Technology is getting rid of herbicides and hand-weeding. Woohoo!
Vegetables like lettuce, broccoli, tomatoes, and onions and called “speciality crops” because they aren’t mass-produced like corn, wheat and soybeans. There are a lack of good herbicides to get rid of weeds when growing these crops. So, a lot of hand-weeding happens, especially for organic crops, where the farmer can’t use chemicals to kill weeds anyway. Over in the U.S., as labour costs rise, there is a new demand for an alternative. Hand-weeding is slow and increasingly expensive: it can cost US$150-$300 per acre. So interest in robot weeders is peaking.
The U.S. are a little behind Europe, however. Here, there are more incentives to grow organically with fewer pesticides, so European growers have been using robotic weeders for some time. Although, these systems need improvement. Says Steven Fennimore, of the University of California. “I’ve been working with robotic weeders for about 10 years now, and the technology is really just starting to come into commercial use. It’s really an economic incentive to consider them.”
Fennimore has been working with university scientists and companies to see how the existing robot weeders can be improved. The weeders utilise tiny blades that pop in and out to uproot weeds without damaging crops. He says that although the technology isn’t perfect, it’s getting better and better. The weeders are programmed to recognise a pattern and can tell the difference between a plant and the soil. While they currently have trouble telling the difference between a weed and a crop, companies have made some breakthroughs while training the machines to tell a lettuce plant from a weed. Fennimore is also working with university engineers on a system to tag the crop plant so the weeders will avoid it.
“The problem with the machines right now is that they are version 1.0, and there’s tremendous room for improvement,” he says. “The inability to be able to tell the difference between a weed and a crop requires the grower to be very exact when using them. The rows have to be a little straighter, cleaner, and more consistent because the machines aren’t that sophisticated yet. The robots don’t like surprises.”
The robotic weeders currently on the market cost between US$120,000 and US$175,000. For some growers, it is a better long-term option than expensive hand-weeding. Others think it’s a lot of money for a new technology, and are waiting for it to get better and cheaper.
Fennimore is focusing his work on physical control of weeds because it offers the best option. He’s also started working in crops besides lettuce, such as tomatoes and onions. He adds that each crop will require a different system. “I believe what makes the robotic weeders better than herbicides is that this electronic-based technology is very flexible and can be updated easily,” he says. “We all update our phones and computers constantly, which is a sign of a robust and flexible technology.”
So if you are a farmer, then your weeding days could soon be over. Robot slaves, we welcome you!