Structural and functional attributes of the vegetation of northern mixed prairie of North America

Abstract

This paper reviews and interprets the structural and functional attributes of the vegetation of northern mixed prairie and examines the productivity of the northern sites in the perspective of other related grasslands in North America. The northern mixed prairie is dominated primarily by cool-season species ( C3), although the existence of two temporal guilds, one of cool-season and the other of warm-season ( C4) species, is a characteristic feature. Because of the different amounts of cool- and warm-season components, the period of peak growth varies among sites. The differential seasonal expression of these species causes plant diversity to vary with time, with a maximum value during the midseason. Further, topography, climate, soil and grazing modify the balance between the two guilds, and consequently there may be a considerable amount of dissimilarity among the communities developed on different sites. Aboveground net production for the majority of sites is in the range of 100 to 300 g-m^-2.y^-1; however, the communities transitional to true prairie may yield ≥ 500 g.m^-2.y^-1.