Preliminary Report on Weed Survey in Sunflower Field in East Region of Heilongjiang Province

Sunflower field weed survey was conducted using an inverted W-pattern with 9 sampling points in the east region of Heilongjiang province.The results showed 55 weed species recorded in sunflower fields.There were 43 broad-leaved weed species accounted for 78.2%,9 the grass family for 16.4%,3 others for 5.5% among 55 weed species.30 species of annual weeds in 54.5%,7 species of annual or more years old weeds in 12.7%,18 species of perennial weeds accounted for 32.7%.Appear frequency of 10 weeds were over 50%,they were Barnyard grass(Echinochloa crus-galli),Goosefoot(Chenopodium album),Copperleaf(Acalypha australis),Chinese Mosla Herb(Elsholtzia ciliata),Gold Setaria(Setaria glauca),Field Sowthistle Herb(Sonchus brachyotus),Siberia Cocklebur(Xanthium strumarium),Bottle Brush Herb(Equisetum arvense),Redroot Pigweed(Amaranthus retroflexus) and Dayflower(Commelina communis).Those 10 weed species were important weeds in sunflower field in the area.