Blister Beetle Treatment: How to Control and Protect Your Alfalfa

Blister beetle treatment is an important part of growing alfalfa since they may severely affect the quality of crops and the safety of livestock. Proper treatment against the blister beetle prevents the blister beetle damage symptoms, which usually appears as ragged leaf defoliation and, what is more important, the danger of cantharidin toxicity in case infested hay is given to horses or other animals. The implications of such toxicity are also of great economic importance to alfalfa producers since outbreaks can lead to loss of yield, rejection of hay and even death of precious livestock. Due to the stakes, farmers tend to balance the benefits of the old chemical practices with the recent ones, organic ones. Although conventional insecticides are still common in controlling the blister beetles in alfalfa, there is an increased interest in controlling blister beetles using sustainable methods that involve organic biopesticides and biological control methods, particularly using solution such as metarhizium anisopliae insecticide. This blog addresses the distinction between organic and chemical products and provides a preview of the best methods of dealing with these pests, including how to get rid of blister beetles organically. The blog will also explain the blister beetle scientific name and why identification is such a key element of an integrated approach.

Knowing Blister Beetles in Alfalfa

What attracts blister beetles? Multiple species of blister beetles, such as the striped, black, gray (ashgray), and margined blister beetles, may be found in alfalfa fields and each has minor differences in appearance yet can cause damage. Their scientific name is commonly Epicauta, and they are recognizable by their long bodies and relatively narrow necks, and may be either all black or gray, or may have orange stripes. The alfalfa beetles are the most active between May and October when the weather is moderate and the fields are in bloom and swarms are drawn to the fields. Blooming alfalfa and particularly where flowering weeds are present are the most likely to experience high populations due to the fact that flowering plants would be shelter and food to adult beetles. Swarming behavior is characteristic of these insects, which can at times be found in large numbers at the edges of a field where their presence may easily be neglected until harvest.

One of the perilous characteristics about blister beetles is that they produce toxins called cantharidin which causes tissue damage to livestock that ingests even a few beetles in hay. Cantharidin is particularly toxic to horses, and certain species of horse including striped blister beetle are more dangerous. Recent seasons have demonstrated through case studies by the Texas A&M Veterinary Medical Diagnostic Laboratory that beetle contamination in hay is a frequent route of livestock poisoning, and identification, surveillance, and informed pest management are essential to managing blister beetles in alfalfa and to minimize these risks. In the coming parts of this blog, we will explore ways of how to get rid of blister beetles in alfalfa.

Real-World Case Studies and Community Expert Insights

Anecdotal information on agricultural forums frequently feature useful, successful blister beetle treatment, which demonstrates the success of how to treat blister beetles. As an illustration, Iowa State University Extension has reported successful management of blister beetles in alfalfa through manipulation of second and third cutting to prevent optimum activity of the beetles. A Kansas State University study confirms that what kills blister beetles​ is the equipment adjustments (removal of hay crimpers, wide wheel base on swathers) can be used to reduce beetle infestations in bales. An animal safety case at UC Davis veterinary in the recent past supported the risk of feeding goats with blister beetle-infested hay, and clinical symptoms resulted in prompt intervention and adjustments on the local harvesting. In the meantime, Oklahoma State Extension documents border-area treatment success with specific insecticide use and highlights effects of beetle activity during specific seasons. Arkansas Extension also adds that the patterns of crop injury differ depending on the region and that early detection and customized harvesting are also one of the most effective defenses. All these practical examples support the message that the blister beetle control in alfalfa and reduction of the blister beetle damage symptoms cannot be achieved without the active, ecosystem-sensitive farming method, and readiness to change the conditions of work and equipment.

How to Get Rid of Blister Beetles Organically

Myco Pestop, a metarhizium anisopliae insecticide product, is one of the promising solutions to how to get rid of blister beetles organically among organic methods. Metarhizium anisopliae is a soil-based fungus that is a biological control agent since it produces spores that are attached to the outer shell of the beetle. When the spores attach then germinate, infect the body of the beetle, and eventually result in the disease and death of the insect, it takes three to seven days. Since the fungus is insect-specific, it is usually safe to humans, animals, and useful insects with no chemical residues left and promotes environmental safety.

Myco Pestop follicular application pesticide against blistering beetles, can be used by spraying the plant at a rate of 1-2 g/l, drenching or drip irrigation into root zones. The primary advantage of metarhizium anisopliae insecticide is that it would fit well into the organic farming program and other integrated pest management (IPM) system that emphasizes on pest suppression over time, but not the excessive application of heavy pesticides after every now and then. It can also be tank-mixed with other organic treatments (including neem oil), which assists in giving flexibility in rotation and resistance control. The Myco Pestop which are organic pesticides that are blister beetle pesticides are as effective, or even more, effective than chemical controls especially in the long term population control. The effect is anticipated within 1 week and the effect is again checked to ascertain additional efficacy.

Other Organic and Cultural Control Measures

How to get rid of blister beetles in alfalfa? In addition to biological pesticides, cultural control has been one of the major forms of blister beetle control in alfalfa. Diatomaceous earth is a natural mineral powder used in areas of threatened plants or as a barrier where it instantly harms beetles that come in contact with it. Harvesting before the alfalfa is in full bloom, that is, before the main beetle populations are active, can significantly lower the chance of contamination; since it is flowering plants that are preferred by the blister beetles. It is recommended that farmers should not use crimpers and conditioners in processing hay when beetles are alive because these machines have the tendency of crushing beetles and exposing bales to the risk of contamination. Migration of beetles into the crop can be discouraged by treating field borders and fencerows with low-residual pyrethroids. Constant check-ups and early identification are the key factors, which allow spot blister beetle treatment and harvest changes before the number of beetles reaches the critical point. Weed control is also essential and answer to how to control blister beetles: alternative host plants should be eliminated, therefore the general attraction of all beetles to alfalfa fields is reduced.

Prevention and Integrated Management Strategies: Blister Beetle Treatment

An effective prevention strategy to blister beetle control in alfalfa combines ongoing field observation (particularly June-September) with decision-making at each step. Premature harvesting, before alfalfa is at peak flower, may reduce beetle attraction and the possibility of infestation. Further to such a choice, harvesting equipment or settings that reduce beetle mortality, such as the removal of conditioners, will further help reduce the number of beetles in harvested hay. Prior to feeding livestock with hay, checking bales to make sure they are not contaminated with blister beetles in alfalfa safeguards the health of animals and business. In the long run, soil health, conservation of advantageous insects, and integrated systems will offer natural defenses against large-scale pest attacks, eliminating dependence on both chemical and organic inputs and making metarhizium anisopliae insecticide a component of an overall system of how to get rid of blister beetles organically. Now we know that how to get rid of blister beetles organically is not a rocket science. 

Reference:

• Shanley, Ryan P., and Ann E. Hajek. "Environmental contamination with Metarhizium anisopliae from fungal bands for control of the Asian longhorned beetle, Anoplophora glabripennis (Coleoptera: Cerambycidae)." Biocontrol science and technology 18.2 (2008): 109-120.
• Goble, Tarryn A., et al. "Microsclerotia of Metarhizium brunneum F52 applied in hydromulch for control of Asian longhorned beetles (Coleoptera: Cerambycidae)." Journal of Economic Entomology 108.2 (2015): 433-443.