozide) received both federal labeling and state approval for use on pome fruit for the 2000 season. This material is labeled against a wide range of lepidopteran pests (including codling moth, leafroller, lesser appleworm, and green fruitworm), and works by inducing premature molting of developing leps-killing the target pest but few nontarget individuals. As is the case with many new-generation insecticides, this material is most effective when consumed by the target insect, so thorough coverage is necessary for consistent pest control. Intrepid (methoxyfenozide) is a chemical variant of Confirm, and shares its mode of action. Federal registration of this material is anticipated during the spring of 2000; the pest management activity is similar to that of Confirm, though Intrepid has demonstrated suppression of tentiform leafminers in addition to direct leps.
Danitol (fenpropathrin), classified as a Type I and Type II synthetic pyrethroid, received full federal registration for use on apples, pears, and grapes earlier this month, though state approval is still pending. Like most pyrethroids, Danitol offers broad-spectrum arthropod control, and is labeled for use pre-bloom, post-bloom, or late season (with a 14 day preharvest interval). Interestingly, this material is labeled for use against European red mites and two-spotted spider mites, though it is also known to kill most beneficials in the bargain. It is likely that this material will be of most value as a prebloom treatment or for use in areas with OP resistance problems. No more than 2 applications per season are recommended, and resistance development is a major concern. It is a fairly inexpensive material, costing $12-15 at the labeled rate of ~16 oz. per acre.
Surround (kaolin clay) Crop Protectant represents a new technology for use in apple orchards: particle barrier film. A sprayed application of the clay (at 25 lbs. per 100 gallons) dries to form a thin, white particle residue on fruit and foliage, barring tissues from a wide range of insect and disease pests, enhancing growth, and protecting fruit and foliage from heat stress. Although this material is labeled as a nearly all-encompassing season-long crop protector, it has not yet demonstrated effectiveness against aphids, San Jose scale, or mites. However, Surround may offer a potential leap forward for nonlethal control of many other apple pests, notably apple maggot, plum curculio, codling moth, leafrollers, leafhoppers, and thrips. In addition, this material was recently listed by the Organic Materials Review Institute as acceptable for use in organic production. That said, this technology will undergo some broader local trials this season to more fully understand its potential for use in IPM programs.
Actara (thiamethoxam) is a second-generation neonicotinoid compound which is slated to receive Section 3 (full federal) labeling for pome fruit in late summer of 2000. This material has demonstrated efficacy against aphids, leafhoppers, and pear psylla; trials are ongoing toward development of use protocols for sawfly, leafminer, and plum curculio.
Avaunt (indoxacarb) represents a new chemistry (oxadiazine-a sodium channel blocker) broad-spectrum insecticide. This material is touted as a potential OP replacement; under evaluation, Avaunt demonstrated control of plum curculio, nearly all lep pests, tarnished plant bug, sawfly, and leafhoppers. It is unlikely that this material will be available for use in Massachusetts in the 2000 growing season (full registration is still pending), but it does hold potential as a relatively soft, flexible chemical management tool for use in the near future.
There are several materials that have been in the product development and registration pipeline for many years that will remain there for the foreseeable future. For example, Comply (fenoxycarb) was initially developed as a growth regulator with a scope of activity similar to Confirm (above). However, in 1999 it was classified as a carbamate, and has encountered consistent registration hurdles since. According to the manufacturer, it is unlikely that this material will be registered for use on apple anytime soon.
Last year, it appeared that Pennstyl (cyhexatin-formerly sold as Plictran) was being placed on the EPA fast track toward registration as a resistance management tool for control of European red mites on apple. This material received a Section 18 emergency registration for use on hops in Washington and Oregon in 1999, and it appears that the registration emphasis will be on hops and small fruit in 2000 and 2001. Decisions on these crops will be made in mid-March 2000, and use on pome fruit will not be considered for registration until 2002.
Certainly a great majority of the chemical registration debate in 1999 revolved around continued use of Guthion and other OPs on tree fruit. When the dust had settled (if it has indeed settled), the principal label change on Guthion was an increase in preharvest interval to 14 days (21 days if the final application = 16 oz. (a.i.) per acre or more). The reentry interval was increased to 14 days as well (from the previous 48-72 hour interval) for certain activities, such as hand thinning, propping, and pruning. For scouting, mowing, and other less contact-intensive activities, the REI remains at 48 hours. However, the situation surrounding continued practical use of Guthion and a few other major chemicals is consistently evolving.
In 1997, we launched the first of two 3-year phases of research on third-level IPM practices in grower orchards. Third-level IPM aims at integration of all pest management practices with all horticultural practices.
Why do we in Massachusetts devote a large amount of energy attempting to establish simple, effective and economical pest management practices under the concept of third-level IPM? We do so for 4 main reasons. First, new regulations under FQPA may restrict future use of organophosphates and other familiar pesticides, thereby leaving a potentially serious gap in our ability to manage several key pests effectively. Third-level IPM offers promise of biologically based methods of control that could help fill this gap. Second, many other apple-growing regions of North America and many other apple-producing countries (especially in Europe) are in the process of developing advanced-level IPM practices that will permit their apples to be sold under some sort of "green label." Apples from Massachusetts intended for export that do not meet "green label" requirements may be excluded from some international marketplaces. Third, for Massachusetts growers who sell their apples at roadside stands, farmers' markets or as pick-your-own, it could be a distinct benefit to be recognized by customers as a grower who is highly conscious of the value of healthy fruit and a healthy environment. Fourth, federal grant funds are becoming increasingly restricted to supporting research and demonstration efforts that focus only on advanced forms of IPM. If we fail to obtain federal grant funds, Massachusetts will cease to have a viable IPM research and demonstration program for apples. Research on all levels of IPM will become severely restricted.
Several findings of the first 3-year phase (1997-1999) of research under third-level IPM are given below. This phase aimed primarily at studying the influence of apple tree architecture (particularly tree size) on effectiveness of biologically based approaches to controlling 4 important apple pests: plum curculio, flyspeck, apple maggot and mites. The second 3-year phase (2000-2002) aims largely at studying the effect of apple orchard architecture (particularly cultivar choice and arrangement) on bio-based approaches to managing these same 4 pests. Both tree architecture and orchard architecture are essential components of horticultural practice and both have a potentially powerful impact on the degree to which bio-based pest management techniques can succeed.
The 1997-1999 third-level IPM project involved studies in 48 blocks of apple trees across 8 commercial orchards. Each block was approximately square: 7 trees per row x 7 rows. Of the 48 blocks, 16 each were comprised of large (M.7), medium (M.26) and small (M.9) trees. Of the 16 blocks of each tree size, 8 were under bio-based management to the maximum possible extent and 8 were under first-level IPM management.
Also given below are additional findings from our 1999 research that complement findings under third-level IPM research, including results of a study on leafminer species composition and buildup.
Among key insect pests that attack pome and stone fruit in North America, plum curculio (PC) is the only one for which there does not yet exist an effective monitoring trap. In 1995, we began in earnest to conduct research aimed at developing such a trap. Here, we present a summary of findings from 3 principal lines of field research conducted in 1999. Full reports on each of these aspects, plus findings from lab studies, are given in the next issue of Fruit Notes.
Commercial-Orchard Trials of Traps for Monitoring PC. In the aforementioned 48 blocks of trees in 8 commercial orchards, we evaluated 3 types of traps: (a) black pyramid traps (24 inches wide at base x 48 inches tall) placed on the ground next to apple tree trunks, (b) black cylinder traps (3 inches diameter x 12 inches tall) fixed vertically onto horizontal branches within apple tree canopies, and (c) aluminum-screen "circle" traps (developed in Oklahoma for pecan weevils) and wrapped tightly around ascending tree limbs, designed to intercept PC adults walking upward. Traps were placed in 6 blocks of apple trees in each orchard. Each block consisted of 7 perimeter trees. Each tree (save one) contained 1 unbaited and 1 baited trap of the above types. The bait consisted of a combination of 1 polyethylene vial containing limonene and 2 polyethylene vials containing ethyl isovalerate (components of host fruit odor found to be attractive to PCs in 1998 studies) plus 1 rubber septum impregnated with grandisoic acid (attractive male-produced pheromone of PC). Vials were attached to the exterior of traps at mid height and the septum was placed inside the inverted wire-screen funnel (boll weevil trap top) that capped each trap and captured responding PCs. All traps were deployed at bloom and were examined for captured PCs every 3-4 days for 6 weeks thereafter. At each trap examination, 15 fruit on each of the seven trees per block were examined for PC oviposition scars. All blocks received two grower-applied sprays of azinphosmethyl to control PC.
Significantly more (about 3 times more) total PCs were captured by pyramid traps than by cylinder traps, with circle traps capturing no PCs. There was no significant difference in captures between unbaited and baited traps of any type. Disappointingly, none of the three types of baited or unbaited traps yielded captures whose amounts or phenology (pattern of occurrence over time) reflected even in a very minimal way the amount or phenology of egglaying injury to fruit caused by PC. If there were a perfect relationship, a value termed R2 would equal 1.00. Here, the R2 value describing the relationship between abundance of PCs in traps and amount of injury never exceeded 0.14 for any unbaited or baited trap, and the R2 value describing relationship between time of capture of PCs in traps and time of injury did not exceed 0.06 for any type of unbaited or baited traps.
