I don't know if any of the folks here ever use the NEWA website from cornell. It's a pretty handy pest control info source if you happen to have one of their weather station reporters nearby.

It used to be just a handful of stations in upstate NY and a couple in VT....now they have tons all over the northeast. It has likely been growing gradually for several years I just had not noticed.

The site has built in degree day calculators that use the local weather station info in conjunction with user adjustments like local bud-break and petal fall dates to predict pest activity and disease pressure for a large number of problems for a number of crops (apples included)

http://newa.cornell.edu/

hope some of you find it helpful in targeting your control measures.