OAK REGENERATION AND OVERSTORY DENSITY IN THE MISSOURI OZARKS

Reducing overstory density is a commonly recommended method of increas ing the regeneration potential of oak (Quercus) forests. However, reco mmendations seldom specify the probable increase in density or the siz e of reproduction associated with a given residual overstory density. This paper presents logistic regression models that describe this rela tion for a forest in the Ozark Highlands of Missouri that has been man aged for 40 years by the single-tree selection system. In general, den sity of oak reproduction of a given size increases with decreasing res idual stand basal area. However, the corresponding increase in the rep roduction density at all levels of overstory density indicates low pre dictability of individual stands. The models nevertheless describe the average trend in the highly stochastic regeneration process. They als o suggest that stand densities must be kept low (e.g., basal areas <14 m(2).ha(-1)) to sustain the requisite recruitment of reproduction int o the overstory under the single-tree selection method.