The fact that a large amount of effort went into this commercial-orchard experiment and the fact that rather little progress toward development of an effective trap came from it is sobering. Progress in research often comes in spurts. We are hopeful that our PC studies in commercial orchards in 2000 will be more rewarding.
Unsprayed-Orchard Trials of Traps for Monitoring PC. In 3 small unsprayed orchards, we evaluated unbaited and baited above-type pyramid and cylinder traps as well as clear Plexiglas squares (2 feet x 2 feet) fastened vertically 5 feet above ground to wooden poles seated in the ground. One side of each Plexiglas square was coated with Tangletrap to capture alighting PCs. Plexiglas traps were positioned with sticky-side facing woods either 6 feet from the edge of the woods or 1 foot outside of perimeter foliage of apple trees. Traps were placed in 4 blocks of apple trees in each orchard. Each block consisted of 6 perimeter trees. Each tree contained 1 unbaited and 1 baited trap (above type bait) of each trap type. Each block in 2 of the orchards also received 1 unbaited and 1 baited clear Plexiglas trap placed at the edge of the woods. All traps were emplaced at bloom. Every 3-4 days thereafter for 6 weeks, traps were examined for captured PCs and fruit were examined for PC scars. No insecticide was applied to any of the blocks.
Significantly more (about 8 times more) PCs were captured by pyramid traps than by cylinder traps, with clear Plexiglas traps positioned next to apple trees capturing slightly but not significantly more PCs than cylinder traps. Captures by unbaited versus baited traps did not differ significantly for any of these 3 trap types. However, baited clear Plexiglas traps placed at the edge of woods did capture significantly more PCs (about 14 times more) than similarly positioned unbaited traps. In contrast to above findings in commercial orchards, R2 values describing relationship between abundance of PCs in traps and amount of injury ranged between 0.56-0.80 for unbaited and baited pyramid traps and clear Plexiglas traps placed next to perimeter apple trees. Less encouraging, however, were R2 values describing relationship between time of capture of PCs in traps and time of injury, which did not exceed 0.05 for any type of unbaited or baited trap.
We feel more encouraged by results of these studies in unsprayed orchards than by results from commercial-orchard tests. For some unknown reason, there was a much better correlation between amount of captured PCs by pyramid traps and amount of fruit injury in unsprayed than in commercial orchards. We found this to be true also in 1998. Because it is in commercial orchards (not unsprayed orchards) that PC traps will have major practical use, we can not feel satisfied until traps perform better in commercial orchards.
We feel quite encouraged by the finding that PCs responded positively to clear Plexiglas traps placed next to woods. In the future, a simpler and more attractive version of this type of baited trap could be very useful for monitoring the beginning, peak and (most importantly) the end of immigration of overwintered PCs from woods or hedgerows into orchards.
Evaluation of Attractiveness of Different Compounds from Host Odor. To date, 57 compounds have been identified as components of odor of plum or apple fruit at the most attractive stage to PC (2 weeks after bloom). Last year, we presented results of 1998 tests evaluating 16 of these 57 compounds for attractiveness to PC. In 1999, we re-evaluated these 16 compounds plus an additional 14 compounds: the 30 compounds were the most readily available from a commercial source and least expensive to purchase.
Each compound was introduced into a 2-dram polyethylene vial and assessed at 3 different rates of odor release, so as to create a low, moderate or high dose of odor concentration in the surrounding air. Release rates were varied either by adding mineral oil to the contents of a vial to reduce release rate or drilling small holes in a vial just beneath the cap to increase release rate. Intended release rates for each compound were 3, 12, and 48 milligrams of odor per day, but it was not always possible to achieve intended precision with each compound.
Compounds were assayed in association with yellow-green boll weevil traps placed on the ground beneath perimeters of unsprayed apple tree canopies in Massachusetts and Ohio. PCs frequently drop from host tree canopies to the ground and thus may encounter odor from a nearby baited trap. Each trap was baited either with a vial containing one compound or an empty vial. Vials were suspended vertically by wire attached to the base of the screen funnel top of the trap. Over a 7-week period from early May to late June, 360 traps were deployed in Ohio and another 360 in Massachusetts for compound evaluation. Traps were examined for captured PCs and rotated in position daily or every other day.
To measure attractiveness of a particular release rate of a particular compound, a Response Index (RI) was created. If a baited trap were 2 times as attractive as an unbaited trap, RI = 32. If 3 times, RI = 50. If 4 times, RI = 60.
Results showed that 13 of the 30 compounds had RI values of 32 or greater at the most attractive release rate. In descending order of attractiveness, these were E-2-hexenal (RI=90), hexyl acetate (67), decanal (64), limonene (64), geranyl propionate (59), 1-pentanol (59), benzaldehyde (46), benzyl alcohol (44), ethyl isovalerate (40), 2-pentanol (35), 2-hexanol (32), phenylacetaldehyde (32), and 2-propanol (32).
Several new compounds thus proved as attractive to PC as the most attractive compound (limonene) found in 1998 tests. Just as important, these results give us good insight into the amount of compound (release rate) that may be most attractive. To humans, a scent may be undetectable at too low a concentration, and repellent at too high a concentration. The same is true for insects. In fact, these 1999 results suggest that the amount of ethyl isovalerate we used in aforementioned trap comparisons in commercial and unsprayed orchards was probably too great and therefore repellent, canceling out the attractiveness of the other host odor used (limonene).
Overall, we are very encouraged by these 1999 findings of PC response to host odor compounds. There is now much promise that one or more of these attractive compounds alone (or together in a blend) at an appropriate release rate can be applied to one or more of the above trap types to substantially enhance trap effectiveness.
Future Plans on PC. In 2000, we plan to evaluate the 6 most attractive host odor compounds found in 1999 in combination with a new and improved source and formulation of PC sex pheromone. Evaluations will occur in conjunction with the same trap types tested in 1999, and in commercial as well as unsprayed orchards. We also plan to more intensively evaluate the 13 most attractive compounds found in 1999 (and blends of them) plus 7 new (not yet evaluated) compounds comprising host fruit odor.
Apple maggot flies (AMF) build to high populations on millions of unmanaged wild apple and hawthorn trees from which they invade orchards in July, August and September. Several previous years of research have shown that surrounding large blocks of medium-size apple trees with odor-baited sticky red spheres (5 yards apart) to intercept immigrating AMF can provide control nearly (but not quite) equal to control provided by 3 insecticide sprays. If traps are to become a feasible alternative to sprays for AMF control, we need to take into better account a range of factors that can affect trap performance (e.g. tree size, fruit load, tree cultivar, distance between traps) and substitute something (e.g. pesticide-treated spheres) for sticky spheres as traps. We report here on progress toward these ends.
Effect of Orchard Tree Size on Sphere Performance. The year 1999 was the concluding year of a 3-year study in 48 commercial orchard blocks on the influence of orchard tree size on performance of odor-baited sticky spheres in controlling AMF. Each year, traps were baited with the synthetic fruit odor attractant butyl hexanoate and placed 5 yards apart on perimeter trees of 8 blocks each of large (M.7), medium (M.26) and small (M.9) trees. Each block measured approximately 40 yards wide by 40 yards deep. An equal number of blocks that received 3 insecticide sprays to control AMF served as controls.
Results across the 3 years (1997-1999) showed that numbers of AMF captured per perimeter trap were about equal across blocks of all tree sizes. As judged by captures of AMF on unbaited spheres positioned near the center of each block (for purposes of monitoring penetration of immigrating AMF) and by percentage of sampled fruit injured by AMF, traps surrounding blocks of small trees were more effective in controlling AMF (relative to control obtained by insecticide sprays in comparison blocks) than were traps surrounding blocks of large trees. In fact, each year injury to fruit was slightly less in trapped than sprayed blocks of small trees but greater in trapped than sprayed blocks of large trees.
These findings indicate that baited spheres for controlling AMF should perform very well in high density blocks of M.9 trees but may not perform so well in blocks of low-density M.7 trees, with blocks of medium-density M.26 trees intermediate in performance expectations.
Effect of Fruit Load and Cultivar on Sphere Performance. Graduate student Juan Rull (of our lab) has been investigating effect of crop size and tree cultivar on ability of baited sticky red spheres to capture AMF. In 1999 studies in commercial and unsprayed orchards, he found that as apples mature and become larger and redder as the growing season progresses, they become increasingly competitive with sticky red spheres for the attention of AMF. Also, the greater the fruit load (i.e. number of apples per tree), the greater the degree of competition with sticky spheres. Together, these results suggest that more than one sticky sphere per baited tree may be needed to overcome visual competition from natural fruit. Fortunately, the amount of attractive odor emitted by fruit of even a highly attractive cultivar (e.g. Jersey Mac, Gala, Red Delicious) does not compete with the large amount of attractive synthetic fruit odor (butyl hexanoate) released from a single polyethylene vial hung in association with a sticky sphere. These combined findings suggest that control of AMF by traps placed on perimeter apple trees may be achieved best by grouping several baited spheres onto the same perimeter tree and then allowing several successive perimeter trees to go unbaited before again grouping several baited spheres on another perimeter tree. We will be evaluating this approach this coming summer.
