Drain tile, new weed threat discussed at Northern Corn and Soy Expo

Mikkel Pates
Forum News Service

FARGO — A hearty crowd of more than 500 people attended the second annual Northern Corn and Soy Expo and trade show at the Fargodome on Feb. 12.

Organizers said attendance felt the effects of slippery rural road conditions. Nancy Johnson, executive director of the North Dakota Soybean Growers Association, said more than 700 had pre-registered for the event that combined forces for the two crops.

The event for the first time featured Joe Ikley, North Dakota State University Extension Service’s new weed specialist, offering an update about Palmer amaranth weeds.

Palmer plants can produce 1 million seeds per plant, Ikley said. It is now in about 40 states and in 2018 was found in five North Dakota counties.

He said farmers must learn to identify weeds to win the fight against Palmer amaranth The seeds are very small — the size of pepper — and can be spread through livestock feed, equipment and contaminated seed sources.

Ikley, who came to NDSU on Dec. 31, recently received his doctorate from Purdue University. He says the biggest issue in Palmer amaranth control is proper identification. “Once it gets over 4 inches, most herbicide bets are off and it produces a lot of seed,” he said.

Three-year cycle

Farmers usually experience a three-year awakening as they realize the weed has hit, he said. In the first year, producers don’t think they have it. The second year, they see a “few escaped pigweeds,” mistaking it for the more common red root pigweeds. But in year three, farmers become alarmed.

Palmer and waterhemp don’t have hairs on the weed stem. At the three-leaf stage, the farmer can hold the weed stem up to the light and look for “rough hairs on the stem near the growing point,” normally associated with normal pigweed species.

If there are no hairs, the next step is distinguishing between Palmer amaranth, which has a petiole as long or longer than the leaf blades, while waterhemp petioles are shorter than the leaf blade.

Go to NDSU’s Palmer amaranth web page to find aids for identifying the weed. NDSU links to Purdue sites but is also working on generating more of its own materials on the weed.

The North Dakota soybean organizations are organizing a second tour to visit infested areas in areas of western Nebraska.

Indiana researchers have come to the conclusion that “waterhemp loves wet years; Palmer amaranth loves dry years,” Ikley said. He said concentrating on hand-picking can be effective and the workload declines with vigilance.

Ground game

Chandra Langseth, the North Dakota State University Extension ag and natural resources agent for Richland County, said the weed was found in her county in late September.

Officials believe the seed came in with some livestock feed that was sourced in a state to the south, but declined to say even what part of the county was effected, not wanting to label a producer as a pariah for unwittingly bringing it in.

“Unfortunately, in Richland County, they were pretty large plants, so we do think they went to seed,” she said. On the positive side, they did discover them before the end of the season so are in a better position to address the problem in 2019.

Langseth said there have been lots of warnings and awareness of Palmer amaranth compared to the closely related waterhemp, but they are hard to distinguish. The strategy for controlling it — hand-weeding, tillage and “some pretty serious herbicide” in years to come.

Ikley says Purdue University scientists calculate it will cost at least $50 an acre in herbicides to conquer them, not counting the materials (adjuvants) to spray the chemical with, or the application costs. “You do need a pre-emergence herbicide down — two modes of action, and three if we can get it. We do have to have follow-up control when waterhemp is 2 inches tall,” he said.

Tiling takeoff

Kale Van Bruggen, an attorney with Rinke Noonan law firm in St. Cloud, Minn., talked about water management and wetlands regulations. He said that despite a poorer farm economy, many are still working to improve drainage of soils through subsurface drainage (tiling) and surface draining.

Van Bruggen talked about neighbor-to-neighbor issues, and upstream and downstream issues, but most of the questions related to wetland determinations and federal regulations related to the so-called Swampbuster provisions that are designed to prevent farmers from draining wetlands and then farming them.

He said the Trump administration has had a perceived positive effect on regulatory conflicts with farmers, in part because it has “codified” some farmer-friendly policies, including making more clear what it means to have “certified wetland determinations.” “That is what gives them the certainty when planning their drainage projects,” he said.

For example, he said, the Natural Resources Conservation Service in December revealed a new interim rule that codifies what is certified, identified by when in history they were “determined” under earlier farm bills.

All this is adding confidence to farmers. In North Dakota, tile drainage has taken off in the past five years as farmers have seen yield benefits and reduced impact from weather. “That (enthusiasm) is going to be countered by markets and how strong the farm economy is and whether the financing is really there to put these systems in place,” he said.

Joe Ikley, North Dakota State University Extension Service’s new weed specialist, urges farmers to get on top of Palmer amaranth weeds to avoid bigger expenses later on. He spoke Feb. 12 at the Northern Corn and Soy Expo at the Fargodome.
Kale Van Bruggen is a lawyer with the Rinke Noon law firm in St. Cloud, Minn. He says farmers in northern North Dakota and Minnesota are gaining confidence in the value of field drainage and that the Trump administration’s agencies have improved certainties in regulations they need to know to plan projects.