Grasshoppers and the Plight of Organic Producers

A guest article from SaskOrganics

Deb Tuchelt, Programs Coordinator, SaskOrganics
Myriam Fernandez, Research scientist, Agriculture and Agri-Food Canada, Swift Current Research & Development Centre

Over the last two years, grasshoppers have been wreaking havoc on many parts of the Canadian Prairies. When these voracious pests descend on an area, they can severely damage plants, in some cases devouring crops so thoroughly as to leave previously green fields brown and barren. They have even been known to defoliate neighboring trees or shelterbelts. Add ongoing drought into the mix and the conditions harken back to those experienced by producers in the 1930s. 

Organic grain farmers are particularly disadvantaged against grasshoppers, due to severely limited methods of effective control that are approved for use on organic farms.

SaskOrganics—the member association for the organic producers in Saskatchewan—conducted a survey of our members to better understand and quantify the extent of the issue. The results of the survey showed that grasshoppers are having significant and devastating effects, particularly in the southern regions. In 2023, 21% of respondents projected that between 11 and 20% of their crops would not be able to be harvested due to grasshopper damage. The results indicated that the projected financial loss due in 2023 is more than the actual loss in 2022. For example, 27% of respondents are anticipating that their financial loss will be between $30-90K in 2023, compared to 17% in 2022. At worst, 10% of respondents estimated losses of over $210K in 2023. 

So far, crop insurance has been an important risk-mitigation tool. 

In addition to the crop and financial losses, organic acres have been left vulnerable to wind and water erosion after being stripped clean of vegetation by the grasshoppers, and producers have experienced damaged relationships with neighbors. Twelve respondents considered dropping their certification on some of their land and five producers considered dropping their certification on all of their land as a result of grasshoppers. Two respondents did drop their organic certification on some of their land, and one dropped their organic certification entirely. 

Since the survey, SaskOrganics, Dr. Fernandez and our colleagues, with guidance from the Integrated Pest Management and Insect Management Specialists at the Saskatchewan Ministry of Agriculture, and with the assistance from OMRI, have been researching and reviewing several biopesticides for their potential use. The challenge is that a product has to meet a number of criteria in order to be considered a strong candidate for registration; efficacy needs to be proven by existing data, scientific rationale and/or through the generation of efficacy data through field trials. To qualify for a User Requested Minor Use Label Expansion (URMULE), the product must be registered for use in Canada by the Pest Management Regulatory Agency (PMRA).

In addition to regulatory requirements, the product must also be useful to producers; it needs to be economical and practical to use for large-scale field crop production, be commercially available, and it has to be approved for use by organic certifiers in Canada. In addition, a product’s risk of detrimental effects on non-target species (bees and other beneficial insects) was also taken into consideration.

We reviewed products with the active ingredients Beauveria bassiana strain ANT-03, Spinosad, Metarhizium brunneum (a.k.a. M. anisopliae), pyrethrins, Nosema locustae, diatomaceous earth, and others. Many of the products were ruled out after calculating the cost per acre or the amount of water that would be needed for application. Many biopesticides are suitable for small-scale operations or greenhouse production, but large-scale field application is entirely different. Some didn’t have adequate efficacy data, or there were concerns of harm to other insects. One of the products that has been used in the past with some success and meets many of the other criteria, is unfortunately not commercially available at this time due to manufacturing issues.

High or very high populations of grasshoppers may be present for two to four years, followed by low-to-moderate populations for several years, so this problem is not predicted to go away soon. The conclusions of previous outbreaks were associated with cool, wet conditions. If the current trend of warm, dry springs and summers persists, continued grasshopper pressure is anticipated. Organic producers on the Canadian Prairies are desperate for an effective biopesticide targeting these destructive pests, and are looking to industry to produce a suitable product for their operations. If you are a manufacturer and your company has a product meeting our criteria, please get in touch, at admin@saskorganic.com.

This article originally appeared in the spring 2024 issue of the OMRI Materials Review newsletter.