Performance of Pesticide-Treated Spheres. From 1997-1999, we compared wooden pesticide-treated spheres and biodegradable pesticide-treated spheres with sticky-coated spheres for ability to control AMF in blocks of 49 trees per treatment in each of 8 commercial orchards. Each perimeter tree of each block received a baited sphere. A 4th block in each orchard received 3 summer insecticide sprays but no spheres for AMF control. The pesticide-treated spheres (PTS) received a coating of 70% latex paint, 20% sucrose to stimulate AMF feeding, and 10% Provado (yielding 2% a.i. imidacloprid). To replenish sucrose lost during rainfall, wooden PTS were capped with a disc comprised of wax and hardened sucrose that seeped onto the sphere surface, whereas sugar/flour PTS received sucrose that seeped from the interior of spheres onto the surface.
Results showed that across the 3 years, percent fruit injury from AMF averaged 4.2% in blocks having wooden PTS, 1.4% in blocks having sugar/flour PTS, 1.3% in blocks having sticky spheres and 0.9% in blocks receiving 3 insecticide sprays. Versions of PTS used in 1999 performed better than versions used in 1997 and 1998. Even so, caps of sugar atop wooden PTS required replacement twice during 1999 to ensure a sufficient amount of sugar on the sphere surface, and the majority of sugar/flour PTS in 1999 was eaten in part or whole by rodents, requiring replacement once or twice by new spheres.
In 1999, we also evaluated performance of Actara (thiamethoxam) as a potential substitute for Provado (imidacloprid) as insecticide on the sphere surface. Actara showed excellent kill of AMF alighting on wooden PTS under low to moderate rainfall conditions, but lost residual activity faster than Provado under high rainfall. Provado thus remains the best and most durable insecticide yet tested for combining with latex paint to coat the surface of PTS.
Future Plans on AMF. This spring, we plan intensive studies to improve the durability of top caps of sucrose for wooden PTS and to find an effective deterrent that will prevent rodents from eating sugar/flour PTS. We plan to evaluate our best candidates in commercial orchards this summer.
As a final note, this past November the Dean of the Business School of Western Illinois University formed a new company "Fruit Sphere, Incorporated" that will be manufacturing sugar/flour PTS for widespread testing in apple, cherry, walnut and blueberry plantings in eastern, central and western states in 2000 to control various species of fruit flies.
Pest mites are completely controlled by predatory mites on apple trees that receive no insecticide or fungicide. Some commonly used orchard pesticides kill or otherwise harm predatory mites, leading to pest mite outbreaks and need for frequent miticide application. In Massachusetts, the predatory mite Amblyseius fallacis is present in 90% of commercial orchards but it does not usually build to substantial numbers until mid-July or later, too late for early- and mid-season biocontrol of pest mites. Hence, in cooperation with Jan Nyrop of the Geneva lab of Cornell University, we embarked on a program of seeding third-level blocks with the predatory mite Typhlodromus pyri. This predator can provide effective pest mite biocontrol during early and mid season, provided certain harmful pesticides (e.g. pyrethroid and carbamate insecticides and EBDC fungicides) are not used. Until 1995, when we seeded it in some second-level IPM blocks, it was present in less than 10% of Massachusetts orchards.
In May of 1997, each of the third-level IPM blocks in commercial orchards received 100 blossom clusters containing T. pyri predatory mites. The clusters were sent to us by Jan Nyrop. All 100 clusters were fastened to the centermost tree of each 49-tree third-level block. No T. pyri were released in the first-level blocks. Every 2 weeks during July and August, we sampled leaves from the center tree, the 2 outermost trees in the center row and the center trees in the 2 outermost rows to determine degree of establishment and rate of spread of T. pyri in each third-level block. Comparable samples were taken from each first-level block. In all, nearly 13,000 leaves were sampled in 1997, more than 17,000 were sampled in 1998, and more than 17,000 in 1999. All samples were sent to Jan Nyrop for counting of numbers of pest and predatory mites in each sample. Identification of predatory mites to species requires highly specialized expertise not currently available at UMass.
Results on establishment and spread of T. pyri for all 3 years (1997, 1998 and 1999) show good establishment of T. pyri in 1997 on the trees on which they were released, and this establishment was maintained at about the same level during 1998 and 1999. There was very little spread of T. pyri in 1997 to the most distant trees up and down the row in which they were released, some up and down row spread (especially in blocks of small trees) by 1998, and excellent up and down row spread in blocks of all tree sizes by 1999. There was no spread whatsoever of T. pyri in 1997 to the most distant trees across row from which they were released, very slight across-row spread in 1998 (and only in blocks of small trees), and considerable across-row spread in 1999 (especially in blocks of small trees). T. pyri were essentially absent in 1997 and 1998 from blocks in which they were not released but were detectable in several such blocks (albeit in very low numbers) by 1999, indicating some spread of T. pyri by 1999 beyond the confines of blocks in which they were released.
Data on presence of A. fallacis mite predators (taken from 1998 and 1999) show somewhat lesser abundance of A. fallacis in blocks where T. pyri were released than where T. pyri were not released, with no detectable influence of tree size or location of sample site within blocks on abundance of A. fallacis.
Data on abundance of pest European red mites (taken from 1998 and 1999) show a powerful effect of T. pyri in suppressing pest mites in 1999 in blocks of all tree sizes in which T. pyri were released. The suppressing effect was not detectable in 1998. In 1999, it was greatest on trees on which T. pyri had been released and was least on the most distant trees across rows. Also, in 1999 it was comparatively greatest in blocks of large trees.
In sum, this 3-year study of the rate and spread of T. pyri among trees in blocks of different tree sizes shows that by the third year after release T. pyri can spread effectively as far as 3 trees away up and down row and 3 trees away across rows, with spread fastest and greatest in blocks of small tree size. Also, by the third year after release, T. pyri is able to very effectively suppress pest mites in parts of blocks where it has become firmly established.
In Massachusetts, leafminers have been a consistent foliar pest of commercial apple plantings since the late 1970s. Though present in at least low numbers in all orchards, some farms consistently experience above-threshold LM infestation, requiring chemical treatment. Over the past five years, LM infestation in some orchards has been highly pronounced, as LM have begun to exhibit spotty, unpredictable, explosive population growth.
To make matters more complex, the Massachusetts LM population actually consists of a combination of two major species: apple blotch leafminer (ABLM) and spotted tentiform leafminer (STLM). Until about a decade ago, ABLM was the dominant species present in commercial orchards in Massachusetts, while STLM was found predominantly in commercial orchards to the west and north, and infesting unsprayed or abandoned trees in southern New England. In the past several years, many orchards have experienced a distinct and rapid shift in LM species composition, with exotic STLM apparently displacing native ABLM.
In 1999, we undertook a major statewide research effort toward understanding the dynamics of shifts in LM species composition. The intent of this study was to determine whether trends in increasing LM population densities followed shifts in LM species composition and to investigate possible mechanisms for the apparent species shifts. Secondly, we aimed at determining the impact of mixed or unknown LM species compositions on the efficacy of current monitoring and management tools. In 28 eight-acre blocks, we tracked the population density and species composition of LM through all major population phases, from emergence of first-generation adults (from overwintered pupae) through development of third-generation pupae (and subsequent leaf drop). All told, we sampled over 30,000 leaves for evidence of LM infestation and identified nearly 8,000 LM pupae and 3,000 LM parasitoids.
Captures of LM adults on red sticky trunk traps were extremely high in 1999, averaging ~270 LM per trap (ranging from 1.3 to 1,372.0 LM per trap). Triggered by these unprecedented trap captures, most growers chose to apply an insecticide against first- or second-generation mines; the sprays (particularly Provado) were remarkably effective against even the highest LM population densities. With well-timed and effective chemical treatments, the average surviving first-generation mine density was reduced to 1.5 mines per 100 leaves. From these survivors, the statewide population grew 6-fold through the second generation and 28-fold through the third generation, yielding a late-season density of 42 mines per 100 leaves-well below a damaging level. Despite the overall efficacy of early-season LM treatments, orchards dominated by STLM experienced greater first-generation LM survival, followed by greater numbers of both second- and third-generation mines. This greater level of first-generation survival of STLM is certainly logical, as orchards dominated by STLM were generally subject to greater populations of first-generation egglaying adults, yielding higher levels of surviving mines in the face of chemical treatments. However, as the 1999 season progressed, the relative abundance of STLM increased markedly (compared with ABLM), with populations of STLM apparently holding the potential for much more explosive growth, particularly from the second to the third generation.
The relative impact of two major LM parasitoids (Sympiesis marylandensis and Pholetesor ornigis, both wasps) strongly affects the LM population growth potential in Massachusetts orchards. In samples taken in 1999 in unmanaged orchards (all dominated by STLM), mine density decreased by 60% from first to third generation (31.7 mines per 100 leaves to 12.7 mines per 100 leaves), solely due to the high levels of activity of LM parasitoids in untreated trees. In commercial orchards, parasitism rates averaged 35% in samples of first-generation mines, 30% in second-generation mines, and 14% in third-generation mines. S. marylandensis was (by far) the most commonly occurring parasitoid, though a few sampled orchards yielded 80-90% dominance by P. ornigis. Although both wasps are capable of offering effective biocontrol of LM in the absence of chemical sprays, data from 1999 samples suggest that P. ornigis may be a more reliable parasitoid of STLM, likely due to a greater synchrony between parasitoid and LM generations. However, the greatest season-long levels of parasitism were observed in orchards harboring both parasitoids (neither parasitoid accounting for more than 80% of parasitism).
