Here are some forestry related sites you may find useful:

Trees and Wood:  An Identification Resource Guide

https://www.deckstainhelp.com/trees-and-wood-an-identification-resource-guide/

International Society of Arboriculture On-line - Trees Are Good
http://www.treesaregood.com/


National Arbor Day Foundation
http://www.arborday.org/


Wisconsin Department of Natural Resources
http://dnr.wi.gov/


Brown County Extension Agency
http://www.co.brown.wi.us/uw_extension/index.html