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ISSUE 6  June 7, 2001



Fields are scattered in condition and planting progress, depending on where the rains fell and soil type. We are seeing not only crusting on some of the fields but also simply slow emergence. Some beans I planted three weekends ago in Fargo clay are just now emerging while some planted in a sandy clay soil emerged about mid-week last week. Most soybean seed that were planted within the last week should be emerged by week's end. Although alternative "cover" crops are limited if planting extends past the second week of June, depending on crop insurance alternatives, some forage (perhaps annuals such as millets in the southern Red River Valley or sorghum-sudan rather than perennials will act as cover crops); sunflower, dry beans (if you have a market and crop insurance coverage); soybeans (if you can find any seed as commercial companies will be closing their doors as will crop insurance companies shortly, so they won't have to fend off late-planting product inquiries, even if seed is available at a germ above 70%); buckwheat, or sorghum as either forage or seed (seed for either needs a consistent 60F or above soil temperature and a maturity that can be harvested before frost) may be alternative late crops for the region.

Here are some suggested alternative crop to review:

More information and possibly some suggestions can be obtained at the USDA niche crop site, too, at:


Remember these considerations when reviewing alternative crops with very late planting: any rotation restriction/problems for next year that the alternative crop may present; weed problems in this new crop and the seed banks within each field (some of these alternatives have very few herbicides); crop uses and markets and maturities available as well as diseases and pests; seed availability and cost for planting rate needs.



Soybean seed can begin germinating when the seed has absorbed enough water to equate to about 50% of the dry seed weight. So under adequate soil and air temperatures and moisture regimes, soybean can germinate in less than half a day. Emergence from soil depths may take an additional two to three days, depending on adequate growth conditions. The optimum temperature for soybean germination is 86F, thus seed planted into soil at 50F germinates slowly, often with reduced emergence. Like corn, soybean yield is affected by temperature or moisture stress, especially if it occurs during flowering and pod fill. However, unlike corn, soybeans produce excess flowers on the plants. Usually only 25-40% of a plant's flowers develop into mature pods with the remaining 60 to 75% of the flowers or pods aborting and never contributing to yield. Day length also affects most soybean varieties grown in North Dakota and Minnesota so that late-planted soybeans may hasten their development toward maturity with less yield loss than other late-planted crops. Soybeans respond differently than corn to delayed planting. Soybean flowering is closely related to photoperiod (the length of night versus day periods) and the shift in soybeans from the vegetative stage to the flowering stage is due mostly to changes in the length of darkness and to some extent by temperature. Once the dark period begins to lengthen in late June, varieties are influenced to flower with high temperatures hastening this process. Flowering is very closely triggered at about the same time, even with soybeans of different maturities that are planted late. Yield is generally reduced with delayed plantings, due to a decrease in days to generate growth before flowering and a decrease in days to fill seed as soybean maturity is pushed to finish by photoperiod effects. Remember to consider late planting effects on soybean yields when evaluating alternative crops.



Soybean growers who are thinking about saving a few dollars this spring by planting bin-run soybeans need to evaluate the seed carefully. Severe quality problems triggered by variable conditions last fall could make planting bin-run soybeans risky and costly. Reports of some low germination ratings on seed as well as poor condition seed such as splits, chips, and cracks can limit potential yields. Look out for mechanically damaged seed, even from seed lots with normal handling. Also, don't plant seed that shows any storage mold, that is, beans that have been harvested at an ideal moisture (14%) but stayed at that moisture or gained moisture leading to molding problems. Sclerotinia white mold can also be transferred with the crop if seed was harvested from infected fields. White mold can remain in soil for several years, through several rotations, and show up in years under cool soil temperatures and high soil moisture. It can also be transferred to the soil from host plants such as broadleaf weeds including: lambsquarters, velvetleaf, red_rooted pigweed, common ragweed and wild sunflower. Years of trials by the Illinois Crop Improvement Association, Ohio Seed Improvement Association and North Carolina State University have shown that professionally grown seed can out-yield bin-run by 1.9 to 2.7 bushels per acre. The perceived cost of bin-run is the primary reason many farmers go to the bin; however, the real costs go far beyond the market price of soybean seed. The hidden costs of cleaning, transportation, storage, interest, time and labor easily add dollars to the bin-run price tag. Farmers that bin-run seed year after year also lose out on the latest genetic yield improvements, such as developments in Phytophthora root rot resistance. Only soybean seed with good accelerated aging germination that is clean should be used for planting, especially on late-planted fields.