Statewide data from this project suggest strongly that Massachusetts apple orchards are indeed undergoing a shift from ABLM to STLM. Additionally, it appears that this shift is more pronounced in commercial orchards that have moved away from use of some traditional management tools (pyrethroids, Vydate, Lannate) in favor of softer materials (Provado, Agri-Mek, Spintor). These data suggest that a shift in species composition (and associated management problems) may be a phase that all commercial orchards will eventually have to endure as a step toward biological control of LM. With this shift, monitoring and management strategies may require revision to accommodate mixed and changing LM species compositions.
Although the Food Quality Protection Act of 1996 requires that the EPA review all active ingredients currently registered, the spotlight continues to focus on the organophosphate (OP) class of compounds. These materials, the majority of which are insecticides, are labeled for a wide variety of uses including agricultural, veterinary, residential and structural. EPA must first consider all potential routes of exposure in assessing aggregate risk to human health posed by these compounds on an individual basis. Cumulative assessment of the OP's as a group will be conducted at a later date.
To date, only 2 (azinphosmethyl and methyl parathion) of the 5 active ingredients most commonly used in commercial tree fruit production have completed the EPA's 6-step initial review process culminating in risk management recommendations. The balance (chlorpyrifos, dimethoate, and phosmet) is currently under active review. Discussions of two materials with only limited usage in tree fruits (diazinon and malathion) have only recently been initiated. The following is a summary EPA's findings and actions as of February 21, 2000:
Azinphosmethyl - The initial review of azinphosmethyl (Guthion, Sniper) was completed on August 2, 1999. As registered at that time, EPA concluded that azinphosmethyl posed an unacceptable dietary risk to children ages 1 to 6, risks of concern to agricultural workers and unacceptable ecological risks. To mitigate occupational and environmental concerns, the registrants volunteered to amend their labels by agreeing to delete the use of azinphosmethyl on cotton in Louisiana and east of the Mississippi River, sugarcane, ornamentals (except for nursery stock), Christmas trees, shade trees and forest trees.
The majority of label amendments affecting tree fruit production was made prior to the 1999 growing season as the registrants were aware of EPA's concerns prior to the final decision and acted accordingly. Additional changes for the upcoming season include a reduction in total amount of product allowed per acre per season from 12 lbs. to 9 lbs, a variable PHI dependent on late season application rates and a prohibition on application by fixed wing aircraft.
Methyl parathion - The revised risk assessment for methyl parathion (Penncap-M) was also made public in early August 1999. Although not widely used in the Northeast, methyl parathion has historically been applied to approximately 20% of the apple acreage and nearly 50% of the peach acreage in the U.S. EPA indicated their primary concern was acute dietary risk to children, a portion of the population specifically addressed by the FQPA.
In order to reduce the risk to this sensitive sub-population, EPA accepted the registrant's voluntary cancellation of all children's food uses including fruit (apples, peaches, pears, grapes, nectarines, cherries and plums), carrots, succulent peas, succulent beans and tomatoes effective December 31, 1999. Additional food uses have been cancelled as well as non-food uses such as ornamentals, nursery stock, grasses grown for seed and mosquito control.
Phosmet - Phosmet (Imidan) has reached a critical point in the review process. EPA's revised risk assessment was released and a technical briefing was held in Pasco, WA on February 10. This event officially began the 60-day public comment period for submitting risk mitigation proposals. The revised risk assessment indicated that acute dietary risk was not an issue as phosmet accounted for an average of only 5% of the "risk cup" for all sub-groups. EPA also indicated that exposure to handlers (mixer/loader/applicators) could be satisfactorily managed with increased personal protective equipment (PPE) and engineering controls such as closed loading systems and enclosed cabs.
However, EPA did voice concern for post-application workers who may contact residues after applications have been made. Current information indicates that, depending on the rate used, acceptable margins of exposure may not be met until 37 - 52 days after application. Re-entry intervals of this magnitude would virtually eliminate phosmet as a pest management option for many crops. The registrant and other meeting participants raised objections to some of the assumptions EPA used to compile the worker exposure assessment and presented information as to how the assessment could be further refined during the risk mitigation phase.
Occupational exposure is regulated under FIFRA (Federal Insecticide, Fungicide and Rodenticide Act), not FQPA. As such, EPA is obligated to consider the benefits of a particular material when assessing its risk. Attendees reiterated to the EPA panel the importance of phosmet in existing IPM programs, its relatively low acute toxicity, its low impact on many beneficial species, the lack of viable alternative pest management options and the uncertain effects of potential replacement products on the crop ecosystems for consideration in determining the REI. EPA should release their risk management recommendations by late May to early June.
Dimethoate - Dimethoate (Cygon) is currently in Phase 5 of the review process since the release of the revised risk assessment and technical briefing in mid December. As with methyl parathion, this material has not been an important tool for producers in the Northeast but according to USDA surveys, dimethoate is applied to 35% of the total U.S. apple acreage and is labeled for approximately 40 other food crops.
Despite its widespread usage, EPA is not concerned with aggregate risk from diet or drinking water. Worker exposure and ecological issues seem to be their main concern. The registrants, U.S. Apple Association, and EPA are currently discussing methods to reduce this risk in tree fruits by utilizing increased PPE, decreasing the maximum seasonal rates per acre and lengthening re-entry intervals for high-contact activities such as hand thinning, summer pruning and harvesting.
Chlorpyrifos - Chlorpyrifos (Lorsban) is somewhat in limbo in Phase 4 of the review process. The public comment period following the preliminary risk assessment ended December 27 and EPA is currently reviewing any new information that may have been put forth in preparation for releasing their revised risk assessment. No date has yet been set for the technical briefing but it should occur sometime in late March. After that event, there will be another 60-day public comment period and then EPA will have up to 60 additional days to compile the final risk mitigation proposal.
Diazinon and malathion - Both of these materials have just begun the review process. EPA has shared their first-tier risk assessments with the registrants for error comments only. Preliminary risk assessments have yet to be released for public review.
It is clear that EPA is making progress in implementing the legislation passed in August 1996. Initial review of the OPs should be completed by the third quarter of this year. The focus will then shift to the next two priority groups of pesticides; carbamates (Benlate, Topsin, Sevin, Lannate, Vydate) and potential carcinogens (Captan, mancozeb, Polyram)-many of which are prominently used in commercial fruit production.
To date, with a few notable exceptions, dietary issues have played a secondary role to worker exposure concerns in assessing the OPs. This may change in the future as EPA looks at cumulative risks associated with materials that have similar modes of action. In September 1999, the Scientific Advisory Panel agreed with EPA's intention to group certain carbamate pesticides with the OPs when assessing cumulative risk. Placing more materials in the same "risk cup" could substantially reduce the number of labeled uses that could be retained and still satisfy the requirements of the FQPA. Cumulative risk assessments have not been a part of the registration process in the past and EPA has been working on the protocols needed to carry out this aspect of the legislation concurrent with their initial reviews of individual compounds.
It is uncertain how the FQPA will ultimately affect commercial agriculture but it will undoubtedly change our pesticide usage patterns. With the increased restriction on uses of older compounds, we must strive to keep up with the introduction of new and innovative pest management options. Change is the only constant.
For those growers interested in following FQPA developments closely, the URL for the EPA web site giving the status of the OP review process is www.epa.gov/pesticides/op/status.htm.
Most local peach growers by now are likely aware that plum pox virus, or sharka, was positively identified (for the first time in North America) last fall in Adams County, Pennsylvania. The affected area was quarantined, and an extensive survey was rapidly out carried before leaf fall in numerous stone fruit plantings in the mid-Atlantic region. Thus far, no plum pox has been found outside this limited area in Adams County, nor has the ultimate source of inoculum yet been identified. More extensive surveying will be done during the upcoming growing season over a much broader area, possibly including New England stone fruits.
Plum pox virus affects all stone fruits and is a serious stone fruit disease in Europe. In addition to the unsightly fruit symptoms described below, infected trees suffer a loss of vigor and productivity, and frequently die if exposed to significant additional stress. There is no cure, and no variety of stone fruit is known to be truly resistant; scientists at USDA/ARS are working on introducing transgenic resistance, but this work is a long way from completion. Thus, the fact that the disease has been positively identified in North America is being taken very seriously.
Symptoms of the disease vary somewhat across cultivar, age, nutrient status, temperature, and plant part infected. Leaves may show light green discoloration bordering the leaf vein, or yellow to light green rings. Fruit may develop lightly pigmented yellow rings or line patterns from several rings running together. Fruit may become deformed in shape and develop brown dead areas. In some varieties symptoms may also show up on blossoms. Visible symptoms may not appear during the first year that the plant is infected.
The virus is transmitted by aphids, including the green peach aphid. Transmission is nonpersistent; once the aphid has picked up the virus in its stylets, the virus remains infectious and can be transmitted by the aphid for a period of only a few minutes to an hour. The virus does not increase in the aphid and does not circulate in the aphid's body. Virus that has been picked up from an infected plant by an aphid will be ejected the next time the aphid performs a 'test probe'; if the test probe site is in healthy tissue, the site will become infected. But aphids feeding on an infected cell can only transmit the virus to the next cell on which they feed.
