[Notes on the present status of the segetal floristic element in Leningradsky region]
1997
Kravchenko, O. (All-Russia Plantbreeding Institute named after N.I.Vavilov, Sankt-Peterburg (Russian Federation))
The report deals with the results of the usual regular inspection of weeds in Leningradsky region in 1994-1996. During the inspection the main attention was paid to malicious weeds as well as to the newly-appeared weed species. The description of fields and that of the weed composition were made as well as a herbarium was compiled. The weediness of crops was determined according to Maltzev Scale. The results of the inspection show little changes in the basic weed composition in the last 10 years. The population of specialized weeds is decreasing, some previously wide-spread weeds have disappeared. However new species appear that can be dangerous as noxious weeds in future
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