May 1, 2003

 

Dry Seedbeds Require Special Tactics or Rain

This year many North Dakota farmers face dry surface conditions as they seed their crops. Dealing with such conditions isn't easy, according to Duane Berglund, agronomist for the North Dakota State University Extension Service.

He suggests that, whether fields are dry or not, farmers stick as closely as possible to the recommended planting schedule for each crop. Late planting can sharply reduce small grain yields in flax, corn, canola and mustard, especially in a year when temperatures are above normal and spring planting operations are ahead of normal.

"Under dry seedbed conditions planting on schedule may result in uneven stands," Berglund says. "But that’s preferable to planting too late. If rains do come later, most seeds will still germinate if adequately protected with a seed treatment. Some soil crusting could present a problem if seeds are slow to germinate, so farmers should be aware of this possibility."

To minimize problems from lack of moisture, Berglund suggests tilling at a shallow depth and cutting down on seedbed operations before planting. Direct seeding or no-till may be the best option this year in many extremely dry regions of North Dakota. He also suggests using postemergence herbicides rather than preplant soil-incorporated herbicides that require tillage and can cause additional soil drying. Soil applied herbicides require soil moisture to activate them against most germinating weed seeds.

"Plow pony press drill planting should be at a shallow depth," Berglund says. "Roots will not grow through dry soil even if seeds germinate. Use deep furrow hoe drills, when available, to reach soil moisture. Small grains and flax can be drilled directly into standing sunflower or soybean stubble with disc opener drills."

A double disc drill, he says, is not as effective as a no-till drill, a hoe drill or a narrow tine equipped airseeder in seeding to moisture in standing stubble. He suggests harrowing first and scattering the straw or previous crop residue prior to seeding.

"If newly emerged weeds are present, use a nonselective, burn-down herbicide before seeding," Berglund says. "Some residual weed control may be present from dinitroaniline herbicides (Treflan, Prowl or Sonalan) used in 2002, but be ready to control volunteer sunflowers or other crop volunteers as they emerge with the newly seeded crop."

Berglund offers 10 suggestions to minimize the effects of planting into dry soils:

• Avoid excess tillage prior to planting. Each tillage operation causes soil moisture losses (1/3 to 1/2 inch).
• Use shallow tillage (3 inches or less) to destroy weeds and firm the seedbed.
• Avoid use of premerge soil-incorporated herbicides on crops where post emergence herbicides are available and economical to use.
• Plant small grains directly into standing sunflower stalks, soybean, canola and dry edible bean stubble.
• Crops like corn, sunflower and dry edible beans can be planted deeper (2 to 3 inches maximum). Flax, mustard, canola, proso millet, or buckwheat should be 1 inch or less in planting depth. Intermediate planting depths of 1 to 2 inches are best for wheat, durum, barley, oats, peas, lentils and soybeans.
• In general, large-seed-sized varieties of wheat, durum, oats and barley can be seeded slightly deeper than small-seed-sized varieties.
• Seed treatments on small grains should be uniformly applied at labeled rates to maximize seedling emergence. Uneven seed treatments can cause erratic stands.
• If rains come after planting, watch for soil crusting. Break soil crusts by light harrowing or using a rotary hoe.
• Consider post-plant applications of nitrogen in the form of urea if good moisture conditions develop later. Rain is usually required in 48 hours after application to reduce nitrogen losses due to volatilization.
• If fairly good stands are established, but dry soil conditions continue, plan a good weed control program to help conserve soil moisture for crop growth and development.

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Source: Duane Berglund, (701) 231_8135, duane.berglund@ndsu.nodak.edu
Editor: Rich Mattern, (701) 231-6136, richard.mattern@ndsu.nodak.edu