Pesticide Applicator Needed

The Fruit Team has a new federal grant that involves a need for someone experienced in applying pesticides in orchards. Beginning in May 2001 over a four year period, we hope to hire someone at a rate of $30 per hour to make pesticide applications in each of six Massachusetts orchards seven times during the growing season in each year. We estimate 200 hours per year of work. We will provide the sprayer, tractor, and truck for hauling. If interested, please contact Ron Prokopy (413-545-1057) or Arthur Tuttle (413-545-3748).

Calendar

• February 26-28 New England Farmer's Direct Marketing Conference, Manchester, NH (413-529-9232)
• March 1 Dwarf Apple Pruning Clinic, Sunnycrest Orchard, Sterling MA (413-323-4208)
• March 2, 9, 23, 30 RUP Applicator License Exam, Waltham MA (617-626-1786)
• March 6 Dwarf Apple Pruning Clinic, UMass HRC, Belchertown MA (413-323-4208)
• March 15 RUP Applicator License Exam, Springfield MA (617-626-1786)
• March 20 Dwarf Apple Pruning Clinic, Ed Sylvia's, Dighton MA (413-323-4208)
• March 22 Sprayer Calibration Clinic, UMass HRC, Belchertown MA (413-323-4208)

RUP (Restricted Use Pesticide) Applicator License Exams

For those of you that need to get or renew your Restricted Use Pesticide (RUP) applicator license(s), here are the exam dates and location for the month of March. You must submit an application to the Massachusetts Department of Food and Agriculture (617-626-1786, www.massdfa.org/pesticides/) at least one week before the exam date. For more information, call MDFA or visit the UMass Pesticide Education Program web site, www.umass.edu/umext/programs/agro/pesticide_education/. The Program also has training sessions scheduled for Waltham and Hadley-see the web site or call MDFA for more details. Exam Dates:

• March 15, 20001: Springfield Technical Community College, One Armory Square, Springfield, MA 01105. (application must be received by MDFA by March 8)
• March 2, 9, 23, 30: UMass Extension Center, 240 Beaver St., Waltham, MA 02154 (applications must be received by MDFA one week before exam date)

USDA Farm Service Agency Taking (Some) Applications

Apparently your local Farm Services Agency office has begun accepting applications for the 'Special Apple Loan Assistance Program,' however, the anticipated 'Apple Market Loss Program' application process is on indefinite hold. Sign-up was to have begun January 18, then was postponed to February 1, however, according to FSA they are still awaiting for sign-up details on the program from USDA. In fact, the US Apple Association (www.usapple.org) sent a letter to new Agriculture Secretary Ann Veneman urging her immediate "assistance in providing our nation's beleaguered apple growers with the $1000 million in market loss assistance promised to them by Congress." FSA also says sign-up details for the 'Apple Quality Loss Program for 1999/2000 Crop' are not available yet either. Although it's very likely application packages for both these delayed programs will be received by FSA offices in the near future, and funding is not in jeopardy ,it might pay to contact your congressional representatives to convey your urgency in receiving the assistance.

Leaf Analysis Results

We've observed that leaf analysis results from many Massachusetts orchards often show a magnesium deficiency. Magnesium is an important mineral nutrient-right up with nitrogen, potassium, calcium, and boron for healthy tree growth and quality fruit production.
Growers need to pay particular attention to magnesium deficiency and take immediate steps to correct it. Why? According to retired Cornell University Extension Specialist Dr. Warren Stiles (in his publication 'Orchard Mineral Nutrition,' see below) magnesium deficiency can result in:

• weak, thin, and brittle shoots and spurs
• accentuated fruit drop
• premature leaf drop, resulting in blind wood development and weaker flower buds
• and restricted root growth

Dr. Stiles also explains that magnesium deficiency is more likely to occur:

• during period of drought
• with heavy crop loads
• in rapidly growing young trees
• and when potassium is high

His recommendation is to not rely solely on foliar application of magnesium-although Epsom salts help where obvious deficiencies exist-but to supply the orchard's primary magnesium demand with ground application(s). Where pH is low (< 6, need to do a soil test) dolomitic lime is a good source, although the magnesium content can vary. Other options include Sul-Po-Mag, kieserite (hydrated magnesium sulfate), ground-applied Epsom salts, and a custom fertilizer blend with magnesium added.

