Planting trees is one of the best ways to "give something back " to the land. The thing I like about trees is once they are established, they are prettymuch self refilling feeders. An oak tree may not drop acorns every single year, but they are usually consistant. If you plant the right variety it is possible to have acorns every year. I am trying to get rid of a bunch of last years nursery overstock. If anybody is interested I have 3gal. oak's. Sawtooth, Swamp Chestnut, Nuttall, Shumard, and others!

So what varietys grow nuts every year and which would grow best in northern climates.

Any oak in the white oak family usually produce every year, while most red oak species drop every other year. All of these species will do ok in a northern climate.

Good info Dirtyhands. Quercus spp. specimens are hard to beat and many do actually grow fairly rapidly once established.