Pennsylvania and several adjacent states have applied for a Section 18 Special Local Needs usage of Provado to control aphids on peaches. At present, Massachusetts is not requesting this usage, since we do not have any reason to assume that plum pox virus is present (we hope it isn't, but we do need to be vigilant), and since peach aphids in this region seem to be well controlled by currently registered materials.
All stone fruit growers should be alert for symptoms of the virus, and should contact an Extension specialist if any suspicious symptoms are found. It is entirely in the interest of every individual grower and of the growing community at large to identify and report any possible sources of plum pox inoculum. In addition to visibly infected trees, nearby nonsymptomatic stone fruit trees would also need to be tested so that all infected tissue would be removed. If funding is available, random surveys and ELISA testing may be conducted in local peach orchards by APHIS and/or the Massachusetts Department of Food and Agriculture.
An excellent flyer describing the current situation with plum pox, with photos of symptoms on fruit and leaves, has been produced by workers at Pennsylvania State University and is available online at [http:sharka.cas.psu.edu] or as a free publication (Code UL204) from Pennsylvania State University, 112 Agricultural Administration Building, University Park, PA 16802-2602.
1999 Activity. For the 6th consecutive year in Massachusetts, TPB captures on monitoring traps and TPB injuries to fruit in apple orchards were below levels experienced during the first half of the decade. The same pattern was true in 1999 in other New England states. Such a long run of below-average TPB infestations could be due to (1) a coinciding long run of unfavorable weather conditions for building of TPB adults during autumn or survival of adults during winter; (2) consistently poor weather for TPB activity during spring; (3) declining availability of favored flowering plants (especially legumes) for building of TPB during summer and autumn (coinciding with decline in dairy farming); or (4) an increasing degree of region-wide biocontrol of TPB by parasitoids. Any one or a combination of these factors could have been operating in our favor over the past several years, but increasingly it appears that parasitoids may be the major factor (see below).
New Findings. Alan Eaton and cooperators in New Hampshire surveyed levels of the parasitoid Peristenus digoneutis in several New England states in 1999 and have found this parasitoid (introduced into the region about 1990) to be taking a major toll on TPB, especially on some of its favored hosts like alfalfa. If this sort of biocontrol continues, TPB could indeed be a relatively minor concern in future apple pest management. In contrast, no such parasitoids have yet been found in Nova Scotia, and growers there are experiencing increasing damage from TPB.
Actara was tested against TPB in 1999 field trials by Dick Straub in the Hudson Valley. A single application at pink gave excellent TPB control (much better than Guthion) but a single application at petal fall gave poor control (probably because the great majority of TPB injury had already occurred). Actara is the first new insecticide in a long time to show very good TPB control and also be comparatively safe on beneficials. The manufacturer of Avaunt indicates that it too is very effective in controlling TPB, but we haven't seen any data on this as yet.
1999 Activity. GPM is an insect that feeds on apple leaves and developing blossoms. Until 1999, it was not widely recognized as being a commonly seen insect in commercial apple orchards in New England. Because fewer orchards have received pre-bloom treatments targeting TPB in recent years, there is greater opportunity for other sorts of insects to step forward and be noticed. Chris Maier of Connecticut reported GPM first entered that state in 1997 and that all New England states experienced noticeable populations of GPM in 1999. Moths lay eggs near unopened flower buds on apple trees early in spring. Larvae hatch in a short time (about half-inch stage of bud development), reach about one-half inch long, and have a red stripe running lengthwise down their pale green abdomen. Larvae web young leaves together and feed inside a "tube" created by the woven leaves. Larvae also venture forth and eat holes in flower petals at pink and eat pollen from inside unopened blossoms. They complete development just before bloom, before the appearance of developing fruitlets. Such fast spread of GPM through New England is surprising. Fortunately, it appears that populations would have to be very large indeed to more than moderately thin developing blossoms by feeding. However, the quality of spur leaves is important to adequate fruit set, and populations of GPM that do become very large may interfere with adequate fruit set.
New Findings. The above information reflects what is known about GPM in New England to date. There are no other new findings.
1999 Activity. Although populations of EAS were at or slightly below average in Massachusetts in 1999, they were high to extremely high in some other areas this year, such as parts of Connecticut, Maine, and Quebec. This insect, introduced into mid-Atlantic states about 60 years ago, continues to spread methodically throughout the Northeast, recently reaching central Ontario.
New Findings. The only new development of note is that parasitoids of EAS larvae from Poland were introduced into Quebec about 5 years ago and have now become firmly established on abandoned apple trees. Future plans call for Quebec researchers to introduce these parasitoids into New England, where they might help suppress EAS on unmanaged trees.
1999 Activity. Fruit damage from PC in 1999 in Massachusetts was the lowest in recent memory (averaging 0.2% across 48 monitored blocks in commercial orchards). This was only about one-eighth the level of PC injury experienced in the same monitored blocks in 1997 and 1998. The same was true in other mid and southern parts of New England. The main reason: very few wild apple trees bore fruit during 1998. Thus, there was scarcity of resources available for production of new PC adults during the summer of 1998. With so few adults going into overwintering quarters, one could predict that PC populations in 1999 would be low. We may not be this fortunate again for some years hence.
New Findings. In a preceding section of this March Message, we reported on our 1999 findings on PC responses to odor and visual cues associated with traps and on progress in developing a trap for PC.
In 1999, we made collections of PC adults and larvae from wild plums and apples in Massachusetts, apples in Wisconsin, and peaches and blueberries in New Jersey, and sent them to cooperating geneticist David Hawthorne of the University of Maryland to determine their degree of genetic relatedness. Results of analyses are not all in yet, but one very interesting finding of a different sort has emerged. We allowed larvae from infested apples in Massachusetts and infested blueberries in New Jersey to develop into pupae and adults, and then in August we offered these newly emerged adults apples to see if they would lay eggs. As expected, none of the Massachusetts adults did so. All ate from the apples and then entered overwintering diapause. But the adults from New Jersey pummeled the apples with eggs, and have since produced 5 generations of adults in 7 months. This means that the multi-generation southern strain of PC has made it as far north as central New Jersey. If we think we have a problem with PC in Massachusetts infesting fruit in May and June, imagine having to cope with at least one more generation of PC that attacks and lays eggs in fruit in August and September. We should consider ourselves lucky in having PCs that have only one damaging generation per year.
The new insecticides Actara and Avaunt were tested against PC in 1999 in field trials by New England Fruit Consultants in Massachusetts, Dick Straub and Peter Jentsch in the Hudson Valley, Harvey Reissig in Geneva, and John Wise and Larry Gut in Michigan. Combined findings indicate that Actara was just about as effective as Guthion or Imidan against PC and that Avaunt was only slightly less effective than Actara. This is very good news. If field trials in 2000 show the same sort of results, then potentially these will be two new insecticides, both comparatively safe on beneficials, that could substitute effectively for organophosphates for controlling PC. The major downside would be that new types of insecticides usually are very costly. This attaches even greater importance to the need for an effective monitoring trap for PCs that will allow targeting of treatments only when and where needed.
The new insecticide Surround (kaolin clay) was evaluated in 1999 for PC control in Prokopy's small orchard in Conway and by Henry Hogmire in West Virginia. It showed promise in both locales, providing 80% control of PC in 2 applications in Conway (compared with 90% control of PC by one application of Imidan). We plan to do more testing of Surround in 2000.
In New York, Harvey Reissig compared 2 different approaches to PC control in 1999: (1) a border-row spray approach that involved application of Asana at petal fall to the 2 rows of apple trees nearest the orchard border, followed by use of a degree day (DD) model (developed in New York) to time the second and last PC spray (this model relies on accumulation of heat units to indicate that residual activity of a pesticide ought to extend through 325 DD to ensure adequate late-season protection against PC), and (2) two whole-block sprays of Guthion. Results showed averages of 1.4% and 0.7% injury to fruit in the border-row and whole-block treatments, respectively, compared with 6.8% injury to untreated check trees. These findings support earlier results in Massachusetts and subsequent results in Quebec that border-row sprays against PC, if well-timed, can provide effective PC control without continual spraying of entire blocks, at least in some circumstances. An approach relying only on border-row sprays would not be effective against European apple sawfly, however.
1999 Activity. Like plum curculio and for the same principal reason, AMF populations and injury were unusually low in 1999 in Massachusetts. Captures on monitoring traps were way down from 1998 levels, and did not reach detectable numbers until mid-August, when some rainfall finally arrived. Average AMF injury to fruit in commercial orchards was only 0.1% at harvest (0.5% injury is the 10-year average). The same was true elsewhere in central and southern New England.
New Findings. In a preceding section of the March Message, we reported on our 1999 findings of experiments using odor-baited traps for controlling AMF.
In 1999, AMF populations were so low that few reliable data could be obtained in New England on field performance of new insecticides against AMF. New England Fruit Consultants used attractive odor (butyl hexanoate) to lure AMF into experimental plots of otherwise unmanaged trees treated with Avaunt or Spintor. Four summer applications of Avaunt and 7 summer applications of Spintor gave control equal to that of 4 summer applications of Guthion.
