Contact(s): Lisa Pitzer, park manager, 608-996-2261
CASSVILLE, Wis. - A private contractor tree service has begun removing diseased and dead trees from Nelson Dewey State Park, resulting in some temporary road and trail closures. The Department of Natural Resources has approved a timber sale within the park to remove trees that are dead and dying from oak wilt disease, which could present a hazard if left standing, as well as trees in affected areas to slow the spread of the disease. The sale will be finished this winter in time for staff to plant additional trees in Spring 2018 which are resistant to oak wilt.
Nelson Dewey State Park overlooks the Mississippi River from a 500-foot bluff offering a rich history and a variety of outdoor activities, including camping, hiking, and picnicking. Beautiful mature oak trees in the campsites provided an appealing natural setting and shade for campers. However, oak wilt has killed many mature oak trees in the campsites.
In 2015 active oak wilt management was implemented, with trenches to limit the below-ground spread of oak wilt in the family campground. Unfortunately, several individual trees that were located away from the original disease centers were found to be actively wilting during the summer of 2016. It is likely that these trees were infected through overland transmission by insects. Follow-up trench work was conducted in December 2016 and November 2017 to minimize the risk of below-ground spread at an early stage.
Oak wilt is a fatal disease caused by the fungus Ceratocystis fagacearum that has led to the death of thousands of oak trees annually. Since the first identification of the disease in 1944, the disease has spread throughout the southern two-thirds of Wisconsin. Every year, oak wilt kills many oak trees in Wisconsin. This disease is an especially serious problem for trees in the red oak group, such as northern red, northern pin, and black oaks. Once wilting symptoms become visible, an infected tree loses most of the leaves and dies very quickly, often within one month.