Insect and Mite Management

Ron Prokopy, University of Massachusetts
Alan Eaton, University of NewHampshire, Alan.Eaton@unh.edu

New Products

Acramite (bifenazate) 50% Water soluble packets. 0.75 - 1.0 lb./A. For European red mite and two spotted spider mite. An organosilicate spray adjuvant is recommended, like Silwet L-77, Silgard 309 or Kinetic. Apply in a minimum of 50 gals. water per acre. Maximum of 1 spray per year. Restricted entry interval 12 hours. Preharvest interval 7 days.

Actara (thiamethoxam) 25% water dispersible granules. Rates vary. For (prebloom) aphids, leafminers, mullein bug : 4.5 oz./A. For leafhoppers postbloom : 2.0 - 2.75 oz./A. For Eur. apple sawfly, plum curculio, leafminers and aphids postbloom : 4.5 - 5.5 oz./A. Make no more than one prebloom application. Do not exceed 8 oz./A. for the season. Allow a minimum of 10 days between applications. Actara has rapid local systemic activity, and is relatively safe to beneficial arthropods. It is quite toxic to bees. Use a minimum of 50 gals. of water per acre. Thiamethoxam is closely related to imidacloprid (Provado). Restricted entry interval 12 hours. Preharvest interval 35 days if rate is over 2.75 oz./A. and 14 days if rate is 2.75 oz./A. or less.

Avaunt (indoxacarb): 30% WG, 5-6 ozs./acre. Registered for control of tarnished plant bug, plum curculio, codling moth, oriental fruit moth, lesser appleworm, leafrollers, apple maggot, and leafhoppers. Maximum of 4 applications per year at no more than 24 ozs. total annual per acre. Make no more than 3 applications prior to hand thinning. No hand thinning after 4th application. For best results, apply in 50-150 gal. water per acre and never more than 200 gal. water per acre. Performs well against tarnished plant bug, plum curculio, some leafrollers, and leafhoppers. Performance against apple maggot has been variable. Avaunt represents a new class of compounds (oxadiazines) and is more toxic when ingested by insects than by contact alone. Toxic effects are not immediate but gradual, sometimes requiring 3 or more days. It is not systemic and does not protect new growth. Does not redistribute readily on foliar surfaces once sprayed. Residual activity lasts 7-14 days depending on conditions. Safe on most beneficials. Restricted entry interval 12 hours. Preharvest interval 28 days.

Aza-Direct (azadirachtin) 1.2% EC For beetles and weevils: 12.5 - 42 oz./A. True bugs (like TPB), leafhoppers, aphids, leafrollers, flies, mites : 11.5 - 42oz./A. Azadirachtin may be acceptable for organic growers. Repellant and antifeedant action on moths and caterpillars, toxic and growth suppressant on moths, caterpillars, aphids, leafhoppers. Maximum effectiveness requires 2 - 3 applications, at intervals of 7 - 10 days. Restricted entry interval 4 hours. Preharvest interval 0 days.

Distance (pyriproxyfen) 0.86 lbs/gal L, 6 to 8 fl. ozs./100 gals. for aphid suppression on non-bearing trees; 8 to 12 fl.ozs./100 gals. for San Jose scale and spotted tentiform leafminer on non-bearing trees. The active ingredient (same as Esteem) is an insect growth regulator, so it does not affect adult insects. Restricted entry interval 12 hours. Preharvest interval: can only be used on non-bearing trees.

Intrepid (methoxyfenozide): 80 WSP, 3-6 ozs./acre. Registered for control of codling moth, lesser appleworm, leafrollers and leafminers. Effective also against oriental fruit moth. Maximum of 20 ozs. total material per acre per year. Performs best in conjunction with an adjuvant to maximize deposition, redistribution, and weatherability. Belongs to diacylhydrazine class of insecticides and has novel mode of action that mimics action of molting hormones of moth larvae. Must be ingested by larvae to be effective. Works best against internal feeders when application is just prior to egg hatch. To avoid resistance, do not use against more than 3 consecutive generations of a pest. Very safe on beneficials. Restricted entry interval 4 hours. Preharvest interval 14 days.

Valero (cinnamaldehyde) 30%L, 1-9 gals/acre. Registered for control of aphids and spider mites. Label recommends a phytotoxicity check before treating, to ensure that treatment is safe for your varieties. Experience with products that have this ingredient (but used in greenhouses) suggests that it loses effectiveness several weeks after being opened. Cinnamaldehyde is a component of cinnamon, the ground inner bark of certain tropical trees in the laurel family. Spray water should have a pH of 3.5 to 7.5, or product degradation may result. Pests must be directly contacted by spray; residual activity 1 day or less. Restricted entry interval 4 hours. Preharvest interval 0 days.

Changes in Labels of Other Registered Compounds

Guthion: The "old" label for Guthion is still in effect. The proposed changes to the label have still not been agreed upon. EPA's "proposed final" changes may be revised (public comments being reviewed now) but currently are as follows: The product may be used for 4 more years. Maximum amount per year is 3.5 lbs active ingredient per acre. Restricted entry interval is 14 days. Preharvest interval is 30 days for PYO orchards, 14 days for others if no more than 1 lb. active ingredient was used per acre. Closed transfer systems are required for mixing and loading. Applicators must use maximum personal protective equipment, or be in enclosed cabs.

