Early revegetation of clear-cut and burned jack pine sites in northern lower Michigan

Abstract

Revegetation of clear-cut and (or) burned jack pine (Pinus banksiana Lamb.) sites in northern lower Michigan was characterized during the first 5 years following treatment. Burning promoted the establishment of a large variety of species not typical of unburned areas. A total of 89 species was recorded on burned sites, of which 40 were exclusive, compared with 51 species on unburned sites, of which only 2 species were exclusive. Burned sites consistently showed greater species richness compared with unburned sites of the same age. Low species diversity on the older unburned clear-cuts (years 3 to 6) and certain burned sites was directly influenced by the dominance of the sedge Carex pensylvanica. The total domination of Carex (up to 86% relative cover) on many of these sites appears to be unique to northern lower Michigan. It is hypothesized that Carex, acting as an opportunistic species, monopolizes the space and soil resources liberated following disturbances and suppresses or excludes other species.