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Show THE OGDEN VALLEY NEWS Page 4 Volume II, Issue IX 1 May 2000 Aid for Suppressing Grasshopper and Mormon Cricket Infestations Compiled by Shanna Francis Ogden Valley News Staff Grasshoppers, locust, and Mormon cricket infestations within the state are running rampant. A biological insecticide, registered with the Environmental Protection Agency, called NOLO BAIT is available to help farmers and other property owners combat the damage that can be caused by these western pests. NOLO BAIT, unlike chemicallybased insecticides, contains a naturally-occurring spore called Nosema locaustae that infects grasshoppers. The disease that results from this infection is activated once the spore is ingested by the grasshopper. Infection and sickness to the grasshoppers from this insect pathogen begins upon ingestion of the bait by the grasshopper. Grasshopper death will begin in three to six weeks. The insect pathogen multiplies in infected grasshoppers and will pass from grasshopper to grasshopper and can remain active for several years. The infection is lethal to 58 species of grasshoppers, locusts, and some species of crickets. In essence, when a grasshopper consumes the spores, it is like giving them the flu or giardia. NOLO BAIT is a suppression bait made from flaky wheat bran that is sprayed with the Nosema spores. It is non-toxic to humans, livestock, wild animals, birds, fish, non-target insects, other life forms other than grasshoppers, or water resources. NOLO BAIT has no restrictions around bodies of water and can be used up to the water’s edge, as directed by EPA regulations. As a grasshopper or cricket suppression tool, NOLO BAIT does not work rapidly. It is a subtle disease that is naturally occurring and takes time to develop to levels that can be readily identified. By putting out the bait at the minimum label rate of 1 lb. per acre equivalent, you are performing what is called an “inoculative” release. This will begin the disease process in the population present at that time; however, depending on the grasshopper population densities and varying age groups at the time, the level of inoculation will vary. Heavier concentrations of the bait may be necessary depending upon concentration of grasshoppers. For instance, if you have more than eight (8) grasshoppers per square yard and put out one pound to the acre one time, you will probably have serious competition for each flake of bran among the grasshopper population. Quite possibly there will be a large percentage of hoppers that don’t even get one flake to themselves. In this case, there will be many that will not become infected, at least until they begin consuming those grasshoppers around them that have become sick enough to become attractive as a food source to the healthy grasshoppers–grasshoppers are cannibalistic–thereby spreading the disease. Because grasshoppers are extremely migratory and can move over great distances, it is optimal, if within economics, to inoculate your area frequently throughout the season. This will help to spread the infection further and aid in long term control. NOLO 801-745-4000 2555 WOLF CREEK DRIVE EDEN, UTAH STORE HOURS: MON. - SAT. 7 AM - 10 PM SUNDAY 7 AM - 9 PM *Coupon* 8-piece Chicken Dinner $2.99 w/coupon $4.99 without coupon Limit 1 coupon per purchase Expires 5/20/00 *Coupon* Dreyers Old-Fashioned Ice Cream $2.49 with coupon $3.49 without coupon Limit 2 per coupon Expires 5/20/00 BAIT may not work as quickly as some would like, but used correctly, it will have a noticeable impact on populations in the long term. Due to the nature of the disease, the effects will vary according to age and species of the grasshopper, and the amount of spores that the grasshopper was able to consume. In very young, newly hatched grasshoppers, death may occur within a week. Unfortunately, if you are not planning follow up treatments, this may not really be the optimal time to infect, simply because it does not offer long term carryover. The young hoppers die quickly and dry up and disappear. Healthy grasshoppers migrate in, making it difficult to notice an impact. By the time grasshoppers reach the third state of growth, or a one-half inch length, they have developed enough body mass to allow the spores to reproduce to some extent. They will become lethargic and dramatically slow or quit feeding, but will not die immediately. This stage allows for some spreading of the disease to take place as healthy grasshoppers come in and consume them. Once grasshoppers are almost to adulthood, infection results in the loss of appetite, lethargy, increased spore production inside their bodies and therefore more spread of the disease. It is actually good to see them very slowly moving about and yet not feeding because it is only in these lethargic but living grasshoppers that the disease can continue to propagate and eventually spread to more of the population. In young adults, reproduction and egg laying may be severely depleted or even stopped. When reproduction does take place, quite often the spores will be passed on in the sticky substance that surrounds the egg pods. Young will become infected as they chew their way out of the egg pod and crawl up through the soil to the surface after hatching. In this case they will probably not survive their first molt. This process explains why you may observe more obvious results the season after application has taken place then during the season in which you inoculated. This is due to an overall decrease in egg laying capability, and infection of the new spring hatch. Follow-up applications each year grasshopper populations are on the increase are useful to continue this process. Winter and spring weather will also have an effect on the spring hatch, as will the cycle the population is in at the time. Grasshopper cycles peak and valley approximately every seven years. This can vary by one to two years either way, but basically, every seven years or so, they will hit an all time high or an all time low. It is helpful to check with the Department of Agriculture in your state to find out what the population predictions are for your area on a year-by-year basis. Obviously, in Utah, we are currently experiencing and upswing in cricket and grasshopper populations. You can plan your releases of NOLO BAIT accordingly. If populations are in the uphill trend, it is definitely advisable to begin the disease process immediately and to continue to innoculate each year until the peak has happened and the downward cycle becomes evident. If you get started soon enough and a large enough percentage of grasshoppers are inoculated, you may deter severely escalating populations from ever actually taking place. The more area treated on a consistent basis, the more long term control you can expect to take place. Optimally, spreading bait frequently throughout the season will be more advantageous than just once at the label minimum application rate of one pound for each acre. How does Nolo Bait work? A grass hopper ingests one flake of the bran formulation and becomes infected. The spore is activated once it reaches the mid-gut of the grasshopper, germinating like a seed after planting. The subsequent infection of the grasshopper’s vital system can ultimately cause death. While infected and sick, the insect eats less and less, thus reducing loss of vegetation. In a period of three BAIT cont. on Page 5 |