Regeneration Potential of Six Habitat Types Common to North-Central Wisconsin

Abstract

Abstract The arboreal regeneration of 24 mature, fully stocked forests distributed among 6 common habitat types (Kotar et al. 1988) in north-central Wisconsin were studied. Nineteen of the stands were inventoried in 1992 and 1993; in 1993 an additional 5 stands were included. The density and composition of small (<25 cm) and large (25-150 cm) seedlings were determined, and the relationships of the understory and overstory were investigated. No significant (P < 0.05) differences were found for seedling densities of either size class among habitat types. This was due, in part, to the large variation within most habitat types; this in turn is primarily a function of the temporally variable nature of seedlings. The average densities per habitat type ranged from 3,125-20,200/ha for large seedlings and from 20,208-152,083/ha for the small seedlings. Red and sugar maple strongly dominated the regeneration. Red maple was the most common (88-96%) species in the small seedling size class on the three driest habitat types, and sugar maple (88-99%) on the two most mesic habitat types. In the middle of the site quality gradient, the two maples shared dominance with northern red oak. The level of maple dominance was lower in the large seedling class, ranging from 53-93%. The small seedling size class was significantly related to the amount of maple basal area each year, but the strength of this relationship weakened from 1992 to 1993. The widespread domination by red and sugar maple is a function of their regeneration ecology, shade tolerance, fire suppression, and deer browsing. The seedling composition and densities have important implications for the management of these forests. The regeneration and overstory characteristics suggest that it would be easiest to direct the composition one of several ways on the PMV and AVVib habitat types. Fairly heavy overstory treatments, in conjunction with seedbed preparation, are probably necessary to regenerate significant amounts of species other than sugar maple on the two most mesic habitat types. North. J. Appl. For. 15(3):116-123.