Dr. Stiles publication Orchard Nutrition Mangement (142IB219 $4.25) should be in every grower's library-it is available from Cornell University Media Services (607-255-2080, resctr@cornell.edu). Another excellent publication on orchard nutrition is Fertilizing Fruit Crops (E-852) by Michigan State's Eric Hanson-call Jon Clements (413-323-4208) if you'd like a copy.

Apple Pruning Approaches to Maximize Orchard Performance

By Jeremy Compton, Rutgers North Jersey Tree Fruit Technician and Win Cowgill, Area Fruit Agent
(note: Jon Clements "comments" follow paragraphs in italics)

Orchard productivity and development are direct functions of sunlight. Sunlight management is the key to high annual yields and a profitable orchard. Annual pruning is a necessary practice that maintains the profitability of an orchard. Knowing not only what must be cut out but also what should be left in and how the tree will respond is the science behind pruning. The productivity of an orchard can be affected for the next three years by cuts made this season! It is critical for growers to know what will result from management decisions made now, and understand what technique will maximize profits in the long run. "Remember that pruning always reduces yield. We sacrifice fruit yield but gain fruit quality by annual pruning. There is truly a fine line between over- and under-pruning-think of it as the yield vs. quality challenge. You, as the orchard manager are best able to judge where this line lies, hence making the pruning decisions that optimize both yield and quality."

The main objective of orchard management through pruning is to maximize sunlight interception by the orchard and the distribution of that light within the trees canopy to maximize fruit quality for this season and fruit bud initiation for next seasons crop. Proper light interception and distribution is key for growing high quality fruit. Correct pruning and tree manipulation techniques allow for this to occur on an annual basis. Growers should also keep in mind other important factors that justify the need for pruning, such as the maintenance of proper tree height, structure, and appropriate balance between vegetative growth and fruit which allows for annual cropping of high quality fruit with better color and increased sugars. Penetration of spray materials and natural reduction of pest pressure are other factors that are directly affected by pruning. "In reality, sunlight interception is a function of tree spacing and height-i.e., the orchard system. Pruning affects light penetration and distribution within the tree canopy. Research has shown that the canopy light environment must be no lower than 30% of the available sunlight to produce high quality fruit and spurs for successive cropping."

In most cases, we prefer to discuss pruning in a manner that stresses the complimentary process of tree manipulation (training) in the same text. Intensifying planting densities also dictates the need for pruning to be dependent on manipulation. But for the sake of time we will just discuss important rules of pruning as they apply to all orchard densities.

Although pruning is an overall dwarfing process, it is locally invigorating, stimulating vegetative growth at the site of the cut. On a non-bearing tree, this type of stimuli causes the tree to remain in the vegetative mode, which delays cropping. For this reason, pruning young non-bearing trees should be avoided unless correcting major structural defects. Tree training and minimal corrective pruning of tree structure in the non-bearing years are critical to the overall performance of an orchard throughout its life. Branch manipulation (training) plays the major role on tree structure and precocity (how quickly the orchard bears a crop) in the non-bearing years of an orchard. Only minor pruning should be done until the tree bears a crop for a year. After the tree has produced a crop, then it is time to begin an annual pruning regiment. Since no major pruning is to be done prior to this time, the tree may need a lot of attention (depending on variety), but in a controlled manner over a period of years. An excessive amount of pruning at any single time will cause an overstimulation of vegetative growth and a loss of balance within the tree. Excessive pruning can also cause sunburn to the fruit and wood of sensitive varieties such as Gala and Golden Delicious. "Clearly, in young orchards, tree training should be emphasized over pruning. First, minimal pruning allows trees to begin bearing sooner. Second, emphasis on limb positioning/bending, and central-leader management will produce a tree that has good structure and will be much easier to live with down the road. And third, focusing on training vs. pruning will result in trees that are far 'calmer' and will likely require less pruning during the orchard's life."

