A Survey of the Forest Structure on the Peninsula at the Oak Lake Field Station

Leitheiser, K.M. and J.A. Krueger

We conducted a survey of the forest structure on the peninsula at the Oak Lake Research Station. Data suggests that the overstory is comprised of a low-density forest dominated by mature to overmature green ash and bur oak. Evidence indicates that that the oak suffers from endemic heart rot fungi and bacterial infection. We estimate the average age of the overstory bur oak to be 83 to 93 years (± 10 years sd) which places that origin near the time that the peninsula was subdivide for woodlots. The understory (midstory) component is comprised almost entirely of buckthorn and chokecherry. Oak and ash are nearly absent in the midstory but significant amounts of seedlings were present. Without some management intervention, we speculate that the continual decline of the oak-ash overstory will result in a replacement by a near continuous canopy of buckthorn in the next few decades. (Presentation pdf)