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April, 14 2008 Volume 17 No. 4 Update on Pest Management and Crop Development


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Upcoming Events

Current DD accumulations



(Geneva 1/1-4/14:



(Geneva 1/1-4/14/2007):



(Geneva "Normal"):



(Geneva 1/1-4/21 Predicted):



(Highland 3/1-4/14/08):




Coming Events: Ranges
(Normal +/- Std Dev):

Green apple aphids present



Green fruitworm peak catch



Obliquebanded leafroller larvae active



Pear thrips in pear buds



Redbanded leafroller 1st catch



Rosy apple aphid nymphs present



Spotted tentiform leafminer 1st catch



McIntosh at green tip







4/21 (Predicted)

Apple (McIntosh):

Silver tip

1/2-inch green

Apple (Delicious):

Silver tip

Green tip to 1/2-inch green


Swollen bud

Bud burst

Sweet Cherry:

Swollen bud

Bud burst

Tart Cherry

Swollen bud

Swollen bud to Bud burst



Bud burst


Swollen bud

Bud burst


Apple (Ginger Gold): Half-inch green

Apple (McIntosh): Half-inch green

Apple (Delicious): Green tip

Pear (Bartlett,Bosc): Bud burst

Peach: Green tip

Sweet Cherry: Swollen bud

Plum: Swollen bud


Pest Focus

Green Fruitworm flight began today, 4/14

1st flight of Spotted Tentiform Leafminer and Redbanded Leafroller today, 4/14.
Pear Psylla egg-laying increasing



(Art Agnello, Entomology, Geneva)

       Even those of us who are loathe to yield to the frenzy that accompanies the early season will have to admit that things have been fairly calm and gradual so far this spring.  Some warmer temperatures this week will definitely get us on our way to being beyond busy, but there's still time to set a few pest program priorities before they're actually buzzing around your ears.  Not all of the following appearances will occur during the next week, of course, but just to keep you from being taken by surprise when all the excitement begins, here's a brief checklist of some prebloom arthropod activity to consider before the season barrels in.

Overwintering European
red mite eggs
Rosy apple aphid nymphs
Adult female San Jose Scales
Pear Midge larvae
Damaged fruits infested
with Pear Midge

   Mites: Oil applications should go on before we reach pink in apples or white bud in pears, and as there's not much freezing weather in the extended forecast, any calm period of sufficient duration would be a suitable spray window.  Start with 1.5-2.0% through half-inch green, and reduce to 1.0-1.5% as the trees reach tight/green cluster.  Also, don't forget the value of this tactic in stone fruit plantings (cherry, peach and plum) with a history of ERM.  Alternatively, in apples, ovicides like Savey and Apollo can be delayed until pink, and if your time evaporates and a miticide application before bloom is impossible, consider Agri-Mek or Zeal at petal fall in problem blocks.  Besides saving some time during the hectic prebloom period, this also makes sense as a rotation program for purposes of resistance management.

   Rosy Apple Aphid: In particularly susceptible varieties like Cortland, Ida Red, Golden Delicious, or R.I. Greening, a material such as Lorsban or Supracide can provide effective prevention through tight cluster, and will also help against San Jose scale at the same time.  Actara is another good prebloom fit for rosy apple aphid and other pests besides, including leafminers and early plum curculio.  You'll also get some side rosy control if you're using Esteem for scale at this time.

   San Jose Scale: In addition to the Lorsban and Supracide noted above, delayed dormant oil applications will do a good job of reducing scale populations.  If you're not treating for rosies but are concerned that SJS might be increasing in some blocks, Esteem is an insect growth regulator with good activity on scale.  The label calls for it to be mixed with oil, so if you're applying oil for mites anyway, this might be a tactic to try in severe cases.

   Dogwood Borer/American Plum Borer: A coarse spray of Lorsban directed at trunk burr knots between half-inch green and petal fall is the most effective tactic against both species, which can be a particular problem in dwarf plantings.

   Pear Midge: The first adults generally appear when Bartletts and Clapps are in the swollen bud to tight cluster bud stage, but no successful egg-laying occurs until the flower buds are a little more developed.  It may be too late in some spots, but in pear blocks with a history of midge infestations, concentrate on those portions of the orchard most protected from the wind by trees, high ground, or buildings, as the midges tend to be most numerous in these spots.  Organophosphates like Guthion are the most effective materials; 2 sprays are recommended, one between swollen bud and first separation of the sepals, and another 7 days later (or at white bud, whichever comes first).

   Pear Psylla: If you're just starting on your oil sprays, one application at 2% or two at 1% until white bud should provide adequate protection against egg deposition until an insecticide spray might be elected.  A number of newer materials have shown good activity in suppressing psylla numbers at white bud or after petal fall, including Actara, Assail, Calypso, and Esteem, in addition to the more traditional pyrethroid products (e.g., Asana, Danitol, Proaxis/ Warrior).  Agri-Mek used shortly after petal fall has given good control if applied correctly (well-timed, adequate coverage, combined with an oil adjuvant), and split applications of Nexter or Provado, also starting soon after petal fall, will help keep nymph numbers down through the early summer.

   Oriental Fruit Moth: The first adults could start flying during the next two weeks, depending on how much of a warming trend we get, and pheromone disruption starting against this brood in peaches or apples is an option, although bear in mind that your plum curculio sprays will serve double duty against OFM as well.  However, be prepared to start these at petal fall even in peaches, as shuck split will be too late to get the first egg-laying moths.

   Black Cherry Aphid: In (especially) sweet cherry plantings having a history of infestation by this pest, which curls and stunts the leaves, a prebloom inspection for these shiny black metallic insects can warrant an application of Thionex or a pyrethroid (e.g., Asana, Baythroid, Warrior).

   Tarnished Plant Bug: Early season feeding by overwintered adults in peaches can damage flower buds and cause bleeding of sap from twigs and shoots.  If you note several bleeding sites per tree, a pink application of a pyrethroid can offer some control.  In apricots, choose Asana, Baythroid, or Warrior.  This is a an appropriate time to keep in mind that satisfactory control of TPB is more likely with appropriate management of orchard weeds that attract this pest and act as alternate hosts.




(Art Agnello, Entomology, Geneva)

We'll try this one more time:
On pears, the yearly seasonal maximum amounts per acre of azinphosmethyl active ingredient (NOT formulated product, as erroneously stated in the Mar. 31 issue) allowed are:
2008: 3 lb
2009–10: 2 lb
2011–12: 1.5 lb
Let's hope the season isn't over by the time I finally get this right.