Features Agronomy Other Crops
Getting with the program

Weeds, insects and disease can negatively affect a potato crop and most growers develop strategies to manage these yield and quality reducers. But some growers find managing all the variables a bit daunting and will call on crop consultants to help them through the maze of products, application options and timing. In Manitoba, where aerial application, ground application and pivot irrigation all have a place in production, knowing when to spray, what to spray and how to spray can have an important impact on the success of any operation.

Scouting is the key to making pest management systems work. Photo Courtesy Of Bernie Zebarth, Agriculture and Agri-Food Canada.

“We try to help growers make decisions,” says Trevor Thornton of Crop Care Consulting near Carberry. “We scout fields to ensure growers don’t waste their money.” He adds that each pest requires its own solution and application timing can be critical. For late blight, he explains, growers need to spray before there is a need, but for Colorado potato beetle, growers can spray at threshold and not as a preventive action.

Another crop consultant from the Winkler area says in his 12 years of working with potato crops, he has learned that most growers like to have solutions that are simple and easy to
follow. “They still like to have advice on how to approach a problem,” explains Kurt Ginter of KR Crop Check. “We try to develop a weekly program for them so they know what they need to do each week and on which day and what operation is required. We will choose the products and the rate they need to apply depending on the disease pressure and we try to start the program based on the size of the plants. Ideally, we like to have one or two applications of fungicide on before the plants are large enough to touch each other.”

Having a strategy to manage disease and pest pressure helps growers succeed. Both Thornton and Ginter also assist their clients to manage products to reduce the chance of resistance developing. “We work towards resistance management with all our growers and we will recommend natural controls, such as tillage, as well,” says Thornton. “We don’t want to lose our potato products, so we also try to assist our growers to manage weeds in the crop prior to potatoes, which keeps the products registered for potatoes and available to use with reduced chances of developing resistance.”

“Of course, we try to help our growers manage resistance,” says Ginter. “For Colorado potato beetle, we recommend either in-furrow or seed piece treatments. Growers who don’t want to use these products seem to have more problems because they don’t have enough products to rotate to for control.” Some experts recommend spraying borders around the field early in the season to prevent beetles from getting into the middle of the field. In theory, this practice is to reduce the amount of product needed and is designed to control beetles. But the success of this strategy is mixed.

Thornton and Ginter agree scouting is the key to making this system work, but Ginter says he has found that not all growers will embrace it. He reports that if the control is not applied at the proper time or a substituted product is used, the beetles will still enter the field and then a second application is required which may overlap the border spray, causing crop damage and encouraging resistance. He says most of his growers prefer to spray the entire field once and feel comfortable they have control, but they will only take that step if Ginter recommends it. For Thornton, the border spray strategy is sometimes successful, but “it all comes down to scouting.”

Ginter says his company offers a complete agronomy program of which pesticide spray programs are only one component. “Our program involves fertility, field scouting, field management, variety selection and we will even help our growers decide which fields to plant,” he says. “We keep a field history for them and, sometimes, we can manage problems the year before potatoes are planted. If we know a field has had a history of disease, pest or weed problems with one crop, we might suggest that potatoes not be put in that field because the available control options are fewer with potatoes.”

Thornton offers similar services. “We help our growers manage their crop and improve the bottom line,” he says. “We ask growers to scout their own fields as well because I think we work best as a team. It is important for growers to put their own shadow on their fields.”
“We custom tailor our services to meet the needs of our customers,” explains Ginter. “Some growers want our expertise and some just want advice. Because we only sell service and not products, we recommend only what a grower needs with an unbiased approach. That’s the best strategy,” he adds.

Thornton says he likes growers who are open to new ideas and strategies. “It’s so important to manage resources to maximize profitability,” he says. “I think there are opportunities to incorporate some of the ideas from organic or biological agriculture that could benefit modern agricultural management.”

Planning strategies for pest and disease management can be easier with the help of a crop consultant. Often it is not just about spray strategies, but how the product is being sprayed and what is being sprayed fit into the overall crop production picture. It may be worthwhile to consider using other management tools at the recommendation of a crop consultant because, as most experts agree, the more growers are able to keep pests and disease controlled using a mixture of alternate and traditional methods, the more likely the industry will be able to preserve the tools at the growers’ disposal for a longer period of time. -end-