Identification of the species in the Panicum capillare complex (Poaceae) from eastern Canada and adjacent New York State

The Panicum capillare complex was examined in eastern Canada and New York State, United States. Uniform cultivation indicated distinctive growth habits for the five species. Univariate analysis of various morphological characters indicated some that were useful in species identification, especially when expressed as ratios. Discriminant function analysis of 4 floret characters in 128 samples and 13 morphological characters (including the 4 floret characters) in 48 samples indicated that floret characters, especially those related to overall size and shape (area and perimeter), were most informative. Various ecological and morphological characters useful for identification of the species are discussed. A key to the species is presented. Key words: Panicum capillare, identification, weeds.