Harvest management for winter wheat
By Donna Fleury
By Donna Fleury
Winter wheat is an important crop for many producers across the Prairies. Planning ahead is necessary, particularly for harvest management. Producers planning to seed winter wheat in the fall of 2011 should have their plans in place the spring before. “Producers have to start planning early and start thinking about crop rotations and the stubble they plan to seed winter wheat into,” says Janine Paly, winter wheat agronomist with Ducks Unlimited Canada, in Alberta. “Producers will get the most consistent results by direct seeding into standing stubble, preferably tall and dense to catch more snow and protect the crop better over winter.”
Growers should select the field that they are planning to seed to winter wheat the spring before, then plan to seed as early as possible in the spring so it will be harvested early enough for fall seeding. “Canola is one of the best options, while oat and barley silage stubble is a great alternative and provides similar yield results to canola,” says Ken Gross, provincial agrologist with Ducks Unlimited Canada, in Manitoba. “Flax is also an excellent choice if you can get it harvested early enough.”
Paly adds that, in situations when these options are not available, pea stubble can work in certain parts of the Prairies and seeding into forages is also an option.
“The recommended stubble height for canola is a height of 12 inches or 30 centimetres,” says Gross. “If seeding into flax or previous cereals, then eight-inch height is sufficient. If forages are used, then we recommend leaving at least six inches of standing stubble, although eight inches is better for trapping snow.”
“One important practice when producers are harvesting their spring seeded crops, is spreading chaff and straw evenly and avoiding excess traffic to maintain the standing stubble,” explains Paly. “Producers should also avoid harrowing prior to seeding winter wheat, because it will break down the standing stubble.”
Kendall Heise farms about 3000 acres at Isabella, Manitoba, near Hamiota. He tries to seed at least 300 acres of winter wheat every year, and in some years has seeded as much as 600 acres. “If I could grow more I would, but having enough stubble ready early enough in the fall and the difficulty of managing around the rest of the harvest operation can be a challenge,” he says. “We prefer to seed into canola stubble, although we have seeded into several other crops.”
Heise prefers to leave the canola stubble as tall as possible to minimize the straw going through the combine. He uses a Seed Hawk for seeding and can usually manage the taller stubble. “It’s important to have a good understanding of your own seeding equipment and how much residue you can comfortably seed into,” says Heise. “You don’t want to be surprised when you are out in the field with a tank full of seed.”
He has also noticed that with the increased use of fungicides, the application can leave tracks through the stubble and push the crop down. “The sprayer tire tracks can also cause problems for swathers, which don’t cut the stubble very well and exaggerate the problems when seeding winter wheat. Seeding crossways to the sprayer tracks can help.”
Paul Schoorlemmer farms 3500 acres at Rycroft, Alberta, and usually grows about 500 acres of winter wheat every year. Unlike much of the Prairies in 2010 that were quite wet, the Peace region suffered drought conditions and most areas were quite dry during the growing season. “Although canola stubble is our preferred choice to seed winter wheat into, being this far north we have a hard time consistently getting the canola off early enough. Therefore, we find we are seeding winter wheat into pea stubble more often, although pea stubble is not ideal as we would like to have more stubble standing to catch more snow.”
Winter wheat handles moisture very well and is very moisture use efficient,” says Gross. “Once winter wheat is seeded, it seems to be able to handle wet or dry conditions, which is a big benefit for growing the crop.” Heise adds that in a very wet year like 2010, winter wheat withstood the excess moisture conditions much better than spring-seeded crops because it was bigger and able to handle it. “So going into this winter very wet, I’m glad I got winter wheat seeded again this year.”
Schoorlemmer and Heise both advise growers to plan ahead, get everything ready in the summer, have the seed and equipment ready to go, and be ready to go at a drop of a hat. “You can’t wait to set everything up during the
Heise adds that having a truck available for delivering seed to the drill and enough manpower for all the jobs is also a challenge.
For Schoorlemmer, the biggest challenge is trying to do everything at the same time at harvest. “Trying to get the old crop off and the new crop seeded by the target dates is a challenge. Being a little further north, our seasons are a bit more compressed than some other areas further south, and in some years the winter wheat and spring wheat harvest are almost at the same time. We really grow winter wheat more to spread out our risk than the workload.”
Weed and disease management
Producers have various options for weed control with winter wheat, including preseeding, fall in-crop and spring in-crop, depending on the types of weeds being controlled. “We’re starting to see more winter annual weeds such as stinkweed and flixweed that are very competitive with winter wheat,” says Gross. Fall is the best time to scout for and control winter annuals, and using Buctril M at the two- to four-leaf stage is recommended. “In areas where wheat streak mosaic virus (WSMV) is a problem, it is important to control grassy weeds and cereal volunteers either with a preharvest herbicide, especially if seeding winter wheat into a cereal stubble, or preseed burnoff prior to seeding winter wheat,” explains Gross.
“The field should be free from green material for at least 10 to 14 days to break that disease cycle,” adds Paly.
The WSMV is spread by the wheat curl mite (Aceria tosichella), which transmits the virus from diseased to healthy plants. The mites require living plants or a “green bridge” to survive, and usually overwinter on winter wheat crops. “It is also important to do a fall application after winter wheat harvest to control any winter wheat volunteers that could spread WSMV,” says Gross. “You can’t do anything about it when it is in your crop.”
Glyphosate is an inexpensive treatment and helps producers set up their fields for the following spring. Although there are some WSMV winter wheat varieties under development, Radiant is the only variety with resistance to the wheat curl mite and grows well in Alberta although not as well in Manitoba.
“We try to select fields that that aren’t especially weedy for seeding winter wheat and spray glyphosate either before or after seeding,” says Heise. “I wouldn’t recommend spraying after seeding because if there are a lot of weeds, the seeding operation can cover up smaller weeds with residue and then you do not get very good coverage
Heise is concerned about WSMV and tries to choose fields that do not have any volunteer wheat.
For winter wheat, Schoorlemmer either uses a preseed or pre-emergence glyphosate application, depending on whether the crop before was desiccated and if there are any weeds growing. “We usually do an in-crop application in the spring, normally a broadleaf control on all of the acres and typically a wild oat control on about one-third of our acres,” says Schoorlemmer. “It depends on the year and the field, and sometimes if a stand is a bit more patchy, we have to be more concerned about wild oats. We check every field and make a decision at that time whether or not the wild oat control is required.”
So far WSMV is not a problem in the Peace region.
Heise does rely on fungicide applications for leaf diseases. “Winter wheat is a crop that definitely needs some leaf disease control and sometimes Fusarium as well, especially for the eastern side of the Prairies,” says Heise. “The available varieties have very little leaf disease resistance built into them. Fertility is also important, especially if you are planning to use fungicides. Winter wheat has the potential to yield very well, so it is important to use an adequate fertility package in order to maximize the yields.”
Heise adds that producers need to be cautious when selecting varieties, because the Canadian Wheat Board has narrowed the list of varieties accepted for the CWRW grade class. “Some of the more commonly grown varieties did not make the cut, so make sure you know which ones are on the list. Although you can grow the rest of the varieties, they will likely go into the feed or ethanol market.”
“We have a strong relationship with Bayer CropScience, which is funding our program initiatives including critical winter wheat breeding efforts,” says Gross. “In addition, we just signed a federal agreement in partnership with the provincial winter wheat commissions worth more than a million dollars that organizes agronomy research across the Prairies. The Bayer funding was very helpful in leveraging these dollars that address agronomic crop management issues and plant health.”