|
|
AgAlerts 2008 From Griggs County
|
Issue # 2, May 7, 2008
Corn germination begins when soil
temperatures approach 50 degrees F. Soil temperatures at the Dazey NDAWN
station on 5-5-08 were 51 degrees on bare soil and 43 degrees in turf.
Corn requires between 120-125 growing degree days (GGDs) to emerge. If
corn was planted on May 1st, 34 GGDs have been accumulated at the Dazey
station. The average GGDs per day have been 7. At this rate,
emergence should occur on 5-17-08, assuming current temperatures. The corn
seed would have been in the soil for 17 days. What is needed at this time
is a warm rain and warmer temperatures.
If you would like to see what GGDs have accumulated for your
corn acres, go to the NDWAN
site. At this site you can click on any of the stations listed on the map
of ND. This will give you the date from the previous day. If you
click on applications from the left side menu, you can select a crop and select
GGDs. At this point you can enter your planting dates and the GGDs will be
determined from the NDAWN site you selected. Click on the following link
to go directly to corn
GGDs.
The way the weather has been this spring, it
is hard not to rule out the possibility of frost. Historical last spring
frost dates for Cooperstown have been May 11 for a 28 degree F frost and May 21
for a 32 degree F frost.
Small Grains: Are fairly tolerant to frost
injury until the tillering stage. Up to tillering, the growing point is
still below the soil surface. Small grains are tolerant to temperatures at
about 20 degrees F.
Winter Wheat: Since spike development begins
around the 5 1/2 leaf stage, frost at this time could cause damage to the
developing spikelets which may result in loss of kernels. Damage will be
noticed upon head emergence. The head and awns on the top of the plant may
appear white.
Corn: The growing point is protected under the
soil until the plant reaches the V5 growth stage (five true leaves). Leaf
loss above the growing point will have a small effect on corn growth and yield
when injured in the early growth stages. The check to see if there has
been frost damage, pull a plant and cut the stem and check the growing
point. The growing point should be white to a yellowish in color. If
it is discolored, damage might have occurred. Uninjured growing points
should recover in 2-3 days.
Soybean: Have an "active hypocotyl"
type of emergence, thus the growing point will be above ground upon
emergence. Soybeans are quite sensitive to frost and are easily damaged at
the 28-32 degree F range. If seedlings have been hardened off by prolonged
cool temperatures, a 28 degree F temperatures can be tolerated. Soybeans
in the unifoliolate leaf stage are slightly more frost tolerant than soybeans in
the first or second trifoliolate stages.
Each year we see some problems caused by
cutworms or wireworms. The first thing growers notice is irregular spots
in the field where the crop has been damaged or poor emergence. Each
insect will feed in a different way.
Cutworms: Cutworms are the larval form of moths. The larvae
are greenish-brown to greenish-gray. The head is pale brown with darker
brown freckles. Mature worms are 1 1/2 inches long. The eggs were
laid last summer or fall in the soil where corn, soybeans or sunflower are now
being planted. The eggs have hatched and the growing larvae are hungry!
When suspected cutworm damage is found, check for live cutworms around the
damaged plants by digging in the soil at the base of damaged plants. Count
and record the number of damaged plants. Note the size of the cutworms
being found. The treatment threshold has been reached if 3 to 6% of the
plants are cut and small larvae (<3/4 inch) are present. For corn, consult
the 2008
North Dakota Field Insect Management Guide for products registered for
treatment.
Wireworms: Wireworms are one of the most difficult insects to
detect and one of the hardest to control. They will completely consume the
inside of a germinating seed. It will also consume any fresh tissue of
seedlings and can significantly reduce plant stands. If you have seedling
emergence that is somewhat irregular, start digging for wireworms in the soil
around the seed or seedling. Wireworms are elongate, heavily segmented,
pale yellow to brown wire-like worms that vary in length for 1/2 to 1 1/2
inches. They tend to prefer lighter textured soils. In the spring,
after overwintering in the soil, wireworms migrate closer to the soil surface
and seek germinating seeds as a food source. For wheat consult the 2008
North Dakota Field Insect Management Guide for products registered for
treatment.
Each spring several question arise concerning
lawns damaged by dog urine. Myths are abundant over what causes the
damage. Does female dog urine is more damaging than male dog urine do to
higher acidity? By adding tomato juice to the dogs diet or baking soda to
its water help this problem?
Let's look at the cause that produces these spots. Dog
urine and feces, in small amounts can have a fertilizer effect but in larger
amounts can cause lawn burn or dead patches. Most spots will recover but
sometimes reseeding or sodding will be required.
The way in which a female or male dog urinate can have an
effect on lawn damage. Both females and male dogs will generally squat to
urinate while in the puppy stage. Males will begin to lift their leg
around a year old. A dog that squats to urinate will have more effect on
lawn damage than will a male that lifts their leg. Hence females have a
greater chance of lawn damage than males. But males can have a greater
effect on small shrubs and plants. The amount of lawn burn is related to
the nitrogen concentration of the urine. the pH of urine has little
effect. So adding pH altering materials in to food or water should have
little effect on lawn burn. Increasing water intake is one way in which to
reduce the nitrogen concentration and decrease the possibility of lawn burn.
Lawns can recover on their own, but it takes time.
Heavy watering in area of lawn burn can help reduce the recovery time.
Other preventive measures are to have a place where dogs can go and not hurt
turf. Such as a graveled area, kennels, or walks in areas where turf
quality is not a problem. The amount of protein that is fed in the diet
can help reduce nitrogen concentrations. When dogs are not active, feed
lower protein diets. Canned dog food normally has lower protein than dry
rations.
The following link, "Dog-On-It
Lawn Problems", by Dr. Steve Thompson, DVM, Director Purdue University
Veterinary Teaching Hospital Wellness Clinic, West Lafayette, Indiana, is an
excellent article on dog damaged lawns.
The following pictures are of lawn damage the spring of
2008.
Picture #1, Notice the lush growth surrounding the burned areas.
Picture #2, Female urine areas.
Picture #3, Female urine areas.
Picture #4, Male urine areas.
Picture #5, Female urine areas.
Picture
#1
Picture #2
Picture
#3
Picture
#4
Picture #5
Please Contact Our Office For Additional Information
E-mail: john.swenson@ndsu.edu
Go to the 2008 AgAlert Index Page