Southwest Yard & Garden – Is There Anything Grasshoppers Won’t Eat?
This colorful rainbow grasshopper (Dactylotum bicolor) can be easy to find in desert grassland areas, but is not considered to be an economically important pest in our region. Photo credit Alan Levine (Wikimedia Commons).
A few people have recently reported what appears to be grasshopper damage on a variety of landscape and garden plants. The telltale signs are 1) ragged, chewed holes in leaves, stems, and fruit, and 2) droppings (aka frass, insect excrement) that look kind of like little black ants without legs. Please note that circular, smooth holes on the edges of leaves are more likely to have been made by leaf-cutter bees, and are a welcome sign in my garden!
“A Manual of the Grasshoppers of New Mexico” is a great NMSU online tool for all things grasshopper that includes ecology, economics, and a history of these interesting pests in New Mexico (https://aces.nmsu.edu/academics/hoppers). Also included are species descriptions, distribution maps, and photos.
For more links to helpful info on pesky and beneficial insects, visit the blog version of this column at https://nmsudesertblooms.blogspot.com/2021/06/hoppers.html.
The following is a reprinted column by Dr. Curtis Smith from August 24, 2002.
Question: I have always wondered about the grasshoppers that attack my garden most years. Is there anything I can plant that they won’t eat?
Answer: Dr. Carol Sutherland, NMSU Extension Entomologist [retired in 2021], told me that there is a grasshopper to eat any plant you may grow. Not all grasshoppers eat all plants; some are very specific, while others are not picky eaters at all.
She says that there are at least 160 described species in New Mexico (implying that there may be even others yet to be discovered and described). A couple of these prefer to eat weeds and could be considered beneficial. Of the remainder, about 40 species have the potential to become major pests. Some of these prefer grasses, others broadleaf plants, and some both. The extent of the problems we have in our landscapes depends on which species are present (usually more than one), how many of them are present, and what they prefer to eat. I find the following statement from Dr. Sutherland very informative. “Short of rebar, steel, aluminum, adobe, rock, asphalt, and concrete, I can’t think of many substances that will be little damaged consistently by grasshoppers of one kind or another.” So, in one year we may have fewer problems; in another year, we may have more problems.
Dr. Sutherland also explained that the weather affects the numbers of grasshoppers. Drought, especially in the early spring, can greatly reduce the grasshopper population, and thus the damage done by grasshoppers. When we irrigate, we help the grasshoppers avoid the spring drought dilemma. Careful and limited irrigation of landscapes may help, but the river valleys are also escape valves for grasshoppers. If they can make it to the valleys, they will survive and be able to migrate to our gardens.
There are chemicals to use, but their effect is limited by the fact that grasshoppers are migratory. Adult grasshoppers have wings and can fly into our gardens. So, after we kill some, new grasshoppers arrive to continue eating our garden plants. Some people prefer the insect diseases that can be purchased as biological control for grasshoppers. These are effective with some species, but not all species. Some gardeners claim great success using guinea fowl, turkeys, and other birds that eat grasshoppers. Unfortunately, some birds (biological grasshopper control agents) also eat garden plants.
Grasshoppers are a difficult problem for gardeners in our area. For the very adventurous gardeners, Dr. Sutherland states that grasshoppers are edible and highly nutritious. I think that is good information for the guinea fowl (I am not yet ready to eat grasshoppers).
Extra note from Marisa: A friend once made “hopper poppers” by stuffing jalapeños with grasshoppers and cheese before roasting them. If you try them, please post pics on social media and tag me (@NMDesertBlooms).
For more gardening information, visit the NMSU Extension Horticulture page at Desert Blooms and the NMSU Horticulture Publications page. Find your local Cooperative Extension Office at https://aces.nmsu.edu/county/.
Dr. Marisa Y. Thompson, Ph.D., is the Extension Urban Horticulture Specialist in the Department of Extension Plant Sciences and is based at the New Mexico State University Agricultural Science Center at Los Lunas.