Stacking tools for better weed control

EL PASO, Ill. — Hans Bishop’s move into effective organic row crop production weed control begins with his experiences in growing vegetables on his family’s PrairiErth Farm near Atlanta in central Illinois.

Bishop shared those weed management experiences during a recent workshop hosted by Organic Agronomy Training Service and Krug Family Farms.

“My hoeing tool story would not be complete without touching a little bit on my experience with vegetables. We were scaling up that operation, and we were looking for ways to decrease labor because that is like 42% of your expenditures on a vegetable farm, probably more now,” Bishop said.

“There just wasn’t anything available in the United States 10 years ago, so we looked outside the United States. The reason Europe has so many of these tools is there’s a lot more restrictions on chemical usage in the EU.

“A lot of the things that are available now in the United States are derived from what European manufacturers have come up with.”

One of PrairiErth’s main crops was fall storage carrots, a vegetable with very small seeds that doesn’t compete well with weeds and requires a lot of hand-weeding and labor.

Bishop was able to find tillage tools from Europe that could get within three-fourths of an inch on either side of the carrot plants. Many of those same tools were then being used in row crops.

“2020 was my first year of growing organic row crops. I had an opportunity in 2018 to give a presentation at Practical Farmers of Iowa with Leonard Mol who was the engineer for Steketee, which is now part of Lemken. A lot of the information I have is from Leonard,” Bishop said.

“In Europe, they talk more about hoeing machines than cultivators. They actually look at hoeing a field versus cultivating because hoeing is more precise as opposed to just dragging sweeps through a field and hoping you uproot some weeds.”

Leonard found that commercial cultivators were leaving a portion of the field beyond just the cash crop undisturbed, opening the door for more weed pressure.

“A lot of old-school spring trip shanks that you see from International, John Deere, etcetera, are meant to uproot and not necessarily cut. Sometimes they vary from working correctly, but not every time you bury a weed is it going to die. It depends on how much energy it has stored,” Bishop said.

“The point is, if you’re not disturbing the soil over the whole field, then you’re going to have greater weed populations.

“Our International cultivator covers between 19 and 20 inches width in between the rows. So, every time we make a pass, we’re leaving 34% of the field undisturbed, which over an 80- or 100-acre field that adds up pretty quickly.

“What Leonard came up with is the sweet spot is in the 12% to 20% range. So, tightening up either your planting systems or your cultivation tools will help with decreasing your weeds in the field after you planted.”

Stacking Tools

In working primarily on vegetable production weed management trials with a University of Maine research team in Michigan, Bishop said they began stacking cultivation tools, a system that that crosses over into row crops.

“The more soil disturbance you can do or different types of disturbance you can do in your pass over the field, the more effective you weed control is going to be,” he said.

“So, maybe there’s even a gap in your sweeps that are set up on your old International cultivator and in your first pass you might even leave two strips of weeds in between your row sweeps and your middle sweep.

“If you have a stacked tool behind that like a finger-weeder, a wire weeder, or something like that, that will increase the effectiveness of that.

“What we really like in the Steketee Lemken components are its ease of adjustability. All of them have a crank, and International has been defunct for about 30 years now so there’s probably going to be a little bit of rust on those bolts and parts. With these parts, everything moves easily and is easier to adjust more precisely.”

There are many different components that can be added to a cultivator. Bishop added rolling shields to their Steketee cultivator this year.

“That was mainly because we were working in a high residue situation. We need to make a early cultivation pass before it actually decomposed, so we were trying to keep giant balls of residue from rolling into the row and covering up our newly emerged corn plants,” he said.

“You have the shield, the working sweeps and then finger-weeders. So, there’s three different components you can add on to each element to increase its effectiveness and really dial it in to your crop needs.

“They also have varying types of ways you can mount your sweeps, whether that’s on spring shanks that vibrate and do more shattering of the soil off of the roots of the weeds.”

Blades

An A blade and a L blade are among the other optional components, with the A blade similar to spring trip shanks on a standard corn and soybean cultivator.

“We use an L blade a lot in carrots, but we’ve found it very effective when moving over to early cultivation in soybeans because there’s companion blades that would be on the right side of your row and that shields the soil from flowing into the row,” Bishop said.

“You pair it with something like a cut-away disc and that gives you a trench right next to the row that allows soil to fall back into the trench and work a lot close to the row of crop. This would be for early cultivations.

“Whether it’s the A blade or the finger-weeder, all of these have the same standard so you can plug these different tools into different ports on your elements when you adopt a consistent hoeing system.”

A rake type tool is another option that would be installed in the back that helps shatter the soil off of the roots of weeds.

“It’s paired with rolling shields that also help do cutting. Some of the styles of shields you can tilt so they do act kind of like a cut-away disc. It just depends on your budget to what your need is,” Bishop said.

Finger-Weeders

Finger-weeders are intended to increase the amount of soil that’s being disturbed. It’s effectiveness can be decreased if the ground is hard from hard-pounding spring rains.

“Sometimes that will decrease the effectiveness of the finger weeder because the fingers don’t penetrate through the soil quite as well when there’s crust. But there’s also different firmness of fingers you can get based on your soil types. They even have a brush you can put on there for saving soils where the soil is easily disturbed,” Bishop said.

“For example, you have 5 inches of space between your cultivator sweeps, and then you include finger-weeders, you’re actually going to be increasing that amount of soil disturbed when you throw your finger-weeders in that will increase the amount of soil per acre.

“We tried brushes on vegetables and they didn’t work for our soil type, but this just demonstrates the versatility and options that there are for your specific needs.

“We’ve always had our finger-weeders mounted for vegetables and row crops on independent spring arms. The finger-weeders are working after the row units have gone through the soil so they disturb the 26 inches in between your 36-inch rows.

“You can independently adjust the aggressiveness of your fingers. You can put them close together. You can overlap them. All of those different settings change what kind of soil action you get through the field.

“If conditions aren’t right for them, you can put the finger-weeders in the transport position. You don’t have to run them, and just run the cultivator in between the rows.”

Other options include roto weeders. It has a similar action to a tined weeder that’s ground-driven. It’s run between sweeps or just ahead of the finger-weeders.

“This all builds on the idea of stacking tools, where the more things you’ve got to go into the soil, the more weeds you’re going to throw out,” Bishop said.

In addition, there is technology that combines cameras and GPS. The cameras identify the row crop and lifts or inserts the cultivation tool into the ground so as not to damage the crop itself.