Leafminer. I did find one orchard today with high levels of leafminer. Leafminer mines are easy to see now from the upper leaf surface. The white poke-a-dotted mines are primarily on fruit cluster leaves. Threshold for leafminers are not exact. Let’s say if you find 1 mine for every 2 clusters, consider applying Provado or Calypso when the next generation mines are small, probably at the end of June or early July. Here's an old leafminer factsheet, but there are good pictures. Click on the "tent-like appearance" in the Larvae section of the factsheet to see what the tissue feeding mines look like. http://www.nysipm.cornell.edu/factsheets/treefruit/pests/stlm/stlm.asp
Last week I said unsprayed European apple sawfly should be moving into second fruits soon; well I started seeing them in second fruits on May 30. Unsprayed (or attempts at organic control) European apple sawfly damage can get pretty messy looking with lots of reddish-brown frass, but an insecticide spray should stop them advancing into additional fruits. Here's a Cornell factsheet: http://www.nysipm.cornell.edu/factsheets/treefruit/pests/eas/eas.asp
Continue to check your trees for developing apple scab lesions. If you find lesions, apply full rates of Captan or Captec 7-10 days apart. The hot, dry weather forecasted plus Captan is probably the best way to attack active scab lesions.
Next message on Tuesday, June 10th (949-1456)