Glendon Philbrick, an experienced organic farmer in North Dakota, is known for his innovative approach to sustainable farming practices. With over 200 acres of certified organic land, he has consistently focused on diverse cropping, seed saving, and soil stewardship. Recently, Philbrick began exploring ways to deter grasshoppers without using chemicals. With support from a SARE Farmer Rancher grant, he investigated whether increasing a plant's Brix level (sugar content) could make crops less appealing to these persistent pests.
"Grasshoppers have plagued North America many times," said Philbrick. "Through observation and testing with a refractometer, one can assess that grasshoppers dislike and avoid plants with high Brix levels. This project aimed to test methods for raising Brix levels in several crops, including commodity crops, vegetables, and flowers, through various methods as a means to not only stop grasshoppers from destroying crops, but also improve soil health."
Brix
Brix is a scale used to measure the sugar content in liquids like plant sap, fruit juice, or wine. It’s expressed as a percentage, so a Brix reading of 12% means there are 12 grams of sugar in 100 grams of liquid. Some farmers have observed that insects, like grasshoppers, avoid plants with higher Brix.
Testing the Brix Hypothesis
In 2023 and 2024, Philbrick conducted trials using Brix-raising treatments on various crops, including alfalfa, soybeans, oats, tomatoes, and lettuce. Each treatment involved the application of OMRI-approved inputs, such as calcium, humic acid, amino acids, or adjustments to the potassium-to-nitrogen ratios. Brix levels were monitored weekly with a refractometer, and grasshopper damage was recorded throughout the season. Glendon's objective was to achieve a Brix level of 12%, a threshold believed to enhance plants' resistance to pests.
In his experiments measuring Brix levels, Philbrick discovered that certain soil amendments can effectively increase the sugar content in plants, which is essential for deterring grasshoppers. He noted that the application of calcium significantly raised Brix levels in crops like carrots and tomatoes. Additionally, treatments with humic acid led to notable improvements in lettuce and oats. By adjusting nutrient availability based on soil tests—particularly by addressing deficiencies in potassium, calcium, and micronutrients—Philbrick was able to enhance Brix levels without negatively impacting crop yields. His findings suggest that these amendments can provide an organic method for reducing grasshopper pressure.
next steps
One of Philbrick's key insights is the significance of biology in plant health and how appropriate soil amendments can enhance it. He plans to continue his experiments and encourages other farmers to regularly monitor Brix levels to mitigate grasshoppers, particularly after drought years. Philbrick's next step is to test soil biology directly and explore how various amendments might work together.
About Farmer Rancher Grants
NCR-SARE’s Farmer Rancher Grant program starts accepting proposals in mid-August.
View Related SARE Grant:
- Brix Levels For Grasshopper Control (FNC23-1389)