If you are having troubles with Ash trees take a look into this article: Controlling Emerald Ash Borer               

Here is a writeup from NDSU about how the recent weather pattern may push back when you decide to turn cattle out to pature: Extreme Weather Expected to Delay Pasture Turnout

Here is some information about dieases, disorder, and invaders you may encounter: Black Knot, Dutch Elm DiseaseCedar Apple Rust, and Winter Burn

The link to the ND Tree I.D. & Information Book is here.