Scaffolds 99 index

RELEASE THE HOUNDS

(Jan Nyrop jpn2@nysaes.cornell.eduand Dave Kain dpk1@nysaes.cornell.edu, Entomology, Geneva)

The mite predator Typhlodromus pyri can give biological control of European red mite when the predator is conserved in apple orchards. Experiments have shown that, once established in an orchard, this mite can completely eliminate the need for miticides. While T. pyri is endemic throughout much of western New York, it can take as many as three years in specific orchard blocks for predator numbers to increase to the point where biological control is realized. Moving T. pyri from blocks where they are abundant to sites where more predators are desired (seeding) can speed this process.

Phytoseiid mite larva, nymph and adult (l. to r.)

Instances will occur when it is necessary to use pesticides that are toxic to T. pyri to control other orchard pests. To combat the resulting disruptions of mite biological control caused by these pesticide applications, it has been suggested that orchardists establish sites to be used as mite "nurseries". These sites would not be treated with pesticides harmful to T. pyri and would be used as sources of predators that could be moved to orchards where predators are scarce; the practice of transferring them could therefore become an important ingredient of any integrated mite control program.

The first method of moving T. pyri from one orchard block to another is to place wood pruned from a source orchard in winter or early spring into a recipient orchard. Because T. pyri overwinter as adult females, prunings harbor predators, although numbers in each section of pruning are highly variable. We suggest placing all the prunings from one tree into another tree. It is probably not effective to simply spread the prunings beneath recipient trees. Pruned wood need not be placed in the recipient trees immediately after pruning, but should be placed there before or just when trees begin to produce green tissue the following spring.

The second method consists of transferring flower clusters from a source orchard to a recipient site. T. pyri move into flower clusters at Tight Cluster and remain there through bloom, probably to feed on apple pollen. As many as 2 to 3 predators can be found in each flower cluster and surrounding leaves. To transfer predators in this manner, at least 20 flower clusters (and associated wood and leaves) should be placed in each recipient tree. The flower clusters are easily attached with paper clips, staples, or twist ties. Flower clusters may be stored for several days in a cooler before being affixed to receiver trees.

The third method of transferring T. pyri consists of collecting leaves during the summer from trees where T. pyri are abundant, and placing them into recipient trees. Leaves are easily affixed to the target sites using staples. The number of leaves to use depends on the density of T. pyri in the source orchard. As a guide, at least 50 predators should be released in each target tree.

The fourth method of transferring T. pyri is perhaps the easiest and does not carry the risks of also moving unwanted pests that the three prior methods have. Artificial overwintering sites for T. pyri can be created by glueing burlap to the inside of tree wrap. These composite bands, approximately 12 to 16 inches in length, are then placed on source trees in early to mid-September by stapling them around the tree bole and/or large scaffold branches. In early December, these bands should be collected, tightly rolled with a rubber band used to hold them so, and placed in a sealed plastic bag with a bit (i.e., a "puff") of wet cotton. The bag should be placed in an insulated storage container, which in turn should be placed in a cold, though protected, environment that will buffer large temperature fluctuations. Ideally, temperatures should be maintained right at the freezing point. The following spring, the burlap bands should be placed around recipient trees at around the Half-Inch Green bud growth stage. While the number of predators that overwinter in bands is variable, as many as 400 predators can be transferred in each band. We suggest placing a single band on each recipient tree if the bands were collected from trees that harbored moderate to high numbers of T. pyri (1-2 per leaf) the prior fall, and two bands in each tree otherwise.

While T. pyri overwinter throughout the tree, there are apparently many predators that overwinter on large branches or the trunk itself and that move into the canopy as foliage appears. Use of nurseries in which T. pyri are cultivated, and transfer of branches harboring T. pyri from these nurseries to target sites, should allow biological mite control to be more persistent on a farm-wide scale. The second season after seeding T. pyri and using nondisruptive pesticides in our IPM Demo blocks in western N.Y., predator numbers were at levels of more than 1/leaf by the end of August, and true biological control (that is, no oil or acaricides) of ERM was realized in all blocks by the third year.

