A WEED SURVEY OF PEDIGREED ALFALFA SEED FIELDS IN MANITOBA
Autor: | I. N. Morrison, M. S. Goodwin, A. G. Thomas |
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Rok vydání: | 1986 |
Předmět: | |
Zdroj: | Canadian Journal of Plant Science. 66:413-416 |
ISSN: | 1918-1833 0008-4220 |
Popis: | Weeds were counted in 77 pedigreed alfalfa (Medicago sativa L.) seed fields located throughout Manitoba. The five most abundant species were all perennials: quackgrass (Agropyron repens (L.) Beauv.), dandelion (Taraxacum officinale Weber), Canada thistle (Cirsium arvense (L.) Scop.), bluegrass (Poa spp.), and perennial sow-thistle (Sonchus arvensis L.). Quackgrass occurred in 65% of the fields with a mean field density of 23.4 culms m−2, the highest density of any of the species. The next four most abundant species were annuals with narrow-leaved hawk’s-beard (Crepis tectorum L.) having the highest mean field density for annual species at 2.9 plants m−2, although it occurred less frequently (30%) than the other three annuals, wild buckwheat (Polygonum convolvulus L.), wild mustard (Sinapsis arvensis L.) and wild oats (Avena fatua L.).Key words: Weed survey, alfalfa, quackgrass, narrow-leaved hawk’s-beard |
Databáze: | OpenAIRE |
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