A functional feedlot
Compost from cattle manure has found a home in Alberta potato production.
Southern Alberta is well known as cattle country, but the region also is home to significant commercial potato production. Now, a partnership between a potato grower and cattle producer has proven to be a fortuitous – albeit rather unorthodox – opportunity to unite the two industries for mutual benefit.
Harold and Chris Perry are co-owners of the Kasko Cattle Company, with feedlot owner Ryan Kasko, on 10 quarter-sections of land surrounding the Kasko Cattle Company feedlot east of Taber, Alta. Kasko owns and operates the feedlot itself, which raises about 14,000 head of cattle annually. Harold Perry says they partnered with Kasko in the recent purchase of the land surrounding the feedlot partially because it provided them with a ready supply of manure that they could convert to compost for use in their potato production.
The potato producer benefits primarily from the nutrient and micronutrient value delivered by the feedlot’s manure when it is applied on potato cropland in the form of compost, while the feedlot has a handy place to dispose of its significant accumulation of manure right nearby. The feedlot owner delivers the raw manure to a dedicated composting site with good drainage control where the potato producer converts it to compost. It is land applied in October and worked in before the potato hills are created for next year’s planting.
The Perry family’s expertise, which includes Harold and Chris’ father, Gerald, is in producing crops such as potatoes, sunflowers and peas on a total of 4,600 owned and rented acres. Their business is headquartered close to the town of Chin, about 40 kilometres from the feedlot – a typically hot, dry climate requiring irrigation, with plenty of frost-free days. The Perrys have a contract to produce 13,500 tonnes of potatoes for Frito Lay and 8,500 tonnes of potatoes for McCain Foods on about 1,300 acres that are under irrigation for that purpose.
For the past decade, the Perrys have used cattle manure compost as fertilizer in their potato-growing operation because of the nutrient and microbial benefits they’ve realized from using it. Harold Perry says they observed with growing potatoes on virgin potato growing soil versus soil that had been under cultivation previously in a four-year potato crop rotation that there was a dropoff in potato production on soil where potatoes had been grown in the past. They discovered that using compost on the potato rotation land not only provided organic fertilizer to the crop but also worked as an excellent soil amendment, adding many micronutrient and biological unknowns to the overall quality of potato-growing land that really made a difference in commercial potato production.
“We wanted to try compost because that is the natural way that things work,” says Perry. “When the buffalo were here, they ate and manured the grass at the same time, and that’s how the natural cycle worked. Fertilizer prices have also helped because compost makes sense if you go strictly by dollars. The cost of putting the amount of nutrients you put on your soil using compost is less than if you were to purchase that at a fertilizer dealership.”
Composting the manure deals with that issue, and it is also more economical to transport nutrients in this form than as raw manure. The Perrys can attest to that fact.
“Good compost has about 60 per cent of the weight of raw manure,” says Perry. “So if you get too far away from the feedlot, then the trucking just kills you.”
Research being conducted by Agriculture and Agri-Food Canada, specifically in Summerland, B.C., also is showing that the addition of compost could help in the prevention of verticillium wilt, also known as early dying syndrome.
Potato crops infected with this pathogen will typically see the tops of potato plants die off between early August and September, which can have a devastating impact on potato production in the case of a bad outbreak. The pathogen enters the plant through root lesions. The root lesions are caused by nematodes that live in the soil and feed on the roots.
So far, what the B.C. research has shown is that the addition of compost enhances the presence of a fungus that feeds on the nematodes, thus reducing the amount of root lesions and closing the pathway for the verticillium wilt pathogen to enter the plant. Results so far have been promising, although the theory hasn’t quite been proven yet, according to Dr. Frank Larney, research scientist in the area of soil conservation with Agriculture and Agri-Food Canada (AAFC) at the Lethbridge Research Centre in Alberta.
