Germination of weed seeds. I. Longevity, periodicity of germination, and vitality of seeds in cultivated soil.
CHEPIL, W. S.
Soil Res, Lab., Swift Current, Saskatchewan.
Scientific Agriculture 1946 Vol. 26 pp. 307-46
Language of Text
The two parts of this study deal respectively with the nature and degree of dormancy of seeds of different weeds, and the methods of cultivation which might facilitate their eradication. Table 1 gives data for longevity of weed seeds of many species.in clay, loam and sandy loam, and this is followed by graphs showing the yearly total of seedlings emerging from cultivated soil during the 5 years after sowing. The lengths of dormancy are classified as: none to very short (max. not exceeding 1 year); short to intermediate (max. 1 to 3 years); long to very long (max. exceeding 3 years). The number of species, in each class is six, twelve and forty respectively; allowing for borderline cases, about thirty species possess a very long period of dormancy in cultivated soil and it is these which, when present in large numbers, constitute a serious agricultural problem; for some no practical method of complete eradication is known. Periodicity of germination is also recorded, according to season of year.