Alfalfa stand establishment keys pest control
|By Hay and Forage Grower|
“While it is sometimes tempting to look only at quick solutions such as pesticides when confronted with a pest problem, it is well known that a range of agronomic practices have profound and important influences on the success of pest management,” said Dan Putnam, extension forage specialist at the University of California-Davis. He addressed the topic at the California Alfalfa & Forage Symposium in Reno, Nev., last month.
Putnam emphasized the concept of first evaluating your agronomic practices before focusing on chemical pest control measures. The most important of these “integrated crop management” practices include stand establishment technique, variety selection, harvest management practices, and irrigation decisions.
“Anything you can do to get dense, high-yielding plants with deep root systems will go a long way to resist weed, insect, and disease intrusion,” Putnam said. “In some cases, crop management may be the only alternative for pest management,” he added.
“In many respects, a package of proper stand establishment methods is the most potent weapon in the arsenal for growers fighting pests,” Putnam said.
Here are a few of Putnam’s must-do stand establishment practices to combat unwanted pest issues:
1. Pick a good site: Select your best fields or at the very least mitigate any shortcomings such as soil pH and fertility before seeding. Alfalfa, in spite of its many virtues, is particular about what it grows in. Do everything right and seed into a soil that has a low pH or lacks nutrient capacity, and stand establishment and performance will suffer. Pest pressure, on the other hand, may not.
2. Prepare the site: Eliminate any soil compaction for starters. Also, take steps to ensure that drainage is as good as it can be. In flood-irrigated situations, land leveling must be such to eliminate any ponding water, which encourages a host of root disease problems. Make sure the seedbed is firm so that seeding depth is more easily controlled. This helps ensure an early, dense stand that will compete against weeds.
3. Be on time: Every region has a recommended time frame for optimum alfalfa establishment. Late-summer or fall seedings are usually done long enough ahead of cold weather for the plant to develop a good root system. Check with your local extension office if you aren’t familiar with the optimum alfalfa seeding dates in your area. Again, strong, early stands discourage weed pressure.
4. Variety matters: “One of the most important decisions in managing pests in alfalfa is variety selection,” Putnam noted. Pick a variety with the right fall dormancy for your region and also take a close look at the variety’s pest resistance ratings for diseases, insects, and nematodes. Varietal pest resistance is often the only economically feasible defense against many alfalfa diseases.