Crane's-bill and Shepherd's-purse appear to be on the increase in many arable rotations and the new rape herbicide Springbok offers improved control of these difficult weeds. The addition of the soil-active adjuvant Grounded has further added to its performance.
Dr. Mark Palmer, Technical Manager of Agrovista, has been concerned about the increasing threat of Crane's-bill and Shepherd's-purse for a number of years now. "Crane's-bill species are a real problem in many counties including Yorkshire, Nottinghamshire, Cambridgeshire and in the West on the lighter soils. As rotations have become tighter, they have been selected out in both cereals and in oilseed rape as some commonly used herbicides have little activity on them. Shepherd's-purse is a particularly difficult weed in Scotland and the North, so I am pleased that Springbok does such a good job on these weeds," says Dr. Palmer.
"We have been looking at Springbok in trials and have seen its excellent performance. We have also tested it with the specialist adjuvant system, Grounded."
According to Dr. Palmer, Grounded was specially designed for use with pre-emergence herbicides. "It works by reducing spray drift, improving the spray deposition pattern and increasing adsorption to soil particles, which increases the performance and reliability of residual herbicides. In BASF trials the addition of 0.2 l/ha of Grounded to 2.5 l/ha of Springbok applied pre-emergence improved the control of Crane's-bill by 13%, Common Field Speedwell by 5% to 100%, for Groundsel by 5% to 100% and Black-grass by 3% to 68% control."
"In five Agrovista trials, the addition of Grounded to Springbok raised the level of control of Crane's-bill by an average of 12%," reports Mark.
"Pre-emergence herbicides are crucial for the control of key weeds such as Crane's-bill and Shepherd's purse in oilseed rape. Springbok is a great new herbicide that controls previously difficult problem weeds. From my observations it has out-performed other herbicides on a number of key weeds. In moderate weed populations it does an excellent job on its own. On very high Crane's-bill populations, a sequence with a post emergence option has given very high levels of control. I have no doubt Springbok will be an important new addition to the herbicide portfolio for rape," says Mark.
Springbok can be applied pre- or early post-emergence, but for best results on problem weeds, application should be made pre-emergence. "Development work shows that there is some fall-off in control when the product is applied post-emergence. For instance in four trials, Springbok applied pre-emergence gave 97% control of Shepherds-purse but this fell to 76% when applied post-emergence. For five different species of Crane's-bill, the average level of weed control was 86% when Springbok was applied pre-emergence, but fell to just 43% post-emergence. This is still better than any other oilseed rape herbicide, but if you want to get the best level of control then pre-emergence is the best timing," concludes Diane Heath, BASF Oilseed Rape Product Manager.
