Washington Grove Forest Volunteers Needed. The Washington Grove is an old growth oak/hickory forest at Cobbs Hill Park. Join us as we help the City protect the trails in this beautiful woods by the reservoir by spreading wood chips. We’ll give you a task you can handle- all ages welcome.Bring work gloves and rake if you have them. Dress for the weather. Rain or shine. Meets at the end of Nunda Blvd. at Cobbs Hill