INSECT CONTROL

Wheat Midge and Lorsban 4E-SG

There has been a great deal of publicity regarding the orange
wheat blossom midge and its potential impact on the states wheat
crop this coming year. Wheat farmers and ag industry who will be
dealing with wheat midge should become familiar with the biology
of the insect, field scouting, treatment thresholds, and timing
of treatments. Not every acre of wheat will require treatment in
the state. However, with delayed planting looking like a real
probability, fields planted in the last half of May will be at
greatest risk.

The product currently labeled and recommended for wheat midge
control is Lorsban 4E-SG. This product is labeled as a special
local needs, 24(c), label for the state of North Dakota. The
product is a RESTRICTED USE product and can be applied only by
certified applicators. The product is an organophosphate (OP)
insecticide, making it a cholinesterase inhibitor. The signal
word on the label is: WARNING. The oral LD50 for rats is 96 to
270 mg/kg. The action of the OP cholinesterase inhibitor is such
that recovery to normal cholinesterase levels can be relatively
slow. When repeated exposures to the product occur, the effects
can become more apparent over time. Symptoms of OP poisoning
include: muscular twitching, muscular weakness, urination,
defecation, and lacrimation (tearing). Severe symptoms include:
convulsions and prostration.

Care will be necessary for applicators who may be using the
product extensively within a very short time, perhaps about 10
days. The label states that the personal protective equipment
(PPE) required by applicators and handlers includes: long-sleeved
shirts, chemical-resistant gloves, shoes plus socks, protective
eyewear. Clothing and other absorbent materials that have been
contaminated with the product concentrate should be discarded.
Users should wash hands before eating, drinking, chewing gum,
using tobacco or using the toilet. Remove clothing immediately if
product gets inside. Wash the outside of gloves before removing.
As soon as possible, wash thoroughly and change into clean
clothing.

Applicators should not take the PPE items used during mixing and
loading with them into the protective cab or cockpit. This will
only increase the risk of inhalation exposure. Take care to
minimize exposure to the product during all handling and
application phases. 

With the increased risk of needing to use this product in the
upcoming season, all applicators should become familiar with
safety measures needed to handle this product carefully. Good
stewardship on your part will demonstrate to the general public
your ability to handle this product safely. 

(Submitted by Phillip Glogoza, Extension Entomologist)