Thus, there is promise that one or more new insecticides may be an effective substitute for organophosphates against AMF. However, the high cost of using these materials at doses great enough to provide effective control could be a drawback. Moreover, in the case of Avaunt, tests conducted in our own laboratory in 1999 showed that it is ineffective as a contact poison against AMF and must be ingested to be effective. Other recent tests we have conducted show that AMF entering commercial orchards from wild hosts in border areas have very little propensity to feed and may not readily ingest a toxic dose of Avaunt. Field trials of Avaunt conducted to date usually involve AMF that emerge beneath treated trees, are hungry for food, and could readily ingest a toxic dose. Results of such trials could be misleading and could suggest that Avaunt is more effective in controlling immigrating AMF (the vast majority of AMF in commercial orchards) than it really is. More research is necessary to sort this out.
In western New York, Harvey Reissig made 4 summer applications of several different materials against AMF and found Avaunt to be about as effective as Imidan and Lorsban in controlling AMF, whereas Actara and Spintor were less effective, though Spintor was effective in 8 applications. In Michigan, John Wise and Larry Gut found that 4 summer applications of Surround (kaolin clay) or Actara were just as effective as 4 summer applications of Guthion or Imidan in controlling AMF, whereas 4 summer applications of Avaunt or Spintor were ineffective.
1999 Activity. Normally, we consider SBs only as a pest of peaches. But in 1999 in Massachusetts, SBs appeared to be the culprit in causing nearly 10% injury to monitored apples in at least one commercial orchard. Injury was noticed first during August and appeared initially to look like egglaying stings of apple maggot. Toward harvest, damage on fruit began to look more like cork spot or bitter pit, with a tiny hole in the center of the blemish where SB mouthparts had been inserted. Damage was greatest in blocks where understory grass was tall during August and where baited spheres but no insecticides had been used to control apple maggot.
In 1999, reports began to appear of similar damage to apples in the Hudson Valley and in Washington. There also, SBs are the suspected culprits. In one monitored block in Washington, damage exceeded 50% of sampled fruit. For the future, we probably need to be much more mindful of SBs as summer pests not only of peaches but also of apples and other tree fruit.
New Findings. Observations in Washington State indicate that populations of SBs in orchards are greatest (a) where mullein (a favored host) is abundant near an orchard, (b) when dry weather causes SB hosts near orchards to dry up in mid-summer and result in SB immigration into orchards, and (c) on perimeter rows of trees nearest areas of SB buildup in orchard borders. Perhaps the most effective pesticide against SBs tested to date in Washington State is Surround (kaolin clay), applied to apple trees during August. Possibly Actara and Avaunt, which may be effective in controlling TPB, also might provide effective control of SBs, but we have seen no data on this as yet.
1999 Activity. Over the past 3 decades, moth pests of apples and other tree fruit have generally been of rather minor concern to Massachusetts growers. Populations of codling moth, oriental fruit moth, lesser appleworm and leafrollers have rarely flared to levels in commercial orchards that required a special treatment of insecticides. With advancement to higher levels of IPM that involve little or no insecticide application after mid-June and with development of resistance of some moth pests to organophosphates and carbamates, the situation may be changing. This is especially true for codling moth in western states and leafrollers in western New York and Ontario. For Massachusetts, the most imminent threat may be from oriental fruit moth (OFM).
OFM adults are at peak emergence around pink and may escape control if no pre-bloom insecticide is used. First-generation larvae bore into apple shoots, much as they do into peach terminals. Second and third-generation OFM larvae bore into fruit. Injury appears very similar to that caused by codling moth and lesser appleworm, with an OFM larva eating away fruit flesh near the surface and leaving a decayed area visible through the thin outer skin of fruit. Unlike lesser appleworm but like codling moth, OFM larvae bore toward the center of the fruit, leaving a tunnel in their wake. The only sure way to distinguish between OFM and codling moth larvae is to look for an anal comb on mature larvae. OFM larvae have one-codling moth larvae do not. The comb is a small, dark comb-like appendage at the very posterior end of a larva.
OFM has been building in some orchards in Massachusetts during 1998 and 1999, especially in orchards in the Berkshire hills and especially in blocks receiving very reduced pesticide use. In western New York and Ontario, some apple orchards are now experiencing flagging of terminal shoots, much in the same way that peach orchards suffer flagging of shoots from boring by first-generation OFM larvae. Assays conducted in 1999 in New York and Ontario show as much as 70% of OFM in some orchards are now potentially resistant to organophosphates and carbamates. Further south in New Jersey and West Virginia, OFM became a major-league problem on apples in 1999. According to Mark Brown of the USDA lab in West Virginia, the apparent major reason for OFM building there-in addition to possible resistance-could be substitution of the newer materials Confirm and Comply for organophosphates and carbamates. These newer materials are timed for use against other pests in such a way that there now exists a window of opportunity for OFM to sneak in and cause a lot of trouble. As pesticide use patterns in Massachusetts will soon begin to change in a way more dramatic than anything we have seen in the past 30-40 years, we will need to keep a careful eye on OFM and other moth pests.
New Findings. In the Hudson Valley, Dick Straub found in 1999 that Actara applied 3 times (petal fall and first and second cover) did an excellent job-as good as Guthion-in controlling early season OFM and other similar moths. But these sprays were not enough to stop late-season OFM and relatives, which caused high injury to apples. In Michigan, John Wise and Larry Gut found that Guthion applied 7 times beginning at petal fall provided 90% OFM control and that a similar program of Spintor or Avaunt sprays provided about 70% control. In North Carolina, Jim Walgenbach found that Avaunt did a better job than Imidan in controlling OFM on apples there. Finally, Henry Hogmire in West Virginia found that Surround (kaolin clay) was equally as effective as Imidan in 8 sprays in controlling OFM on peaches. Further tests in 2000 will help clarify possibilities for better controlling OFM, but it does appear that Surround, Avaunt and Spintor may offer hope as substitutes for organophosphates.
1999 Activity. Leafhoppers were not a noticeable problem in Massachusetts and other New England states in 1999. Widespread use of Sevin as a thinner coupled with widespread use of Provado against leafminers controlled first generation white apple and rose leafhoppers so effectively that orchards using these materials experienced little trouble from later-generation leafhoppers in August and September. Potato leafhoppers arrived, as usual, about mid-June-long after residual activity of Sevin and Provado had disappeared. But populations of these leafhoppers, which can be devastating to newly planted trees, seemed lower in 1999 than in recent years.
New Findings. The only notable new finding on leafhoppers in 1999 comes from a report by Doug Pfeiffer in Virginia on results of several experiments testing ability of leafhoppers to transmit Erwinia bacteria that cause fireblight. No species of leafhopper was found to vector Erwinia in the normal way in which a vector carries microorganisms in its mouth parts from one plant to another. Nor were white apple leafhoppers found in any way to be associated with the spread of Erwinia from one apple tree to the next, perhaps because their feeding sites are confined to mesophyll tissue of leaves, which is not the sort of tissue infected by Erwinia.
However, potato leafhoppers were found to be associated with the spread of Erwinia.
These leafhoppers feed in the vascular tissue (phloem) of leaves, especially young, vigorously growing shoot tip tissue, precisely the kind of tissue most vulnerable to infection by Erwinia. Potato leafhoppers begin to appear about the same time as the onset of shoot blight and are very active, moving much more frequently among trees than other leafhopper species. The wounds they create with their mouthparts seem to be well suited to permitting entry of Erwinia, possibly carried on the exterior of the mouthparts into the vascular tissue of leaves.
The take-home message from the Virginia studies is that if you have had a problem with fire blight, it may pay to keep a watchful eye on potato leafhoppers and time a pesticide in blighted blocks to coincide with first appearance of the leafhopper. Such a treatment could help reduce the spread of fire blight.
Results of 1999 insecticide trials against leafhoppers show the following. In a test by New England Fruit Consultants, Avaunt at petal fall did a very good job of controlling white apple leafhoppers (WAL) through harvest. In North Carolina, Jim Walgenbach found that in late-June treatments, Provado gave excellent control of WAL through harvest, but control by Spintor (if any) was completely lost by harvest. Finally, Henry Hogmire in West Virginia found that Actara at petal fall was almost as good as Provado at petal fall in controlling WAL for the next month, and that Surround in twice per month applications from petal fall through August gave outstanding WAL control.
1999 Activity. The explosion of leafminers in autumn of 1998 translated into massive adult emergence in the spring of 1999 in Massachusetts. Trunk trap captures were the highest yet recorded in Massachusetts (up to nearly 4000 adults on single trunk traps) and unprecedented egg densities were observed on flower clusters (100 or more eggs per cluster). Of 24 monitored blocks, 90% exceeded threshold levels of adults by pink. Nearly all growers applied Provado at petal fall, which gave excellent season-long control in most cases. Very high leafminer populations were commonplace also in Connecticut and Rhode Island, but leafminers seemed to be less of a widespread problem in northern New England in 1999.
New Findings. In a previous section of this March Message, we reported on our findings from a study of species composition of leafminers and associated parasitoids in more than 20 commercial orchards in Massachusetts in 1999. Our findings show that the leafminer situation in Massachusetts is undergoing a metamorphosis, with rapid changeover in some orchards from dominance by apple blotch leafminers (ABLM) to dominance by spotted tentiform leafminers (STLM)-a potentially more explosive species.