Imidan: EPA's "proposed final" changes may be revised (EPA is reviewing comments now) but now are as follows. For product manufactured after June 30, 2002: The product may be used for 5 more years. "Backyard" uses are being discontinued. Restricted entry interval is now extended to 3 days. Preharvest interval remains unchanged at 7 days. Existing products may be used with the existing labels.

Lorsban: Effective as of December 31, 2000, the use of Lorsban 4E and Lorsban 50W on apples is restricted to pre-bloom applications only. EPA recently amended that by approving supplementary labels for both products (3/15/01) that allow application of these materials to the lower trunk only (for borers) after bloom. Check with your in-state specialists to see if your state has approved that use for the product. There are several restrictions on these supplemental labels, which are aimed at avoiding post-bloom spray contact with foliage or fruit.

New Timing Recommendation for Dogwood Borer Control

(Lorraine Los, University of Connecticut)

Lorsban treatments applied as a trunk spray during pre-bloom (half-inch green through pink) or at petal-fall are effective for control of dogwood borer in apple burrknots. This is based on current research by Dave Kain, Dick Straub and Art Agnello from Cornell University. Both the Lorsban 4E and Lorsban 50W formulations are available for use pre-bloom. Note: There may be some concern of phytotoxicity if the Lorsban 4E contacts flower buds during pink, especially if done during hot weather. Therefore, the 4E formulation probably should not be used beyond the tight cluster stage. However, these borer sprays are dilute applications, applied with a hand-gun and directed to the lower trunk area. There should be little (if any) direct contact with the tree canopy. No phytotoxicity was observed in the Cornell research when these directed sprays were used. According to the 2002 Cornell Recommendations the rates to use are 1.5 qts./100 gal. for Lorsban 4EC or 1.5 lb./100 gal. for Lorsban 50W. Specific use directions are on the supplemental label which must be in the possession of the user at the time of application. Although the supplemental label indicates use during the post-bloom period, it is legal to use pre-bloom in Connecticut. Growers in other states should check with their Cooperative Extension Fruit Specialists to confirm if these treatments can be used in your state.

Herbicides and Groundcover Management

Jon Clements, University of Massachusetts, clements@umext.umass.edu

Changes in herbicides from the 2000-2001 New England Apple Pest Management Guide include the proliferation of "Roundup-like" products containing glyphosate, and the introduction of several new pre-emergent herbicides for non-bearing orchards. You are reminded that weed-free strips under young orchards will do much to improve young tree growth and early yields.

Here are a few of the specific herbicide changes and/or additions for 2002:

Pre-emergence herbicides

Isoxaben (Gallery* 75DF, *Trademark of Dow AgroSciences) – Selective, pre-emergent control of broadleaf weeds in NON-BEARING (non-crop) fruit trees only. Apply in late fall or early spring. In newly planted trees, allow soil to settle before application. Tank mix with post-emergence herbicide and/or Prowl to control emerged weeds and grasses. Restricted-entry interval (REI) 12 hours.

Snapshot* 2.5TG (*Trademark of Dow AgroSciences, a premix of 2% trifluralin and 0.5% isoxaben) – For NON-BEARING apples, stone fruit. Provides broader spectrum of control than either chemical alone. (i.e. both broadleaf weeds and annual grasses.) Not effective on emerged weeds. Apply late fall or spring immediately after cultivation. Restricted-entry interval (REI) 12 hours.

Post-emergence herbicides

2-4-D – Several brand names, but use only those with a label for orchards. A selective herbicide effective on broadleaf weeds. BEWARE of drift, as grapes, flowers, and vegetables are extremely sensitive to 2, 4-D.

Clethodim (Select® 2EC, Valent Biosciences) – A post-emergence selective (grass-only) herbicide, similar to Poast, Fusilade, etc. Somewhat effective on quackgrass, however, addition of ammonium sulfate or a crop-oil concentrate at 1% or minimum 1 pint/acre suggested. Follow all label precautions to avoid crop injury. For NON-BEARING apples, pears, stone fruit. (i.e., first leaf trees) only. Restricted-entry interval (REI) 24 hours.

Glyphosate (Roundup Ultra Max, Touchdown, Glyphomax 4SC) – As the Monsanto/Roundup patent has expired, several manufacturers are producing these glyphosate-based non-selective, systemic herbicides. Two (or three) applications of glyphosate during the growing season may give effective, season-long control of most weeds (including grasses) in the tree row, although a spring tank mix with a pre-emergent herbicide may be useful. Avoid use of glyphosate later in the summer. Shield trunks of young trees (1st leaf) from spray. Do not use on peaches. Hard water can reduce the effectiveness of glyphosate sprays – use of a water conditioner or ammonium sulfate is recommended.

Glufosinate-ammonium (Rely) – A non-selective, contact herbicide that gives faster results than glyphosate but somewhat slower than gramoxone. It is, however, more suppressive (particularly on broadleaf weeds) than gramoxone. Excellent control of suckers on established trees.