ISSUE 1 May 6, 1999
MANAGE YOUR RISK FOR CORN AND SOYBEAN WEED CONTROL
The pluses of early control of weeds and application flexibility
around later weather
conditions make preemergence herbicide application planning a good risk management tool.
Low crop prices have had many farmers cutting corners and
considering a total_post
approaches to weed control. It is not surprising as surveys have shown that 80% of soybean
growers and nearly 70% of corn producers are only applying post products. Postemergence
weed control does allow you to visually match the herbicides to the weeds. And, there are
several excellent post programs.
However, applying only post products during the narrow application
windows allowed in
North Dakota and Minnesota can prove that only post weed control is more difficult, more
risky and can be more costly. Only a few days of windy or rainy weather, an equipment
breakdown or even being later on the local, commercial applicator's list of fields to be
sprayed can cause problems. If the growing conditions are excellent, you can bet the weeds
are growing rapidly. Less than ideally timed applications cause weed escapes that may cost
you more in the long run.
Consider the preplant incorporated, preplant and preemergence corn
and soybean options
as well as burndown programs that will gain early weed control and in the case of the residual
chemicals, an even wider window before post applications.
NDSU FIELD DAYS SCHEDULE
Below is a listing of NDSU field day tours and other special events.
Exact starting times will
be given at a later date via this newsletter or other media channels.
ALTERNATIVE CROP CIRCULARS AVAILABLE
To those interested: the NDSU Extension Distribution Center now has
a supply of newly
revised and developed circulars on Field Peas, Flax, and Alternative Crops Performance. Refer
to the following when ordering:
Flax Production in North Dakota A-1038
Field Pea Production A-1166
1998 North Dakota Alternative Crop Variety
Phone your order in or write to:
NDSU Extension Distribution Center, Morrill Hall 10
Box 5655, Fargo, ND 58105
Phone: (701) 231-7883
Fax: (701) 231-7044 or email email@example.com
These publications are also available from your local NDSU Extension Service County offices.
CORN EMERGENCE PROBLEMS
Corn should begin emerging after about 100 to 125 GDDs have
planting. This can be anywhere from one to three weeks after planting depending on the
temperature. Heres a list of a few common things to look for if you encounter an emergence
problem in corn this spring.
Duane R. Berglund
USING BIN RUN SEED
Recent phone calls indicate many producers are still struggling with
planting decisions including the use
of bin run seed. Percent germination, diseased kernels, presence of weed seed, purity, and inert material
are factors that impact crop stand and ultimately production and should be evaluated before using bin run seed.
Germination of seed used for planting should be high. Acceptable germination is:
To determine germination simply lay 200, or more if inclined,
randomly selected seeds from
your sample on heavy duty paper towels, role the towels up and secure the role with paper clips,
wet the towel and place it in a bread bag. Then place it in a location that remains about 50 to 60o F.
After two days count the germinated seed and divide by the total tested, and you have percent
Discolored black, pink, grayish and shriveled seeds are general
indications of disease. A diseased
kernel is less likely to germinate properly and when it does seedling disease may occur. Seed from
a field infected with Fusarium head blight when replanted is likely to develop seedling blight
resulting in seedling mortality and stand loss.
Shriveled and low test weight seed may germinate well but the vigor
of the young seedling is often
considerably less than from plump seed. These weak seedlings are less competitive with weeds and
less likely to recover from early season moisture or temperature stress.
Grain mechanically dried at temperatures over 110o F is
probably not suitable for seed. Drying
at high temperatures injures the germ.
Whenever bin run seed is used having it conditioned will eliminate
many of the potential
problems previously described and will pay dividends. Conditioning eliminates light kernels
which includes most diseased kernels, weed seed and inert material.
Research indicates that high plant stands are critical for optimum
yield of small grains. In
wheat and barley optimum plant populations are about 1.25 million plants per acre, or 30 plants
per square foot.
If using certified seed, seed weight and percent germination are
percent germination has already been described, determining seed weight is even simpler.
Count out 1,000 kernels and weigh them using a scale that's accurate to a tenth of a gram or
a hundredth of an ounce; bathroom scales won't cut it here.
Most sensitive scales weigh in grams. This is easily converted to
pounds by dividing into 453.6
(there are 453.6 grams per pound). If your 1,000 kernels weigh 32.4 grams then (453.6 ÷ 32.4)
x 1000 = 14,000 kernels per pound. Or if your 1,000 kernels weighed 1.14 oz, then (16 ÷ 1.14)
x 1000 = 14,035 kernels per pound. If the germination is 90% and you want to plant 1.25 million
live seeds per acre, calibrate your drill for 1,250,000 ÷ 14,000 ÷ 0.90(percent germination) =
99 lbs/A, or 1.65 bu/A if the seed weights 60 lbs/bu.
Michael D. Peel
Small Grains Extension Agronomist