Visual traps stapled to tree trunks continue to be effective for monitoring first-generation ABLM adults but appear to be less effective for monitoring STLM, possibly because STLM adults seem to emerge a bit later in spring than ABLM adults and are less inclined to seek out tree trunks as heat sinks but more inclined to fly directly into the canopies, bypassing visual traps on tree trunks. Another factor that we found in 1999 tests to influence effectiveness of trunk traps is distribution of overwintered leaves on the orchard floor. Where bare ground predominates beneath tree canopies, most overwintered leaves are removed by wind to alleyways and orchard border areas. Leafminers emerging from these leaves were found to have much less chance of being captured by trunk traps (but just as great a chance of appearing in the canopies) as leafminers that emerged from overwintered leaves that remained beneath tree canopies.
Together, these findings suggest that traps placed within tree canopies (rather than on tree trunks) may be a better all-around indicator of adult leafminer populations across orchards of varying types. The problem of using sticky red visual traps hung horizontally (by far the most effective orientation within tree canopies) for this purpose is that captured adults are easily smashed by raindrops and soon become difficult to identify. Pheromone traps can be used but so far no one has been able to relate levels of trap captures to levels of subsequent mines. A way out of this dilemma is to count numbers of leafminer eggs on fruit cluster leaves. This is the most accurate approach for predicting future larval density and has been used in New York and Ontario for many years. However, it is time consuming and requires training in identification of eggs, which are difficult to detect if hatched. The most reliable of all sampling methods is to count sap-feeding mines. Here too, there is a shortcoming for pest management purposes. Sap-feeders may show up too late for optimum timing (petal fall) of some pesticides. In short, there is no single way of sampling for first-generation leafminers that is both simple and reliable under all conditions.
One question that arose repeatedly in 1999 involved optimum timing of post-bloom sprays against first-generation leafmines. The major concern was if Provado applied at petal fall would have enough residual activity to control larvae that hatched and entered leaves one or two weeks after petal fall. The answer appears to have been a resounding "yes"! Provado sprayed at petal fall did a great job of control in Massachusetts and Connecticut. Additional information on the residual activity of imidacloprid (=active ingredient of Provado) in leaves came from a 1999 study in Israel, where imidacloprid remained highly lethal to whiteflies arriving on tomato plants up to 15 days after application but toxicity declined quite rapidly after that. On the flip side, some orchards in both Massachusetts and Connecticut experienced somewhat less effective leafminer control using Provado applied 10 days or more after petal fall, probably because some larvae were already too advanced in development by then.
With respect to trials of existing and new insecticides against leafminers in 1999, new England Fruit Consultants as well as John Wise and Larry Gut in Michigan and Jim Walgenbach in North Carolina compared Provado with Spintor, Actara, or Avaunt and found that all four materials performed quite well, with Provado having a slight edge in effectiveness. Henry Hogmire of West Virginia reported that Surround applied every two weeks gave good, but not excellent, leafminer control. It appears that soon we will have a wide variety of materials to choose from for effective leafminer control-materials that are considerably safer on beneficials than materials like pyrethroids, Vydate, and Lannate that dominated leafminer control in the past.
1999 Activity. Spring weather in 1999 was very favorable for oil application against mites, and some orchards in Massachusetts that received double-oil treatment before bloom and no further mite control experienced no more than low to moderate European red mite (ERM) populations the remainder of the year. Orchards treated with Savey, Apollo or Agri-Mek also fared well in ERM control, despite very warm and dry conditions in June, July and August that were very conducive to ERM buildup.
The only mite problem of real note in 1999 was with two-spotted spider mites (TSM) which became troublesome in some Massachusetts orchards in July and August. TSM can reach large numbers on broadleaf plants on the orchard floor. When such plants undergo stress from drought (as they did in 1999), or are mowed, TSM are stimulated to leave the groundcover and seek more favorable conditions elsewhere. Hence, there were cases of TSM building in tree canopies during mid-summer. As expected, Pyramite did not perform well in rescue sprays against TSM. But in Rhode Island, Heather Faubert observed that Vendex did a fine job as a rescue material in mid-summer against TSM in at least two orchards.
New Findings. In a previous section of this March Message, we reported on findings of our third and final year of a study of the speed and pattern of spread of released Typhlodromus pyri predators in commercial orchards and the degree of mite biocontrol provided by such predators. If use of materials such as pyrethroids, Lannate, Vydate, Agri-Mek, and EBDC fungicides that adversely affect T. pyri can be avoided or minimized, then introduced T. pyri offer great hope of providing season-long mite control without need to resort to any pesticide other than pre-bloom oil sprays.
In 1999 in the Hudson Valley and western New York, a two-year study was completed of the comparative effect of Asana (a pyrethroid) vs. Guthion on ERM buildup. Each insecticide was applied six times beginning at petal fall and ending in July. In orchards experiencing a high carryover of ERM eggs from the previous fall, use of either material (but especially Asana) invited an ERM outbreak if no miticide beyond oil was used. However, when accompanied by Apollo or Agri-Mek in the presence of a moderate or low population of overwintering ERM eggs, neither material triggered an ERM outbreak. The bottom line from this work seems to be that even though Asana is deadly to mite predators, it can be used to control insect pests in orchards without undue risk of a mite outbreak as long as overwintering ERM eggs are comparatively low in number and use is in conjunction with an effective miticide.
In western New York, a 1999 trial comparing different application times of miticides against ERM showed that for tight cluster applications, Apollo plus oil gave better ERM control than Apollo alone but that the best control of all was by either Apollo or Savey at petal fall. In the Hudson Valley, a 1999 trial showed that Apollo as well as Savey applied once at second cover in early June gave excellent ERM and TSM control through early July, whereas Pyramite applied in early June failed to control TSM. In yet another 1999 trial in the Hudson Valley, the insecticide Avaunt appeared to significantly suppress both ERM and TSM. In a 1999 trial in West Virginia, Pyramite did a much better job than Savey in controlling ERM as a rescue material applied in late June. Neither was as effective as Apollo applied at first cover. Also in West Virginia, Surround applied every 2 weeks during the growing season did not control ERM and may have caused mites to flare by adversely affecting mite predators.
Finally, Dick Straub and Peter Jentsch in the Hudson Valley evaluated 5 different miticides as rescue materials against high populations of TSM during the summer of 1999. Vendex proved very effective (corroborating above-reported observations in Rhode Island). Somewhat less effective were Vydate and Agri-Mek. Pyramite was comparatively ineffective, and Carzol was downright useless, affording no TSM control whatsoever.
1999 Activity. Pear psylla (PP) populations were well below average in most of New England and New York in 1999. Dry weather from June through mid-August slowed proliferation of succulent tissue of watersprouts and leaf terminals, thereby depriving PP of resources that favor rapid buildup.
New Findings. The principal new findings of substance on PP came from 1999 trials of conventional and reduced-risk insecticides conducted by Dick Straub in the Hudson Valley. In dual applications (10 and 21 days after petal fall), M-Pede and Pyramite gave excellent PP control, followed by Agri-Mek and Provado, with Neemix also performing fairly well but not as strongly as the other materials. For Pyramite and Agri-Mek (though not for Provado) dual applications gave better PP control than a single treatment at 10 days after petal fall.
For 2000, the monthly newsletters; weekly Healthy Fruit messages; the March Message; the Peach, Pear and Plum Guide; and the 2000-2001 New England Pest Management Guide will be available for a subscription of $45. Subscriptions may be ordered by sending a check for $45 made out to the University of Massachusetts to Wesley Autio, Department of Plant and Soil Sciences, Bowditch Hall, University of Massachusetts, Amherst, MA 01003. Single copies of the March Message are also available for $5, and may be useful to out-of-state growers as an alternative to the entire Massachusetts subscription. Copies of the following publications may be ordered individually from the UMass Extension Bulletin Center:
The 2000-2001 New England Apple Pest Management Guide will be mailed to all who subscribe to the $45 package of information. The 2000-2001 NEAPMG was edited by Glen Koehler, Alan Eaton, Lorraine Los, Lorraine Berkett, Wes Autio, Jim Dill, Bill Lord, and Elena Garcia.
The 1999-2000 Peach, Pear and Plum Guide includes updated pest biologies and control methods. The Peach, Pear and Plum Guide is edited by the UMass Tree Fruit Team.
Tree fruit management guides should only be used during the growing season(s) for which they were written. Information obtained from old guides may be outdated and may result in illegal pesticide application, or growers may miss new information about phytotoxicity or effectiveness. We highly recommend that growers discard old pest management guides in favor of the updated versions.
Two fact sheets are available on biological control of mites and leafminers on apples.
2000-2001 New England Apple Pest Management Guide $15.00
1999-2000 Peach, Pear and Plum Guide $7.50
Opportunities for Increased Use of Biological Control in Massachusetts ID Code: EXPF 0900 0718 $7.00
Biological Control Fact Sheets:
Apple Blotch Leafminer ID Code: IPMA 000L 594A $2.95Spider Mites in Apples ID Code: IPMA 000L 595A $2.95
The costs above include production, handling and mailing expenses. Checks should be made out to the University of Massachusetts and sent together with your order to the Bulletin Center, Draper Hall, University of Massachusetts, Amherst, MA 01003. Please use the ID code (if provided) to specify the publication you are ordering.
