Ok, I found a few public area's there to hunt:
http://co.washington.ia.us/departments/conservation/parks.htm
English River Wildlife Area looks to be the most promising spot
<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">If you enjoy hunting, trapping, hiking, or horseback riding in areas which are rugged and undeveloped, then the English River Wildlife Area is for you. This 673 acre mini-wilderness features the junction of the North English and South English Rivers, several marshes, and a good interspersion of bottomland timber, crops, and grassland.
Primarily managed for wildlife, the English River Wildlife Area attracts huntable populations of waterfowl, deer, and pheasant. It also contains small numbers of wild turkey, squirrel, and rabbits. Trapping and hunting for raccoon is especially popular there, with some fox, mink, muskrat, and coyote also being harvested.
Non-game enthusiasts will find large populations and diversity of a wide range of wildlife species. Bird species range from bluebirds to marsh wrens, plants from duck weed to oak trees, and animals from shrews to white-tailed deer.
Parking areas are located along the south and west ends of the area. Be sure to include your compass, waterproof boots, and insect repellant as you explore this area.
Location
Northwest corner of county. On Highway 22, take Birch Ave. north. On 120th St., either continue north or turn left to other sections</div></div>