Apple IPM Report - April 24, 2012

• Codling Moth
• Aphids
• Spotted Tentiform Leafminer
• Plum Curculio
• European Red Mite
• Apple Scab
• Fireblight

Dean Polk, Fruit IPM Agent and
David Schmitt, Eugene Rizio and Atanas Atanassov,
Program Associates, Tree Fruit IPM
See Scouting Calendar and Trap Counts


Codling Moth (CM): Timing for CM treatments are updated in the following table: Biofix points (the first sustained trap catch) were recently set in central and northern counties (Hunterdon County – 4/21). Insecticide timings are predicted in the following table based on degree day accumulation predictions from Skybit.

Codling Moth Degree Day Timing
	Application and Insecticide Type
County Area	Rimon: 75-100DD + 14-17 days later Intrepid: 150 + 450 DD			Intrepid 150 + 450 DD Diamides - Altacor, Voliam mixes: (150-200 DD) + 14-21 days later		Cyd-X, Carpovirusine 250 DD + every 7-9 days during brood hatch (later if first spray is an IGR)	Standard Insecticides, Diamides – Belt, Tourismo 250 DD + 550 DD
DD	50	100	150	150	450	250	250	550
Southern	4/17	4/21	5/1	5/1	5/26	5/11	5/11	5/31
Central	4/27	5/3	5/6-8	5/6-8		5/18-20	5/18-20
Northern	5/3	5/6-8	5/15-19	5/15-19		5/25-28	5/25-28

Aphids (Spirea and Apple Aphids, and Rosy Apple Aphids): The apple aphid complex of green and spirea aphids is starting to become active. A threshold of 50% terminals infested should be used to determine the need for treatment. If predators are present, treatment can be delayed unless aphid populations are very high. A few rosy aphid colonies have been seen above treatment threshold. The rosy aphid threshold for treatment is an average of one colony per tree. We have seen some early predator populations that can suppress aphid growth. If using Assail or Calypso for Codling Moth control later, then aphids will be controlled at that time, since these materials will do “double duty” for both Codling Moth and aphid control. Any premix like Voliam Flexi that has a neonicotinoid in it will also control aphids when used for Codling Moth a few weeks from now.

Spotted Tentiform Leafminer (STLM): Very few leafminers have been seen to date. We generally do not want to treat at this time unless the mine count exceeds .5 mines per leaf.

Plum Curculio (PC): Of the newer insecticides, Actara, Calypso, and Avaunt give good control, and Imidan still works well. Voliam Flexi (Rynaxypyr + Actara), Voliam Xpress (Rynaxypyr + Warrior), and Leverage (Provado + Baythroid) are broad spectrum and will control all key pests at this growth stage. Since Voliam Express and Leverage are premixes with pyrethroids, they need to be used at the high rate to achieve PC control. Therefore, they cost a little more than you may want to spend this early in the game.

European Red Mite (ERM): Petal fall to first cover is a good time to apply the miticides Apollo or Savey, especially if you plan on using a harsh pyrethroid program. These miticides should be included in a rotation program for mite resistance management. Onager has the same active ingredient as Savey, but Onager is a 50% WDG, and Savey is an 11.8% EC. Zeal has a similar mode of action as do Apollo, Savey and Onager, so it may work best early in the season. Envidor should also be used on young developing mite populations, but has a different mode of action than the previously mentioned products. Several Red Delicious blocks in southern counties already have mite populations above the 2 mites/leaf treatment threshold, which is likely a result of pyrethroid use last season.

Apple Scab: Scab has not been found in any blocks to date. The wetting period we just experienced was the first major infection period during the last several weeks. We have a prediction for a second infection period this coming weekend through Monday. Remember to also include materials that are effective for Cedar Apple Rust at this time of year.

Fireblight: Fireblight is a concern anytime there is wetting or high humidity combined with warm temperatures. Where blossoms are still present in northern counties, effective antibiotics should be applied whenever conditions are suitable for infection.