BURLEY — Next fall’s harvest success is determined by how carefully growers pay attention to a few key practices before planting.
“You must have good practices to get good results,” said Juliet Marshall, University of Idaho Extension cereal pathologist. She also runs the UI variety trials across the state.
Success starts with variety selection. While choosing a variety with resistance to known pests on your farm is critical, Marshall says knowing your market is just as important.
Irrigated winter barley varieties, for example, used to be primarily used for feed but the emphasis is switching to human food purposes. Some of the newer varieties may have higher test weights but are also more susceptible to lodging. Not only is lodged grain harder to harvest, but grain heads lying on or near the ground are susceptible to fusarium head blight.
New malt types are being introduced to the area from Canada and Europe, but not all have the characteristics American maltsters are looking for. Marshall cautions growers to verify that a variety has met the American Malting Barley Association’s standards or have a bona fide market before jumping on a new variety.
“Make sure any new variety from out of the area has been tested here (in a variety trial) so you know the agronomic characteristics, like lodging,” Marshall told grain growers during the annual UI MiniCassia cereal school held this month. “Base your management decisions on multiple years and multiple locations for variety selection.”
She also recommends growers start each season with a soil test. Growers often focus on nitrogen, which is critical for meeting protein requirements in hard wheats, but overlook other key nutrients. Sulfur, for example, is key to plant health and many quality standards. Potassium is essential for building straw strength and reducing lodging potential.
“Know your soil fertility and manage for overall plant health and maximum economic yield,” Marshall said. “You want your plants up early to maximize sunlight exposure and build stronger plants.”
Climate change is starting to show up in Marshall’s long-term variety trial data. Heading dates reflect planting dates — the earlier the crop is seeded, the earlier the plant heads out. That earlier maturity, in turn, impacts irrigation water management.
On average, the winter wheat varieties in the 2018 UI trials headed three days earlier than the 10-year average. The spring varieties were a whopping eight days ahead of average. Growers need to take these trends into account when seeding grain to reduce potential for certain diseases or manage crop rotations.
Marshall has been encouraged to increase the seeding rates used in the UI variety trials to increase yield. She seeds at the rate of 1 million seeds per acre but did some tests last year seeding a hard white wheat variety at 1 million, 1.2 million and 1.4 million seeds per acre. Statistically, she would need to harvest 9 bu per acre more wheat in the fall to justify the cost of using more seed and increasing other inputs proportionally. Harvest data showed 119.5, 119.2 and 125 bu/ac respectively.
She admits that the fields with the higher seeding rates looked visually better, but a 5 bu/ac difference isn’t enough to offset the higher input costs.
“Statistics are for a reason,”Marshall said. “If someone tells you he got a five bushel increase that’s great but it’s not statistically different.”
Overseeding can also lead to taller, thinner, weaker plants that are mores susceptible to lodging.