For those of you interested in spraying your apples, there was a post on GardenWeb’s forum by Alan Haigh aka harvestman. Its a great breakdown of what he has been doing with success in the New England area of the US for decades. harvestman always has great posts to read with a lot of applied knowledge, but this may be his best.
Posted by harvestman 6 (My Page) on Fri, May 11, 12 at 18:27
Here’s my spray schedule for the scores of orchards I manage around SE NY. It has functioned well for me for over 2 decades, although J. Beetles and brown rot of stone fruit increases the number of sprays some years some sites.
Dormant oil (this is optional if there were no mites or scale issues the previous season).
Do oil spray somewhere between the point where emerging shoots are 1/2″ and the flower clusters begin to show a lot of pink. Mix Rally or Immunox (myclobutinol) at highest legal rate with 1 to 2% oil. If it’s closer to pink use 1%.
Don’t spray again until petal fall when petals have mostly gone from latest flowering varieties and bees have lost interest. Than spray Imidan (or triazide or something equally affective) + Nova + Captan mixed together at highest legal rates (you may want to drop the Captan because of increasing concerns about health risks). Repeat in 10 to 14 days.
Where I manage orchards, the space between earliest flowering Japanese plums and latest flowering apples is only 2 weeks or so (not this year) which usually allows me to wait until the latest flowering trees are ready to begin spraying anything. Plum curculio seems to time its appearance conveniently to the rhythm of the last flowering apple varieties. This may not be true where you are.
If plums or peaches need oil they may need application before apples. Iï¿½ve only had mites on European plums here and never need oil for other stone fruit.
All this is based on plum curculio being the primary insect problem which is the case most areas east of the Mis. River. These sprays will also absolutely control scab, CAR and Mildew as well as most of the crop fatal insects. Apple fly maggot is an exception, but I haven’t had much of a problem with this pest in the orchards I manage. This pest can be controlled with a lot of fake apples smeared with tangle trap.
If you don’t want to use synthetic chemicals try 4 applications of Surround about a week apart starting at petal fall. You may need to start on earlier flowering varieties as soon as they drop petals. When weather isn’t too hot you can mix hort oil at 1% once or twice.
Stone fruit may require the addition of an application or 2 of Indar (Monterey Fungus Fighter is a similar chemical available in home orchard quantities) starting 4 weeks before first peaches ripen. Apricots must be sprayed sooner if they are scab susceptible with same compound.
Because I manage so many orchards so far apart I have to resort to a spray schedule that is based on expectations rather than actual monitoring. You may be able to reduce insecticide sprays with monitoring but PC can enter an orchard overnight and, if your insecticide lacks kick-back, which Imidan has, do a lot of damage in a couple of days.
Other problems may occur later in the season and you will in time learn to monitor and react to the pitfalls.
Good luck, Alan Haigh- The Home Orchard Co.