Before the Perrys became partners in the feedlot, they were purchasing their compost from a commercial supplier. It was partially because of compost quality issues that they agreed to invest in land surrounding the Taber area feedlot with Ryan Kasko so they could acquire their own supply of raw cattle manure to manufacture compost. The Taber feedlot and surrounding land were also near their potato growing operations, so all the pieces conveniently fell into place.
Harold Perry is in charge of compost production. “If I have a goal, it’s to have healthier soils, for healthier crops, for a healthier population,” he says.
The Perrys pay Kasko for the cattle manure, and he in turn hires a custom contractor to deliver the raw manure to the compost production site. The custom manure hauler creates the windrows needed to produce compost. During the first year of compost production, the feedlot delivered about 9,000 tonnes of manure to the site. Delivery of the manure resulted in four windrows measuring a distance of about half a kilometre each.
Once the windrows were created, Perry began monitoring the conversion process and used his compost-turning equipment as needed. He acknowledges feeling a bit anxious about delving into compost production because of the science required to ensure that the biological organisms have a healthy environment to carry out the conversion process but adds that learning to compost has been an enjoyable experience. To prepare himself, he took a composting course offered by Midwest BioSystems. The conversion process takes from July to mid-October.
To turn the compost, Perry purchased a 14-foot wide, pull-type, Sittler compost turner, which retails for about $45,000. He was able to recoup about half the cost by applying to a government program called the Growing Forward Manure Management Program. He checked the heat and moisture content in the composting windrows regularly to ensure that the organisms were working in an optimum environment. He also purchased a Sittler water wagon that can be towed along with the compost turner so that moisture can be applied to the windrows as needed. Perry says he turned the compost six or seven times with the main determining factor being when the temperature in the compost heap reached 160 F. At the beginning, the turning was done every four or five days because of the strong biological activity underway. Ideally, the conversion process should take 10 weeks, but Perry says he prefers to wait 16 to 20 weeks.
As part of the Perrys’ adventure into composting, they hired an agriculture consultant from Sunrise Ag in Taber to soil sample and develop topography maps to help determine how much compost should be applied at various points on their cropland. The consultant developed maps showing six zones where the compost should be applied to a lesser or greater extent to achieve ideal growing potential.
To spread the compost, Perry purchased a Bunning compost spreader with vertical beaters, which he pulls using a John Deere 8430 tractor equipped with hydrostatic drive. Perry recommends a tractor in the 180- to 200-horsepower range. The tractor moves at about 16 kilometres per hour, and the spreader broadcasts the compost over a width of about 40 feet. This results in an application rate of about four tonnes per acre. Increasing or decreasing tractor speed based upon the zone mapping displayed in the cab will increase or decrease the application rate.
Larney says he is not surprised by the results witnessed by the Perrys. He says using compost in the lighter, sandier soils under irrigation in southern Alberta delivers “a better bang for your buck” than perhaps it would in the soils where seed potatoes are grown in central Alberta. These soils typically contain more organic material. Given the amount of row crop type production in southern Alberta and because these crops do not return organic matter to the soil, Larney says, “the addition of compost is a very good way of replenishing soil organic matter . . . it’s the quickest way.”
He adds that compost also delivers other benefits, such as the addition of micronutrients not present in commercial fertilizer, and also improves the soil’s water holding capacity, making it more resilient to both wind and water erosion.
Given how close together both cattle and potato production are in southern Alberta, he says their co-operation is a natural fit.
“It kind of makes sense that it (manure) should end up on potato land,” says Larney. He is noticing more feedlot operators moving in the direction of composting the manure in advance versus simply land applying raw manure.
“I think a lot of feedlots are now realizing that they should look at composting because you can only rely on your neighbours for so long to take raw manure,” he says. “With the buildup of phosphorus levels in particular close to feedlots, I think the onus is on the feedlot owners to hopefully ensure that these nutrients are spread out over a wider area so that we are not getting high nutrient loading on land close to the feedlot.”