Fruit Notes of New England is a quarterly journal published by the UMass Plant and Soil Sciences Department and UMass Extension. It contains important new research findings on fruit growing in Massachusetts. The subscription price is $10 per year ($12 US funds for foreign subscriptions), and checks should be made out to the University of Massachusetts and sent to Wesley Autio, Department of Plant and Soil Sciences, Bowditch Hall, University of Massachusetts, Amherst, MA 01003.
Healthy Fruit is published weekly from early April through early August, and contains timely information regarding pest management, such as insect and disease phenologies and management options and crop management strategies, such as thinning and fruit maturity. It is provided to all package subscribers via e-mail or first-class mail, or can be faxed for an additional $20 fee. Subscription requests, e-mail distribution requests, and fax copy requests should be sent to Wes Autio [autio@pssci.umass.edu].
2000 Tree Fruit Production Guide. Penn State University. Price $13.00. Make checks payable to Penn State and send with your name, address and the title of the publication you are requesting to Publications Distribution Center, College of Agricultural Sciences, Penn State University, 112 Ag Administration Building, University Park, PA 16802. Penn State's distribution center can also take telephone order (for credit card purchases) at (814) 865-4700.
Updated New York Fact Sheets Among others, the Tree Fruit Fact Sheets set includes:
Pear Psylla
Plum Curculio
Obliquebanded Leafroller
Apple Maggot Fly
European Red Mite
Rosy Apple Aphid
White Apple Leafhopper
Woolly Apple Aphid
Beneficial Insects
Brown Rot
Powdery Mildew
Apple Scab
European Apple Sawfly
Comstock Mealybug
Codling Moth
Green Fruitworm
Peachtree Borer
Spotted Tentiform Leafminer
Predatory Mites
San Jose Scale
Dogwood Borer
Oriental Fruit Moth
Redbanded Leafroller
Fire Blight
Cedar Apple Rust
Sooty Blotch and Flyspeck
Tarnished Plant Bug
Phytophagous Mirid Bugs
The New York Fact Sheet series features excellent photographs, and a set of 30 can be purchased for $28.35. Individual sheets are also available for $2.00 each. These can be ordered from Media Services Resource Center-GP, 7 Research Park, Cornell University, Ithaca, NY 14850.
Pest Management Fact Sheets. Cooperative Extension Service, University of New Hampshire, Durham, NH 03824. Free of charge. Fact sheets are available on:
Tarnished Plant Bug
Redbanded Leafroller
Plum Curculio
Two Spotted Spider Mite
Scale Insects
Apple Scab
Codling Moth
Apple Maggot Fly
European Red Mite
Aphids
Fire Blight
Common Tree Fruit Pests, published in 1994. A comprehensive guide to identification and control of more than 50 arthropod pests of tree fruits. Written by entomologist Angus Howitt of Michgan State University. Contains many excellent color pictures and straightforward information on most pests encountered in the field. Available in hardcover ($37.50) or laminated ($30.00) from: Bulletin Office-TFP, Michigan State University, 10B Agricultural Hall, East Lansing, MI 48824-1034. The publication number is NCR-63 (Common Tree Fruit Pests). Checks should be made out to Michigan State University.
Mid-Atlantic Orchard Monitoring Guide. Published in 1995 by the Northeast Regional Agricultural Engineering Service, under the guidance of West Virginia University and with input from fruit researchers throughout the Mid-Atlantic region. Contains thorough and current information on pest and disease biology, monitoring and treatment, as well as nutrition, irrigation and fruit evaluation. Many color photographs. Available for $75.00 from Northeast Regional Agricultural Engineering Service, Cooperative Extension, 152 Riley-Robb Hall, Ithaca, NY 14853-5701. Checks should be made payable to NRAES.
A variety of pheromone and visual traps is commercially available to growers as pest monitoring aids. We have had considerable experience with the following traps as part of our IPM research and extension efforts over the past years.
Leafminers - Pheromone traps for spotted tentiform leafminer (STLM) adults have been used in Massachusetts, but they are of uncertain effectiveness in attracting apple blotch leafminers (ABLM), which is also present in most commercial orchards in Massachusetts.
Codling Moth (CM), Obliquebanded Leafroller (OBLR), Oriental Fruit Moth (OFM), Redbanded Leafroller (RBLR), Variegated Leafroller (VLR), Lesser Appleworm (LAW), Sparganothis Fruitworm - Although traps have been used in the Massachusetts IPM program, these pests are not usually much of a problem and so we have rarely used trap-capture data for management decisions. As part of our ongoing extension efforts, we plan to continue to monitor these pests closely, as these pests may have the potential to develop resistance to commonly used organophosphate compounds. Monitoring for these pests will be more important with a very low spray schedule, as shown by recent increases in Oriental fruit moth activity under reduced spray schedules.
Lesser Peachtree Borer, Peachtree Borer, Dogwood Borer - Pheromone traps are available for determining appearance and abundance of adults.
Tufted Apple Bud Moth, Green Fruit Worm - Generally these pests have not been a problem in Massachusetts orchards and we have not used pheromone traps for them in our IPM program. Green fruitworm was a major problem in a few western Massachusetts orchards in the early 1980's but numbers have declined in subsequent years.
Tarnished Plant Bug (TPB) - We continue to experience good results with the sticky white rectangle traps for TPB. These traps should be set out at silver tip (no later), with pesticide application need and timing based on cumulative captures from silver tip to tight cluster or pink.
Leafminers - Sticky red visual traps, stapled to tree trunks at silver tip, continue to prove useful in indicating adult emergence and in predicting need for treatment pre-bloom or at petal fall in orchards dominated by ABLM. Orchards with mixed or unknown LM species composition may gain more reliable data from horizontal LM traps placed in the tree canopies.
European Apple Sawfly (EAS) - EAS adults are highly attracted to sticky white rectangle traps that mimic apple blossoms. Traps should be placed at pink; the need for pesticide application is based on cumulative captures from pink to petal fall.
Apple Maggot Fly (AMF) - Sticky red spheres that mimic ripe Delicious apples are an excellent aid in monitoring AMF abundance. They are especially helpful in June and July for determining first arrival of flies in early-variety blocks and in August and September for determining arrival of late season flies immigrating into blocks of Delicious and other late season varieties. Traps should be positioned in late June for early-developing and mid-season varieties and in early July for late-developing varieties. Sticky red spheres baited with synthetic apple volatiles developed in New York are 2-4 times more effective in capturing AMF than unbaited sticky spheres alone. Traps should be cleaned of insects and debris regularly, preferably once every 2 weeks, as capturing effectiveness will decrease with the accumulation of dead insects. Several variations of sticky red spheres, including lightweight plastic molded traps, are available from the IPM products division of Gempler's and Great Lakes IPM.
Pear Psylla - Sticky yellow traps can be placed 1-2 m from the ground in the south quadrant of the tree to monitor adult activity in spring.
Pear Thrips - Sticky yellow traps should be set three feet high. We use a tomato stake and a metal shelf bracket to mount the trap in the correct position. Traps should be checked at least weekly from ground thaw until fruit bloom. Current recommendations call for a minimum of four traps per ten acre block. Monitoring for thrips populations in nearby overwintering areas (e.g. sugar bushes) can help to determine the potential for thrips immigration.
Tangletrap (Bird Tanglefoot) is a clear, odorless, non-drying adhesive that is used to coat the reusable red sphere traps. Tree Tanglefoot is also a non-drying adhesive, but it should not be used with the red sphere traps since it is not clear or odorless.
Scare-Eye bird control balloons have given good to excellent results in reducing bird injury to Cortlands and other susceptible varieties. One balloon is effective over a radius of approximately 20 yards.
Pheromone traps, synthetic apple volatiles, visual traps, bird repelling balloons, Tangletrap, and magnification equipment for use in sampling are available from:
Gempler's
211 Blue Mounds Road
P.O. Box 270
Mt. Horeb, WI 53572-0270
(800) 382-8473 (Orders)
(800) 332-6744 (Customer Service)
Great Lakes IPM
10220 Church Road
Vestaburg, MI 48891
(517) 268-5693 or
(517) 268-5911
Many pest management supplies are also available from:
OESCO, Inc. (Orchard Equipment)
Rt. 116
Conway, MA 01341
(413) 369-4335
In addition to the weekly monitoring and other information provided through University of Massachusetts Extension IPM, growers are strongly urged to monitor their own orchards, or hire private consultants to do so.
The UMass Tree Fruit Advisor is available on the World Wide Web, at http://www.umass.edu/fruitadvisor/. This site includes Tree Fruit Team contact information; current issues of Fruit Notes, the March Message and Healthy Fruit; and links to other resources, such as Orchard Radar, chemical labels, the NEAPMG, and nutrient management information. Questions about the system should be referred to Wes Autio [autio@pssci.umass.edu].
Two private consulting businesses will continue to offer IPM consulting, scouting, and other services in Massachusetts in 2000. Their addresses are:
New England Fruit Consultants (NEFCON)
56 Taylor Hill Road
Montague, MA 01351
(413) 367-9578
(413) 367-0313 (FAX)
Polaris Orchard Management
364 Wilson Hill Road
Colrain, MA 01340
(413) 624-5104
|
|
|
|