Denise McWilliams
Crop Production Specialist




Flax is an alternative oilseed crop that can be late planted with reduced yield potential. How late is the question many ask in North Dakota this year. Below are data from studies at the NDSU North Central Research and Extension Center at Minot, ND.

Flax seeded in the middle of June, late June and early July, periods 4, 5, and 6 yielded 32, 52 and 84 percent less than flax seeded in early May, period 1, see following table. This would indicate that seeding flax in early or mid-June usually results in significant yield reduction.

Flax seeding date studies, Minot

Seeding periods

Yields* (bu/A)

1st (Early May)


2nd (Mid-May)


3rd (Late May)


4th (Early June)


5th (Mid-June)


6th (Early July)


Nine years (1977-1985)
* Yields averaged over 10 varieties.

Mid June planting of "early" varieties yielded 79 percent of their early May planting while late maturing varieties planted in mid June yielded 42 percent of their early May planting. Please note: NorLin was the highest yielding early variety when seeded the middle of June - period 4. These data support the recommendation to plant early maturing varieties when seeding in June.

In summary this nine-year study of planting date of flax indicates that delayed flax planting will reduce yield potential. Flax planted in periods 2 through 6 yielded 93, 79, 68, 48 and 16 percent, respectively, of flax planted in period 1 when averaged over all varieties.



Most years in North Dakota, a number of sunflower fields are planted late or replanted. The many reasons for this include: extremely cold or wet conditions, wind erosion, insects (cutworm or wireworm), diseases, hail and frost. This wet year, 2001 will go down as one of the later planting of sunflower and many other crops in some areas of the state.

Research on late planted sunflower has been conducted at various North Dakota NDSU Research Center sites. Results of these studies are shown below:

Table 1. Sunflower yields* (lb/A) as influenced by planting dates at Prosper and Carrington, ND

Approximate planting date


% oil



June 1




June 15




June 30




July 15




*Average 3 years, 2 locations
** Sunwheat 101 - early semi-dwarf sunflower

Table 2. Sunflower oilseed yields*
Early vs. late planting

Planting time





Mid May





Early June










*5 year ave. Yields - lbs/A

When planting sunflower late (after June 5) itís suggested to plant early maturing hybrids. Selection of short season sunflowers will increase the chance of reaching maturity in the northern areas of North Dakota and Minnesota. Planting of non-oilseed or confectionary sunflowers is discouraged in June.



Late planting in some eastern and northern regions of the state due to extremely wet field conditions has created questions on the management of abandoned fields. What can and should be planted to control erosion, help in control of weeds and aid in reducing excessive soil moisture? Acceptable cover crops are usually listed or are available from crop insurance agents. In most cases some type of annual crops should be considered for cover.

Acceptable cover crops:

1) Acceptable cover crops include the following, provided they are not prior established crops (e.g., alfalfa) and are planted for erosion control, green manure, etc., and are generally left in place for only one growing season:

a) Annual, biennial, or perennial grasses and legumes (legumes such as prior established alfalfa, soybeans, or peanuts are not considered a cover crop) including sorghum-sudangrass crosses, sudans, millets, and volunteer stands other than weeds.

b) Barley, oats, wheat, and other small grains qualify, provided they are not harvested for grain or seed.

2) The approved cover crops may be hayed (chopped for silage) or grazed after the final planting date for the insured crop only if allowed by prevented planting policy provisions, but may not be harvested for grain or seed.

3) The above cover crops are commonly recognized in the farming community as cover crops and are consistent with those previously approved by the USDA for FSA administered programs.

4) Corn or milo planted for any use is not considered to be a cover crop.

Note that no cover crops can be harvested for seed or grain from prevented planted land. Haying (chopping) or grazing is allowable if only the producer uses for his own livestock. Hay cannot be harvested and sold nor can cover crops be leased out to others for grazing. Producers should check their own crop insurance policies closely or consult with their respective crop insurance agents on the various options. Also producers should check with both The Farm Service Agency and the NRCS local office to insure that the cover crop sown will be in compliance for adequate crop residue cover.

Duane R. Berglund
Extension Agronomist

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