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Weed control of saltbush / orache (Atriplex sp.) in sugar beets
Summer 2017 on the Lower Rhine. Later use, saltbush partly 1 m higher than sugar beet. Older plants with high stalk strength, cutting therefore difficult but possible. First cutting a few weeks earlier and then followed by another cut. These experiences are collected in the first year of tests.
Knife adjustment 6/45, working speed 8km / h
Weed control of charlock / wild mustard in winter wheat
Spring 2014; 1st pass at the right time, here in the upper leaf zone in the inventory “combed and cut”. For this, the weeds must stand out clearly from the crop, the cut is then made on the stalks. If the weeds are at the same height as the crop, the flower heads are largely pushed away and not cut. Blade setting 4/50, operating speed approx. 12 km / h
Exotic use of CombCut in the Netherlands: Combcutting cuckooflower.
Under good conditions and with some experience, such measures are also possible. Will always be the absolute exception. If the wind is “reversing”, the result may change significantly in combating cuckooflower / lady’s smock / mayflower / milkmaids (Cardamine pratensis). But in this case the result was approved.
Knife setting 4/50, speed 8 km / h
Selective cutting of thistle as effective as MCPA herbicides
Independent research shows that the use of the CombCut weed cutter is as effective in controlling thistle as the use of MCPA herbicides. The machine has also proved to be of much greater versatility, and as resistance increases, the interest from conventional growers increase. “If there is a physical difference between crop and weed, you can basically cut anything,” says Jonas Carlsson, the inventor of CombCut.
The new reported research trials have been conducted in spring wheat in Sweden in 2015 and 2016 with equivalent results. The researchers from Swedish University of Agricultural Sciences, who conducted the research, shows that the weed cutter reduces the thistle seed production by a thousand times, which is comparable to the control with herbicides in spring or autumn. This also causes a fatigue of the thistle roots with 66-79%, as demonstrated also in previous trials. The researchers found that after two growing seasons herbicides kill a large number of thistles, while repeated weed control with CombCut also results in a gradual fatigue of the root bio mass of the thistle. This even leads to a higher reduction of thistle shoots in the long term, compared with spraying.
– It is an important outcome that we can now start communicating. We have a great interest from countries where they have increasing problems with resistant weeds. There are always new things around CombCut. For example, there are several new ongoing tests regarding the effect on docks (Rumex sp.). Using CombCut has also shown to give good results in autumn-harvest crops, for example in rapeseed. The effect has been beyond expectations, “says Jonas Carlsson, Just Common Sense Ltd, the inventor of the machine.
Soon automatic setting will be possible from the cabin
CombCut is a Swedish invention, specifically designed for organic production of cereals and grassland. At present, about 20 machines are sold annually in Sweden and around 300 are now in use in some 20 countries. There is one that rolls in Australia (Tasmania), 33 in Canada and the first 12 have now also been sold in the United States. New for this year is also the development of a 9-meter machine.
– Other development projects we work with are automatic setting from the cabin. This would simplify and shorten the set times considerably. I hope that we can achieve this within a couple of years. Another thing is collection, so you can get cut-off weeding seeds such as wild oat and black grass that you do not want to leave on the field. One might also imagine using the machine to comb out insects in case of acute attack, for example, of rape pollen beetle. We are also looking in to how we can further refine the selectivity of weeds in the crop. says Jonas.
Small harvest reduction
But at Slatte Ekodag (a Swedish organic fair) last year we used it at 22 km / h. It works if it’s a flat, smooth field, but maybe nothing I recommend anyway. Best results are also if you use it more than one time. You get about 70 percent of the weeds when cutting the weeds with CombCut, “says Jonas. The machine’s function is based on the physical difference between crop and weed. Therefore, if you use it when the difference is biggest, you get the best results. The greater the difference, the easier it is to find the right settings.
“Most often, it’s just before the cereals spike develops and the straw starts to grow. Then the thistle is also most vulnerable. If you use CombCut at this stage, you cause a lot of damage to the thistle and it is out of competition. But you can cut later if you drive higher up in the straw but below canopy. You can also cut above the canopy of the crop and cut weeds that is higher than the crop, you can go very close to the canopy. Then when the spike emerges through the straw it becomes more sensitive.
Even in those occasions we cut late and it seems to be hard to use CombCut in the field, we do not usually see a larger crop reduction than a maximum of 10 percent. Mostly none. What can happen is that the crop in the worst case will shoot laterally if you cut late and damage it too much, “says Jonas.
The machine was developed primarily for thistle, but since then more uses have emerged.
-The first generation CombCut was developed for thistle control in spring-seed crops. Then growers themselves have tried out and found new uses. Timing is important, but you get a feeling for how to use it after some experience. The setting of the machine is made by loosening a screw and adjust it a little bit until the knives get the desired position. The angle of the knives is determined by the stiffness in the direction of driving and of the stalks thickness at the tilt angle. The stiffer and thicker weeds are the sharper the angle should be. You look at the height of crop and weeds and see where the physical difference is greatest in, for example, thickness.
Can cut anything
The aim is now to establish the machine at more markets, for more applications and for more users
“We see a large market in North America and we will hire more people in the long term. In future, we will also test the machine more in combination with chemical / biological control. Our goal is also to reach conventional agriculture. Each drop of chemicals that can be spared is good. There are more uses. For example, I have used the machine for top pruning field beans myself, and it’s fine, just do not cut too deep in to the crop. CombCut has also been used för top pruning hemp. In the case of weeds, one can say that there is a physical difference, one can fight in principle anything!
Dad: Jonas Carlsson
Sales start: 2009
Total number of machines sold: 300
Production 2018: 75 machines, of which 20 sold in Sweden
Export: 20 countries
Some uses: bluebell, black grass, poppy, goosefoot, thistle, wild oat, docks, amaranth …
CECILIA RYEGÅRDEKOWEB No. 4 • May 16, 2018
To English by Just Common Sense Ltd