May 21, 2013
Babysitting season begins for young canola. In the first three weeks after emergence, each canola field deserves an hour or more of close scouting per week.
“It may seem like a big commitment, but this time pays off quickly if it means stopping flea beetles that have reached economic levels of damage, or making a better decision on herbicide tank mixes and rates to get weeds that are bigger or more plentiful than expected,” says Keith Gabert, Canola Council of Canada agronomy specialist. “There’s an old expression that the most important input in a field is your shadow, and that’s true.”
Scouting can be squeezed in when weather conditions — such as wind — make spraying impossible. Growers can also use an agronomist to support their own scouting program.
“Company or private agronomists often have a regional view of pests and issues and they likely get the opportunity to track similar problems across a number of fields in your area,” Gabert says. “They can also provide experience and skills to help growers make informed decisions about weed, disease or insect control, stand establishment issues, or reseeding after a frost.”
Seedling and early rosette stages are critical times for canola. Plants are tiny and vulnerable and need regular scouting to make sure they’re protected. “In fields where plant counts are below 7 per square foot, it’s extra important to protect those plants to maintain the crop’s yield potential,” Gabert says.
What you might look for at this point in the season:
Seeding issues. This is the perfect time to check that the seeding job measured up to expectations, and if seeding equipment met your needs. Look for emergence patterns that may indicate an issue with depth control, leveling, compaction, packing or speed that can be adjusted for next year. “If you adjusted something within your program — such as tried a new blend or type of fertilizer, or had an “oops” with unexpected input rates — take a look at these areas to see if they might teach you something important,” Gabert says.
Plant Stand. Record the plants per square foot at various locations to see how well canola established with your combination of variety, seeding rate, equipment and moisture. Keep this information along with seeding rate, rainfall before and after seeding, soil temperature at seeding, and general soil conditions (lumpy, mellow, etc.). This data will help establish and understand your seedling survival rate.
Frost damage. When canola fields get an early season frost, wait at least 4 days after the frost even to assess regrowth before making any decision regarding reseeding.
Weeds. Pre-seed and/or early in-crop are the most economic times to spray for weeds. This gets weeds when they’re small and easier to control, and before they can take up moisture and nutrients you want for the crop.
Flea beetles. Canola is at risk up to the 4-leaf stage. If flea beetles are overwhelming the seed treatment, then consider a spray if 25% of leaf area has been eaten and flea beetles are still actively feeding on the crop. Examine newer leaves for recent damage. Canola seed treatments require a bit of feeding to stop flea beetles, so older leaves may be damaged for this reason while newer leaves may be undamaged.
Cutworms. Look for bare patches and dig around the perimeter of the patch to look for cutworms just below the soil surface. A number of insecticide options exist for cutworm control. However, if scouting determines that wireworms or gophers are the problem, the sprayer will not work on either of those pests.
Seedling diseases. Stem damage near or below the soil surface is likely seedling disease. Nothing can be done to stop seedling damage, but identifying the problem can help with planning for next year. For example, seedling diseases can be more common in canola seeded too deep into cool and wet soils.
“These are some of many issues worth scouting at seedling and rosette stages. Keep an open mind to any possible cause. It may take some extra sleuthing to find the answer, but knowing the answer will make sure you take the right action,” Gabert says. “The new Canola Diagnostic Tool at www.canoladiagnostictool.ca can help you work through all possible scenarios.”
After three weeks, canola plants are usually well established, competitive and can sustain more damage. A canola crop is never free from threats and scouting should continue all season long, but the weekly attention is critical this time of year.
Sign up for the free Canola Watch newsletter at www.canolawatch.org and follow @CanolaWatch on Twitter. For more on hiring an agronomist, enter this link for a full Canola Watch article: http://www.canolawatch.org/2012/12/05/do-you-have-the-time-ing/
For more information, media can contact Canola Council of Canada agronomy specialist Keith Gabert or a CCC agronomy specialist in your region:
Keith Gabert, Central Alberta South
Kristen Phillips, Manitoba
Shawn Senko, Eastern Saskatchewan
Clint Jurke, Western Saskatchewan
Autumn Holmes-Saltzman, Southern Alberta,
Dan Orchard, Central Alberta North
Greg Sekulic, Peace Region of Alberta and B.C.,
This media release is supported regionally by:
Alberta Canola Producers Commission; SaskCanola; Manitoba Canola Growers Association; Canola Council of Canada; Peace River Agriculture Development Fund; B.C. Ministry of Agriculture & Lands.