Greetings Blake!
The three most common tree planting cost-share programs offered in Illinois include the Forestry Development Act (FDA) cost-share program, Conservation Reserve Program (CRP), and Environmental Quality Incentives Program (EQIP).
FDA: Illinois Dept. of Natural Resources (DNR) sponsored program funded through the mandatory 4% harvest fee levied on all timber sales in the state. A minimum of five acres and a forest management is required for enrollment. Contact your local DNR forester for more information http://dnr.state.il.us/conservation/forestry/DISTFRSTMAP.pdf
CRP: This federal program is sponsored by the United States Department of Agriculture (USDA) Farm Service Agency (FSA). Certain land-use, tenure, and agriculture history requirements are necessary for enrollment – no minimum acreage. To determine whether your land qualifies, please contact your local FSA office http://offices.sc.egov.usda.gov/locator/app?state=IL&agency=fsa
EQIP: This federal program is sponsored by the USDA Natural Resources Conservation Service (NRCS). Certain land-use, tenure, and agriculture history requirement are necessary for enrollment. To determine whether your land qualifies for EQIP, please contact your local NRCS office http://www.il.nrcs.usda.gov/contact/directory/ilcntys.html
Please note that there are additional state and federal conservation programs available for private landowners in the Illinois. For more information on state sponsored tree planting (forestry) programs, please contact your local DNR district forester http://dnr.state.il.us/conservation/forestry/DISTFRSTMAP.pdf
Good luck and happy tree planting!