Phytoseiid mites feeding on European red mites

Unlike petroleum oils applied early in the growing season, oils applied during the summer can have an adverse effect on phytoseiid numbers. However, this effect is apparently only significant when high volumes of oil suspension are applied. Our opinion is that oil applied using conventional airblast sprayers will have only a minimal negative effect on phytoseiid numbers. As such, summer oil applications can be recommended as a way to help manage European red mite numbers if predator numbers are insufficient for biological control. For a more detailed discussion of the ins and outs of establishing predator mites, refer to IPM Pub. #215, "Achieving biological control of European red mite in northeast apples: An implementation guide for growers", by D. Breth, J. Nyrop, and J. Kovach" (1998), from which much of this information was adapted.

HONEY BEES, RENTAL FEES, AND POLLINATION CONTRACTS

(Nick Calderone nwc4@cornell.edu, Entomology, Ithaca)

Making a decent living in farming demands close attention to costs, and it is only reasonable that a grower will try to find the best price for each of the inputs that go into his or her crop production system. When it comes to honey bees, however, growers usually don't look inside the hives to see what they are buying, and even if they did, most wouldn't know a good hive from a bad hive. Most growers understand the need for quality hives, but don't have the expertise to determine that quality. The result is that the emphasis is usually on unit cost rather than the cost/benefit ratio, and the goal is generally to pay as little as possible. Downward pressure on prices does not always produce the highest quality. Beekeepers, faced with low rental fees, may have little choice but to split colonies so that they have more units to rent. Nobody really comes out a winner.

A lot has changed in the past few years. Most notable is a new system put in place by Cherryfield Foods, Inc., the largest producer of lowbush blueberries in Maine. Cherryfield Foods is a progressive, successful and rapidly growing concern. As new management practices have increased plant and flower density, they have also increased the need for honey bees. One of the reasons for Cherryfield's success is that it has a farm manager who recognized the role honey bees play in determining yield and quality. Cherryfield has adopted a very reasonable policy to ensure a sustainable supply of high quality honey bees for pollination--they pay well! That's right, they aren't shopping the bargain basements, they pay top dollar for the top hives. They take care of the beekeeper, and they take care of the bees. It's all spelled out in a simple contract. The basic points in the contracts are:

* Specify arrival/departure dates and location several months in advance (with some flexibility built in to account for variation in weather conditions);

* A Cherryfield representative meets the beekeeper at delivery and sees to it that the bees are placed in the right location;

* Cherryfield provides electric fences to protect against bear damage;

* Cherryfield shares the cost of bear damage to hives;

* Cherryfield inspects about 3% of the hives in a random manner -- beekeepers are encouraged to attend;

* A minimum of 6-7 deep frames of brood and 8 deep frames of bees is defined as a base unit.

* Payment is based as follows:

- 0-3 frames brood = $0.00

- 4-5 frames brood and bees = $20% less than base rate

- 4-5 frames brood with a full box of bees = base rate

- 6-7 frames of brood and bees = base rate

- 8-10 frames brood and bees = 20% above base rate

* The base rate for 1998 is $50.00;

* Hives placed in areas that are hard to reach receive a $3.00 bonus

* Cherryfield helps with situations in which trucks become stuck;

* Cherryfield is understanding of legitimate problems that arise, like truck breakdowns; all they ask is that the beekeeper stay in communication with the farm.

* Payment is 1/3 upon delivery, 1/3 within 2 weeks of departure, and 1/3 within the next 30 days.

* If Cherryfield fails to pay on time, they will add 3/4% interest per month to the balance.

That's pretty much all there is. Cherryfield is happy with the results they have gotten, and so are the beekeepers. The contract is based on the carrot and the stick. Beekeepers that provide top quality colonies and make a good living; those that don't, either get up to speed or are weeded out to make room for those who will. Cherryfield ensures a ready supply of the very best colonies because they make it economically possible for the beekeeper to provide them. You can hold the beekeeper to a high standard and, if you pay a reasonable rate, they will be more than happy to do whatever it takes to keep your account. Ask your local county extension educator for sample contracts.