A PRODUCT devised in Sweden as a means of controlling problem weeds in organic cropping systems has shown promise as a weed control tool in conventional farming as well, in particular for farmers with problems with herbicide resistant weeds.
Inventor Jonas Carlsson came up with the CombCut technology as a means to eliminate thistle from his cereal paddocks.
The cutter bar is set up so that when used in tillering cereal crops the skinny, flexible cereal leaves pass through, while the coarse weed stems are chopped off.
t can also be used to target weeds that are markedly taller than the crop species.
“If it is difficult to comb through the growing crop is it always possible to cut above and very close to the tops of the crop without going down and combing in it,” Mr Carlsson said.
“The whole idea about CombCut is that we use the physical differences between the weed and the crop.
“The bigger differences you have the easier it is to find good settings and to get a better result and vice versa, that is why it is very effective on thistles,” he said.
Mr Carlsson said timing was critical to CombCut’s success.
“You need to carefully keep an eye on the development of the field to get the best out of the system.”
Mr Carlsson said the hunt for non-chemical methods of weed control meant conventional farmers were seriously interested in the technology.
“It can be difficult to understand a totally new technology as we uses with CombCut, but I am surprised how easy it has been to sell it as soon they feel comfortable and understand the technology,” he said.
He said it had advantages over a sprayer in that it could be used in all weather, with no delays due to wind or rain.
Mr Carlsson said the second generation of the technology was more adept at identifying a wider range of weeds.
“It is possible to cut every kind of weed as long as you have a physical difference that you could use, whether it be height, straw stiffness or thickness.
Mr Carlsson said the CombCut technology had been tested as being as effective as the popular broadleaf herbicide MPCA for the control of thistle.
The study was conducted by a Swedish agricultural institution in Swedish conditions.
Another area CombCut may help with in Australia is the control of late season weeds, such as late germinating ryegrass.
The system has been used to control late season weeds in crops close to harvest, a time when chemical options can be difficult to manage due to maximum residue level requirements when selling the crop.