SUMMARY
By phytoconikal investigations (Braun-Blanquet 1951 1964) at sevcral locations of Serbia weed association as. Galeopsi-Calystegietum sepii Stepi) 1984 (=as. Galeopsistetrahit Calystegia sepium). Was established in spring small grains (spring Barley and Oats). Association consists floristicaly from 92 species from 30 families and 17 floral elements,
Characteristic (Dominant) group consists of Galeopsis tetrahit L., Calystegiascpium (L) R. Bf., Cirsium arvense (L) Skop„ Convilvulus arvensis L., Galium aparinc L. , Ranunculus arvensis L. , Polygonum aviculare L.. P. convolvulus L., Viola arvensis Murr., Sonchus arvensis L, Agreopyrum repens (L) Beauv., i Chenopodium album L. The weed covering value of dominant species was 93.41% from total covering value of association. Mein protection of mentioned crops from weeds therefore must be directed on species from characteristic group of association.
Established association have terophytic character with significant participation of hemicryptophyta and geohyta (tab.2). Species of floral elements with broad incidence dominate in this association (tab. 3).
Weed community as. Galeopsi-Calystegietum sepii Stepi} 1984. grows on higher altitudes of 450 m. Significant similarity with other weed association ot small grains on territory of Serbia was established.
Key words: Barlez, Oat Weeds, Vegetation, Lifeform, Floral Elements