Strawberry Hill Farm, Pembroke, New Brunswick
Tim and Kirsten Livignstone bought Strawberry Hill Farm in the St. John River Valley of New Brunswick in 2011, and have just completed their 10th season of production. The diversified organic farm produces 50 crops along with beef, pork, chicken, and pasture-raised eggs. Eight seasonal staff and four year-round employees were employed last season to work on the 250 acres of total farmed land, which includes about 15 acres in vegetables, 30-40 acres in grains, and the remaining acres in pasture and hay.
Soybeans and grain for livestock feed are produced on the farm, with the grain grown in rotation with hay fields. Products are sold through a CSA and online ordering on the farm’s website.
Before operating Strawberry Hill Farm, Tim and his spouse ran a soil biology lab, consulting and selling products to farmers. When they bought the farm, they looked forward to trying new approaches while keeping the farm entirely organic, and applying their background in soil biology.
Challenging weeds
“By far and away,” Tim said, “the worst economic weed is hairy galinsoga, on vegetable land. Pasture, probably Canada thistle. I’m working on ways to train the cattle to eat it. Apparently, it can be done.”
Hairy galinsoga (Galinsoga ciliata) first appeared at the farm in 2016, and has since been a major challenge in certain vegetable fields. “It doesn’t take very much population [of hairy galinsoga] to make it yield-limiting”, Tim said. The weed has been especially problematic in fall carrots and beets, seeded in mid-to-late June or later. Basket weeders have been effective in handling hairy galinsoga between crop rows, but they leave behind a 2-inch undisturbed strip of crop row. “If there’s just a few galinsoga plants that come up in that 2-inch strip,” Tim said, “it will drown out the crop. It’s a very tough weed to remove from the plant row, because it spreads and branches out everywhere, so when you pull it, it wants to take other stuff with it.”
Common lambsquarter (Chenopodium album) has also been an issue in grains and sweet corn, but thus far, Tim has found it easier to deal with than most other problem weeds. Pre-emergence flame-weeding or cultivation when the weed is at the white-thread stage have both been effective in managing common lambsquarter populations in vegetable production, Tim observed.
Weed management at Strawberry Hill Farm
Tim and the crew at Strawberry Hill Farm use physical weed control, seedbank management practices including flame-weeding, crop rotations, and stale seedbedding, and mulching with both straw and plastic in their weed management strategy.
To create stale seedbeds, Tim will wait for a flush of weeds to emerge in a prepared bed before planting, then till to a depth of about one inch to kill weeds germinating in the shallow top layer of soil. If there is time, some beds may be skim tilled twice before planting.
After the crop has emerged, basket weeders, S-Tines, Danish sweeps, and Lely tines are used for cultivation, depending on the crop. Given their scale and diversity of crops, Tim typically switches cultivation systems on a weekly basis, running through all cultivation events that require one particular equipment set-up then going through all the crops requiring new set-up. Cultivation is usually performed every 7-10 days. 14 days intervals are typically too long but may work in some cases. Most tools are set to the required adjustments ahead of time to be ready to go for cultivation, with the exception of readjusting certain detachable tractor-mounted tools.
Evaluation of stacked tools
The finger weeders Tim tried in soybeans were not as effective as their own equipment (Danish sweeps) at the time they experimented with the tool. “The finger weeder was slow, and did not give us any better control than what we already had,” Tim said. “That said, I also was learning how to use the finger weeder, and you can use it sooner [in the crop’s growth period] than my equipment, and I did not try that. So I really did not feel like I fully learned the tool. Later in the year I played with it with green and yellow beans and corn, and there’s a lot of potential there. I’d like to work with it another season. I think it’s a really good tool to have in the toolbox.”
Reflections from the on-farm research project
“I want to improve or trial more systems for stacking, because I’ve seen that stacking is better than each individual tool”, Tim said. In addition, Tim would like to spend more time testing finger weeders in soybeans when the crop is at an earlier growth stage.
Further information, tools, or resources
Tim would like to see more data on how different cultivation equipment affects crop damage, yield, and weed counts. Having more opportunities to test tools in the field conditions they will be used in would also be helpful, he noted. Reflecting on past tool demonstrations at other farms or, in one case, at a conference, Tim said, “A tool can look really good and seem really good, but. . . different soil conditions can make a tool very quickly not perform.”
Figure 1: Mental model of the components and connections within the weed management system at Strawberry Hill Farm.
Key:
- Gray boxes represent farming system priorities, orange boxes represent overall weed management strategies and goals, blue boxes represent physical weed control practices and decision-making, and purple boxes represent key lessons on using physical weed control tools based on practical experience.
- Blue arrows indicate the five strongest perceived relationships between components within the mental model. The orange arrow indicates a strong negative relationship.