The central leader is the trees natural regulator. Tree performance and structure depends heavily on the manipulation of the leader. Cutting into the central leader can cause a loss of control with that tree or delay cropping on non-bearing trees. Heading cuts on a central leader should be done at planting when conditions warrant its use, and should be the last option used to induce branching on established trees. If more branching is desired, other techniques such as notching, bending or the use of plant growth regulators may provide a better alternative for inducing branching on the leader. Never cut into the central leader without knowing what responses the tree will express. "It's almost a given that nursery trees will require heading at planting-the exception being large, well-feathered trees planted hi-density. I frequently see un-headed trees during their first and second leaf that are not developing good structure, are not growing vigorously, and will never realize their potential. Please head your trees (usually at waist height) shortly after planting."

There are two types of pruning cuts made, heading and renewal cuts. A heading cut is when a cut is made into a branch or the leader, cutting back to a weaker shoot along that branch or leader. Heading cuts stimulate excessive growth at the site of the cut, and will stiffen the wood that has been headed. Juvenile (1 year old) wood will respond much more prolifically to such a cut as opposed to mature wood. Heading cuts should be avoided unless the intent is to cause one of these two responses to occur. Unnecessary heading cuts into an established limb or scaffolds juvenile wood will cause an excessive amount of flush growth, that will shade out the tree and be counterproductive to good tree management techniques. If tree growth suppression and the maintenance of a compact tree are the only desired effects from a heading cut, always cut an established limb or scaffold back into a mature, bearing side shoot or limb. When making a heading cut never cut a limb back to blind wood (deadhead). The result will be tip dieback and wood rots will occur. Renewal cuts, on the other hand, are cuts made at the point of branch origin. Most renewal cuts are intended to remove a branch that is no longer desirable because of vigor concerns or excessive crowding. Renewal cuts, on established trees, are always into mature wood and will not spark the vegetative regrowth that a heading cut will. "Renewal-I prefer to think of them as 'thinning'-cuts are far preferable to heading cuts in maintaining calm trees. Avoid heading cuts like the plague-use only where you need to promote tree vigor."

Any scaffold or limb that is half the size or larger in diameter to the main leader should be removed. A branch of this size will choke out the leader, not allowing the tree to reach optimal fruiting capacity. By leaving a limb of such girth, the constriction problem compounds every year and eventually the limb will be larger and more dominant than the leader itself. The bending of such a limb to the horizontal will slow a limbs growth, but in an instance where the limb is already out of proportion to the main leader, growth will not cease completely, and the limb will continue to hinder the trees growth and performance. In a crowded mature orchard, this technique can be used in a reverse manner. By leaving such a dominant scaffold in place, future tree growth will be retarded (as discussed above) and the limb will aid in controlling tree size. "Pretty self-explanatory. Get rid of those problem branches early-don't let them ever compete with more positive, fruitful branches. Another good rule-of-thumb is to remove any upright branch or potential scaffold limb exceeding a 45 degree angle from horizontal."

Spur pruning is a good way to rejuvenate trees that are heavy spur bearers such as Red Delicious and Empire. A tree will produce its highest quality fruit on spurs that are 2-5 years old. Any spur that is older than 5 yrs yields reduced quality fruit. That spur is no longer efficient and should be removed. The age of a spur can be determined by its size. "Concentrate on removing old, non-vigorous spurs that jut upright or hang down from the fruit bearing limb."

The proper balance between fruit and vegetative growth is another important relationship. An imbalance between the two can result in inferior quality fruit and biannual bearing. No two systems or cultivars will respond in the same manner to the above presented techniques, but understanding these procedures, and the response they induce will help reduce the gamble of making an improper decision. Growers need to be conscious of details that relate specifically to their cultural systems, and proper ways of managing them. "I like to keep plenty of pencil-size diameter one-year-old wood for development of new fruit buds the coming season. Pruning should be thought of as a continual renewal process, where older fruiting wood is replaced by younger fruiting wood with the potential for producing higher quality fruit."

There are many more techniques and tree responses that need to be understood when managing an orchard. Each orchard system provides new and unique techniques to the growing process. Sometimes, less is more, and understanding what can be manipulated is just as important as knowing what needs to be removed. An orchards optimal performance will never be achieved if this relationship is not understood and maintained.