The estimation of frequency of weed appearance in Slovene fields
2001
Lesnik, M. (Maribor Univ. (Slovenia). Agriculture Fac.)
On the basis of random weed surveys, which were carried out from 1990 till 2000 in 300 places in Slovenia, the frequency of appearance for 793 plant species that can be considered as weeds was estimated. Also the estimation of changes in frequency of appearance in contrast to the appearance in the past was done. It was estimated that 19,3% of weeds are appearing more frequently than in the past periods of time, 36,2% of weeds are appearing less frequently, and 44,5% of found weeds are appearing with the same frequency as in the past. By considering the frequency of appearance and other biotical properties of each of 793 weeds, the estimation of their present economic importance was made. 618 species were classified as weeds without economic importance, 139 as weeds with small economic importance, and only 36 species were found to be economic important weeds.
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