Friends or foes:
Farmers talk about their relationships with weeds
Patrick Lillard, Purdue University
Whether or not we like it, we all have relationships with those plants we call “weeds.” Farmers can use some colorful language to describe these persistent companions. I had the chance this past summer to hear what organic farmers think about weeds as I toured six organic farms in different parts of the country for a project I have been working on for Purdue and Ohio State universities.
At each farm, I asked the farmers how they’d describe their relationship with weeds. I got a few strange looks, quite a few laughs, and a word I had to look up after the interview. (Now I know what “peripatetic” means). Still, almost everyone noted something we all can learn from weeds.
“Actually, we do learn a lot from weeds,” said Dave Campbell of Lily Lake Organic Farm in Illinois. “It’s hard to believe just a matter of 40 acres away in another field, I’ll have different weed pressures than I will in another part of the farm. So I look at weeds and try to observe what kind of weeds I have, what the issue is, and why I’m having these weeds and try to address that issue.”
Peter Bane and Keith Johnson of Renaissance Farm also talked about the importance of observing weeds, but they talked about observing them in order to better understand their beneficial role in a farm’s ecosystem.
“Weeds’ function in the world is to cover bare ground and to restore the health of that ground by covering it, by diving deep into it and bringing nutrients up to the surface where other things can make use of them,” Keith explained. “Their job is part of the regeneration of damaged landscapes.”
Bob Cannard, an organic farmer in California, went beyond seeing weeds as beneficial, considering them essential on his farm.
“They’re my number one crop!” Bob said. “They’re the food that is going to allow the next cycle of crop to grow. The vegetable plants are a secondary response to a good soil and a good digestive system. A lot of people don’t like weeds. Well I love weeds, and it is all about managing the population densities and controlling the time/ space sharing between the different cropping systems.”
Each of these farmers saw weeds’ role on their farm in different ways, from indicators of problems to an integral component in a farm’s ecosystem. These perceptions drove how and when they decided to manage weeds.
Robbie Long of Earthbound Farms in California described his approach to managing weeds with one word: “cultivation.” He starts by pre-irrigating the beds a couple of times and cultivating shortly afterward to eliminate the first few flushes of weeds right after they germinate. Then, after the crop is planted and established, he’ll do a precision cultivation, leaving less than two inches either side of the plant uncultivated. A general weeding crew will go through and, while thinning the plants, they’ll hoe any weeds in the row. This is then followed by another cultivation and one last hoeing. Robbie is strict about not letting weeds go to seed in the field, and will actually have the weeding crew pack the weeds out of the field if they are going to seed. This labor can be expensive, ranging from $100 an acre for a fairly clean field all the way up to $1,000.
At Driftless Organics, farmer Noah Engel said the most important practice for managing weeds is field preparation. In fields with spring cover crops, he will turn under the cover crop, have a fallow period of a few weeks to allow a few flushes of weeds to germinate and then be cultivated. This approach doesn’t work in fields with spring-planted crops, where planting can’t wait until after the weeds germinate. In these fields, Noah includes a summer fallow in his rotation.
“Ideally we would have almost 50% of our land not in production every year,” Noah said. “That would be for soil building and weed control, doing the summer fallow, removing weeds with the field cultivator,” he explained. “We really try to do that—we’re a little tight on land.”
Summarizing Dave Campbell’s strategy for managing weeds would take several hours. Fortunately, he’ll have time to explain his process at the 2014 MOSES Organic Farming Conference, where he’ll present the workshop “Weed Management for Organic Field Crops.”
Dave starts thinking about how to manage weeds a year in advance when deciding his rotation, which type of crop to plant (food vs. feed grade), which varieties to use, which implements he’ll need ready, and how he can best manage his limited labor within those timeframes.
Bob Cannard’s weed management is a balancing act of letting the crop get established and then allowing weeds to assert themselves. He lets weeds complete their life cycle and then mows them with a flail mower before planting the crops. Once the crop is planted, he maintains a critical weed-free period by cultivating shallowly with a roto-tiller and wheel hoe, and occasionally mowing. Once the crop is established, he allows the weeds to grow, which provides several benefits. As he explained, the challenge to this strategy is that very delicate balance between the weeds and the crop.
“You have to pay attention,” Bob said. “You have to be intimately concerned and part of your farming operation. If you slack off, why the weeds are gonna take over and you’re gonna have plenty of soil food but not enough people food.”
Weeds are a constant challenge on farms, and no strategy will ever completely eradicate them from any farm, conventional or organic. Our challenge is to learn to understand these companions and find our own approach to controlling them on our farm.
Patrick Lillard is an Educational Program Specialist for Youth Development & Agricultural Education at Purdue University in Indiana. He is working on an organic weed management project, which includes a series of 10-minute videos profiling how six organic farmers manage weeds. The videos are linked at on the MOSES website here. The project also will include a webinar series on weed management that will be available later this year.
January | February 2014
Hear how Dave Campbell controls weeds on his organic crop farm.
Noah Engel, Driftless Organics, explains how he manages weeds on his 40-acre diversified vegetable farm.