ROUNDUP (WATER SOLUTION) USE AGAINST FIELD BINDWEED <i>(CONVOLVULUS ARVENSIS L.)</i> ON FALLOW FIELD
Field bindweed is a very common weed nowadays. From 1993 to 2003 the area infested by field bindweed in West Siberia has virtually doubled due to its high competitive ability. Upon rooting, field bindweed is difficult to eradicate by hoeing as it is can grow again from the depth of 40 cm. The most effective method to control field bindweed is a chemical spraying on a fallow field. That enables herbicide affecting the weed at its most vulnerable growth stage. Glyphosate herbicides are often used to spray a fallow field however the technology of their use against field bindweed is insufficiently developed. Therefore, the research purpose was to study the effect of a glyphosate herbicide Roundup, water solution, on field bindweed. The research objective was to evaluate the herbicide effectiveness against field bindweed and to define its optimal spraying rate. It has been revealed that to kill field bindweed in fallow, two hoeing operations should be performed in the first half of summer to kill annual and biennial weeds and to exhaust nutrient reserves of field bindweed. Then at the beginning of field bindweed flowering (when the runners length is about 40 cm), good results are achieved by Roundup, water solution, spraying at a sufficient rate of 4 L ha. Upon spraying, the herbicide needs at least 4 weeks to penetrate the weed root as deep as possible. Therefore, a fallow may hoed again upon the re-emergence of annual and biennial weeds or under winter.