Traill County Ag Alert Newsletter
June 27, 2008
RAINFALL & GROWING DEGREE DAYS (GDD)
Location
Mayville Hillsboro
Galesburg
Corn GDD 577
589 573
Compared to 2007 -209 -206
-195
Wheat GDD 1360 1366
1370
Compared to 2007 -319 -325
-289
Rainfall since June 1 2.61 inches 3.81 inches 3.79 inches
NDSU ANNUAL FIELD DAYS THIS
SUMMER
July 14 -Agronomy Seed Farm, Casselton
July 15 - Carrington Research Extension Center, Carrington
July 17 - Langdon Research Extension Center, Langdon
July 23 - Turf Field Day, NDSU Campus, Fargo
July 29 - Oaks Irrigation Research Site, Oaks
August 2 - Horticulture Research Field Day, Absaraka
For these and other events this summer (including Pulse Crop Tours, Canola Days, etc…), visit http://www.ag.ndsu.edu/research/fielddaydates2008.htm or contact a Research Extension Center.
REPORT OF LOSS IS GONE
North Dakota Report of Loss has been changed as of April 3, 2007. The North
Dakota Pesticide Act (4-35-21-21.3) states that before civil action is taken to
seek reimbursement for damage, a person must notify by certified mail the
pesticide applicator of alleged damage within the earlier of:
Upon notifying the applicator as required, the person seeking reimbursement for the alleged property damage shall permit the applicator and up to four (4) representatives of the applicator to enter the person’s property for the purpose of observing and examining the alleged damage. If the person fails to allow entry, the person is barred from asserting a claim against the applicator.
RECENT FIELD OBSERVATIONS
OF COLORADO POTATO BEETLE
Adult Colorado potato beetles are emerging now from overwintering sites. The
adult is 3/8 inch long, with oval body and a yellow-brown color with five black
stripes on each wing cover. Eggs are laid on the underside of leaves in clusters
of 10 to 30 and are orange colored when ready to hatch. The larvae are 1/8 to
3/8 inch long, brick red to light orange in color. Both adults and larvae feed
on potato foliage.
The treatment recommendation is that spraying be initiated at first egg hatch. Best results have been achieved by flagging the first egg masses that can be located, monitoring these daily, and spraying at 15 to 30% hatch.
SOYBEAN APHID
Very low numbers of soybean aphids have been found in soybeans growing in
the Red River Valley region of North Dakota and Minnesota (Crookston). The
current temperatures between 77 and 86 F are optimal for soybean aphid
development. The pre-reproduction period takes about 5 to7 days before aphids
begin birthing little nymphs. When scouting soybean field, remember the many
different insects inhabit soybean fields throughout the season. Be sure to
properly identify aphids and any look-alike insects - thrips, insidious flower
bugs, spider mites, leafhoppers, and so on. A good reference is the
Identification of Soybean Aphid and Look-alike Species, published by the
North Central IPM Center.
http://www.ncipmc.org/alerts/soybeanaphid_id.pdf
It’s important to be aware of aphid predators, because they play a major role in reducing early population of soybean aphids. Research results have indicated that early-season application of insecticides for control of low populations of soybean aphids has caused more harm than good.
SOYBEAN/DRY BEAN - BEAN
LEAF BEETLE
Bean leaf beetles have been increasing in North Dakota over the past years
Adult bean leaf beetles are emerging from overwintering sites and moving into
soybean or dry bean fields. The adults are yellow to reddish-brown and three to
four black spots with a black border on wing covers. Early feeding injury to
leaves appears as small round holes between the leaf veins. Treatment thresholds
based on defoliation - 50% defoliation during early vegetative, 40% defoliation
during pre-bloom, 35% defoliation during bloom and 20- 25% defoliation during
pod set to fill. Late season feeding on the foliage and pods by the new adults
that emerge in August appears to be more important than early season feeding.
This may increase the risk of virus transmission and cause secondary infections
(rotting and discoloration) from fungi and bacteria.
GROWTH STAGING CORN
Being able to properly identify the growth stage of your corn crop is
important to ensuring that management practices are applied at the appropriate
time. The leaf collar method of growth staging corn is the method most often
used in recommendations related to the timing of herbicides. When growth staging
your crop you should begin by obtaining a representative sample of plants from
the field or part of the field of interest. Ten plants should be selected at
random. If emergence has been uniform, you can probably get by with fewer
plants.
