ISSUE 15 AUGUST 12, 1999
CRISIS EXEMPTION ISSUED FOR WARRIOR TO
CONTROL GRASSHOPPERS IN FLAX
The North Dakota Department of Agriculture issued a Section 18
Crisis Exemption for the use
of Warrior (lambda-cyhalothrin) to control grasshoppers in flax fields. It may be applied by ground
or air in a minimum of two gallons of water by air and ten gallons by ground. Warrior is a restricted
The rate is 3.84 fl. oz. (0.03 lbs of A.I.) per acre.
The maximum number of applications is two.
The post harvest interval is 14 day; therfore, do not apply within 14 days of harvest.
Applications may be made from August 6, 1999 and continue through August 20, 1999.
The user must have a copy of the crisis label in their possession. A
copy is available through the North
Dakota Pesticide Training and Certification Program at:
If you have any questions or concerns regarding this declaration
please contact David Nelson, ND
Department of Agriculture (701- 328-4765).
EPA DECISION ON PESTICIDE SALES TO HAVE
LITTLE EFFECT ON N.D. PRODUCERS
In early August the Environmental Protection Agency announced that
it had reached agreements
with pesticide manufacturers to stop the sale of methyl parathion for most uses and to significantly
limit sales of azinphos methyl. Both of these products are classified as organophosphate pesticides.
In North Dakota, methyl parathion is also marketed under the trade
name Penncap-M, and azinphos
methyl as Guthion. Due to the types of food crops involved in this EPA action, the decision will have
a limited effect on the states producers.
"Primarily, fruits and vegetables are being affected. The
emphasis has been put on food items
represented in childrens diets," says Phil Glogoza, extension entomologist at NDSU.
This initial EPA focus on organophosphate pesticides stems from the
Food Quality Protection Act,
passed by Congress in 1996. This legislation set tougher standards to protect infants and children
from pesticide risks and charged the EPA with enforcing those standards.
Under the agreement EPA reached with manufacturers, methyl parathion
can no longer be used
on any fruit, nor on carrots, succulent peas, succulent beans and tomatoes--all of which are being
defined by the EPA as "childrens food." Other canceled food uses include artichokes, broccoli,
brussels sprouts, cauliflower, celery, collard, kale, kohlrabi, lettuce, mustard greens, rutabagas,
spinach and turnips.
The crops that can still receive methyl parathion applications
include alfalfa, barley, cabbage,
corn, dried beans, dried peas, lentils, oats, onions, rape seed (canola), rye, soybeans, sugarbeets,
sunflower, wheat and white potatoes.
North Dakota small grain producers have used methyl parathion to
control aphids and grasshoppers
in wheat, but there are several other products available for this purpose. And while methyl parathion
remains labeled for dry beans in North Dakota, few producers have used it in recent years.
But methyl parathion has been one of the few insecticides registered
for canola, so producers have
been relying on it to control flea beetles, grasshoppers and caterpillar pests such as the diamond-backed
moth and the Bertha army worm, Glogoza says. However, within the last month, the EPA registered
another insecticide for canola, Capture (bifenthrin), which promises better control of the same insects
than does methyl parathion.
"At one time, methyl parathion was probably one of the most
common products used in sunflower,"
Glogoza says. "Other products now have taken on a more common usage than methyl parathion, although
there are still cases, such as for the control of seed weevils and banded sunflower moths, where it is the
preferred product under certain circumstances."
When it comes to azinphos methyl, even fewer North Dakota producers
are affected by the EPA action,
which establishes a maximum seasonal use rate and increases the pre-harvest interval for this pesticide.
The EPA has lowered the tolerances of azinphos methyl, or Guthion, for pome fruit (apples, pears, quinces
and crabapples) from 2.0 parts per million (ppm) to 1.5 ppm. Beginning in the year 2001, that tolerance
drops to 1.0 ppm.
"Guthion is not that widely relied upon in North Dakota. The
only crop where its used is potatoes, and
its used on a limited number of acres," Glogoza concludes. "Potato producers will alternate Guthion with
other pesticides so that Colorado potato beetles are exposed to products with different modes of action.
The use of different chemistry can help limit the potential for insecticide resistance."
In addition to methyl parathion and azinphos methyl, EPA
Administrator Carol Browner says the agency
will review the 37 other major organophosphate pesticides currently registered. She expects actions based
on that review to come by the end of next year. Meanwhile, during the past three years the EPA has
registered 48 new, safer products that it says constitute lower-risk alternatives to the organophosphate pesticides.
RED SEED WEEVIL UPDATE
Numerous reports continue to come in that indicate the general
nature of seed weevil infestations
across the region. Though weevil populations infesting fields are not large, they are hovering around oilseed
threshold numbers of 8 to 10 weevils per head. Continue to scout and treat when warranted.
CORN BORER UPDATE
Moth captures at the trap at the Oakes Research Station have
increased quickly over the past five days.
This would indicate the beginning of the second generation flight. Corn growers in these south central
counties may want to monitor for late developing larval infestations. Though infestations at this late growth
stage are not likely to be economical to treat, it may alert the grower to risk of preharvest losses such as
ear drop or stalk breakage.
Blacklight traps at other locations around the state have caught low
numbers of moths. Corn borer
populations continue to be down across the region. There are still occasional reports of fields with some
light infestations that have shown up in the past ten days.
FLEA BEETLES FEEDING IN CANOLA
Adult flea beetles are emerging from the soil and feeding on green
tissue (e.g., pods, stems) in fields
around the state. In some cases, these populations are very large and feeding is heavy on the upper parts
of the plant. This late feeding seldom causes significant yield reductions because the uppermost pods
where they feed represent a lower percentage of the total yield.
When canola is swathed, the beetles will continue to feed on green
tissue. Most of the time, when
the stubble begins to regrow, the beetles will move to the regrowth and feed on the tender leaf tissue
that is available.
One important thing to note, when large populations of flea beetles
are in fields at swathing time it
should emphasize the need to use seed treatments to protect next years crop. The adult beetles will be
overwintering, becoming active next year when temperatures warm up again.