Woody Vegetation of a Disjunct Bur Oak (\u3ci\u3eQuercus macrocarpa\u3c/i\u3e) Forest in East-Central Nebraska

Woody plant composition was assessed for three tree-size classes in two ravines of Oak Glen Wildlife Management Area, a disjunct oak forest in Seward County, Nebraska, using Importance Values (IV) obtained by the Point-Quarter method. Bur oak (Quercus macrocarpa Michx.) dominated the large-size class (\u3e30 cm dbh) (IV = 258) but elms (Ulmus americana L. and U. rubra Muhl.) (IV = 130) dominated the forest in one ravine in the medium-size class (10-30cm dbh) and elm and hackberry (Celtis occidentalis L.) (IV = 114 and 27 respectively) dominated the small-size class (\u3c10cm dbh). Bur oak in the small-size was low in abundance (IV = 9) and was absent from one of the study transects. These data on tree-size distribution in the extant forest suggests that the forest is likely to succeed from one presently dominated by bur oak, which appears to have characterized the presettlement forest, to one dominated primarily by elm or hackberry. Current management is likely to encourage a continuation of this succession