Remove any soil attached to the plants so that you are able to observe the roots and crown. The number of leaves defines the vegetative stages of corn (i.e. V1 equals the 1st leaf stage). Care must be taken to ensure that the earliest leaves are included when counting leaf numbers. The first leaf is small and often dies and is torn from the plant during early plant development. The first leaf has a blunt tip. Look for sheath remnants at the crown of the plant if you suspect that the first leaf (or second for that matter) is missing. Count only those leaves that have a collar. Do not exclude leaves that have been damaged by hail or frost. The total number of leaves that a plant will developed is more or less fixed for a given hybrid; additional new leaves will not replace leaves that are stripped from the plant. In order to determine the growth stage of older plants that have lost their lower leaves, uproot the plant and split the stem with a knife through the root ball. At the very base of the stem, identify the first visible internode. Internodes are the white area between the more yellow bands of the nodes. The first obviously visible internode should about 2 to 3/4 inch in length. The node directly above this internode will be the fifth node, and the leaf arising from this node will be the 5th leaf. Find that leaf and continuing counting leaves from that point.
OPTIMAL GROWTH STAGE TIMING
FOR FUNGICIDE APPLICATION TO SMALL GRAINS FOR SCAB MANAGEMENT
The optimum growth stage for applying fungicide for scab control in wheat,
the Feekes 10.51 stage, is the same for all classes of wheat (winter, spring and
durum). Applying fungicide during early flowering helps protect against the
fungus infection when it can do the greatest damage. The length of time from
head emergence to the beginning of flowering is temperature dependent, but
usually takes about three days. Experience has shown that it is better to apply
fungicide too early rather than too late, so the beginning of heading is a good
indication of when to get serious about spraying for scab in wheat.
TIMING IN BARLEY
Flowering in barley begins just before head emergence, so barley florets are
not overly susceptible to scab infection. Although scab infections do not
generally impact yield greatly, the fungus is able to infect the glumes and
produce DON (vomitoxin), which impacts the value of the grain in the market. The
optimum stage for applying fungicides to protect the glumes of barley from
infection is when the spike is fully emerged from the boot (Feekes 10.5). With
barley, the appearance of the first spikelet from the boot, like the first plant
on the left in the photo above, is a good indication that the best stage for
spraying is only a few days away.
CROP YELLOWING
Following the last couple weeks of rainy weather, a number of wheat fields
are showing yellow patterns. The time of wheat head emergence is a time of heavy
requirement for nitrogen, and some fields are a little short in areas. Look for
yellowing on lower leaves, with newer leaves emerging greener. For most fields,
yellowing is either seen in depressions where water may have sat for many days,
or in the coarser-textured hilltops/slopes where leaching occurred. If the
percentage of acres showing these symptoms is large, a post-anthesis application
of 30 lb N/a as 28% might increase protein content about 1/2%. 30 lb N as 28%
will cost about $21/a plus application, so check to see if this might be
profitable.
Franzen has seen problems with nitrogen availability, sulfur deficiency and zinc deficiency. Nitrogen would be the result of leaching in sandy soils, or denitrification in eastern counties due to waterlogged/ poorly drained soils. Look for yellowing on lower leaves, with the new leaves emerging greener. There is still plenty of time to side-dress traditionally, or dribble 28% between the rows (not over the whorl!!!) using a long hose or drop-nozzle. Look for sulfur deficiency on coarse-textured hilltops and slopes with lower organic matter. Many areas have received large rains during a day or two, and any residual sulfate may be gone. Look for yellow upper leaves, with lower leaves remaining greener. If there is a zinc problem there will be stunted plants with yellow-striped upper leaves, usually on low organic matter hilltops and slopes. Foliar application of one quart/acre of zinc chelate will help to snap the corn out of its deficiency. DO NOT APPLY WITH HERBICIDE. Apply in a separate application.
There have been reports of failures to nodulate with granular inoculants this spring. Check soybeans when the plants have about 3 trifoliates. If there is no nodulation, application of supplemental N will be needed to carry the crop.
NDSU Extension Service, North Dakota State University of Agriculture and Applied Science, and U.S. Department of Agriculture cooperating, Duane Hauck, Director, Fargo, North Dakota. Distributed in furtherance of Acts of Congress of May 8 and June 30, 1914. We offer our programs and facilities to all persons regardless of race, color, national origin, religion, sex, handicap, age, Vietnam era veteran status, or sexual orientation; and are an equal opportunity employer.
Go to Traill County Agriculture Program Page
Traill County Extension Office
P.O. Box 730
Hillsboro, ND 58045
701-636-5665 or toll-free1-877-843-6383
Contact us at: NDSU.Traill.Extension@ndsu.edu