By Scout Nelson
Recent weather patterns in Nebraska have created conditions conducive to grasshopper outbreaks, as indicated by the fall grasshopper survey. This survey found significant grasshopper populations in 15 counties, signaling potential issues for the upcoming summer.
Grasshoppers pose a greater threat in areas of Nebraska that receive less than 30 inches of annual rainfall, covering the western two-thirds of the state.
The presence of drought conditions over several consecutive years further exacerbates the risk of outbreaks, particularly in the southwestern, southcentral, and western regions which have seen below-normal precipitation.
Nebraska is home to around 50 grasshopper species on rangeland, but fewer than 10 typically reach levels that cause significant economic damage. These grasshoppers damage vegetation primarily through direct feeding on leaves and stems, and their high daily consumption rates can severely impact forage availability.
Grasshoppers overwinter as eggs, which hatch when ground temperatures rise between 50° to 55° Fahrenheit. Nymphs, resembling miniature adults without fully developed wings or reproductive organs, undergo several molts as they mature—usually five on average. Their development is influenced by temperature and the quality of available food.
To determine grasshopper density, experts recommend the square foot method, which involves counting grasshoppers within a visualized square foot as one walks towards a point. This method suggests counting in 18 different locations to estimate the density per square yard.
For those seeking assistance with grasshopper control, David Nielsen at USDA-APHIS can be contacted for technical support at (402) 434-2348 or by email at David.Nielsen@usda.gov.
The Reduced Agent and Area Treatment (RAATs) method, developed at the University of Wyoming, effectively controls grasshoppers by applying insecticides in alternating strips.
This method cuts application costs significantly and reduces environmental impact.
When applying insecticides like Dimilin® 2L and Prevathon®, it is crucial to target when grasshoppers are in their early nymph stages to maximize effectiveness.
Understanding and addressing the life cycle and habits of grasshoppers are essential for protecting Nebraska's agricultural lands from potential devastation by these pests.
Photo Credit -pexels-tudsaput-eusawas
Categories: Nebraska, Crops