Posts Tagged: Corn
If you like corn, you should be concerned about a pest that's known as "the billion-dollar beetle." The Western corn rootworm is called...
This image by Keith Waldron shows rootworm damage. The corn rootworm is a billion-dollar pest.
Rootworm larvae. (Image courtesy of Wikipedia Creative Commons)
The Western corn rootworm ravages cornfields across the nation. This image was taken in Franklin, Pa. (Photo by Fishhawk of Flickr, Creative Commons)
As the alfalfa hay harvest season wraps up and we get in gear to attend the November 2017 Western Alfalfa and Forage Symposium in Reno, NV, we're...
Corn silage producers can get 'more crop per drop" with deficit irrigation, however productivity will decline, reported Dennis Pollock in Western Farm Press. Pollack based the story on a seminar at the World Ag Expo earlier this month presented by Mark Lundy, UC Agriculture and Natural Resources Cooperative Extension advisor for Colusa, Sutter and Yuba counties.
Lundy said there are certain times in the crop's development that farmers will not want to stress the corn silage - when tassels and silk are forming. At other times in its development, even if the corn is stressed, the application of more water does not bring a proportionate increase in yield.
The UC ANR advisor suggested farmers choose planting dates, varieties and cultural practices that will maximize irrigation efficiency.
“Look at what you choose to grow and perhaps plant later with a short variety or drought tolerant variety,” he said. “And get weeds under control. They take up water.”
Mark your calendar for Thursday September 5th and plan to join fellow growers, PCAs, and seed and chemical company reps at our annual Alfalfa and...
My genealogical roots deep run through many a corn field since I was born from a Nebraska-farm girl mother and an Indiana-raised father. Field corn. Popcorn. Sweet corn. You name the corn, my relatives planted it. Several decades back I even grew ornamental corn one summer to decorate Christmas wreaths. So needless to say I was riveted to a recent Wall Street Journal article about how Mother Nature is outsmarting genetically modified corn seed. (Ian Berry, “Pesticides Make a Comeback”, Wall Street Journal, May 22, 2013, p. B-1.)
Seems that entomologists at the University of Illinois and Iowa State University found corn rootworms immune to Monsanto’s Bt (Bacillus thuringiensis) gene. That gene was originally designed to shield corn crops from this pest that feeds on leaves, tassels and silks; injures roots and can stunt or kill young shoots and plants.
The article also points out that last year America’s farmers planted 97 million acres in corn based on increasing prices and EPA approval touting reduced insecticide use that would give growers and farm workers “greater safety, protect water bodies from runoff and mitigate” harm to wildlife.
“Some of those gains are quickly being reversed,” said Michael Gray, a UI entomologist quoted in the story, who went on to say that next year over a quarter of corn farms plan to use insecticides as “cheap insurance.”
Makes senses now why sales are up for pesticide producers. To read the entire article, log on to WSJ online or review a similar story “Pesticides make a comeback against Monsanto seed” at
Frankly, I wanted to know exactly what this crawly critter chomping on corn crops looked like. During my research of “corn rootworms,” I discovered crop damage is not limited to larvae but includes the adult — two familiar beetles often found in our own backyard vegetable patch that also feeds on cucurbits, legumes and grasses — the Western striped cucumber beetle (Acalymma trivittatum) and the Western spotted cucumber beetle (Diabrotica undecimpunctata undecimpunctata). (See UC IPM Pest Management Guidelines: Corn, plus UC ANR Publication 3443. Also UC IPM Pest Management Guidelines: Curcurbits, plus UC ANR Publication 3445.)
Photos below are of the Western striped cucumber beetle and the Western spotted cucumber beetle).
And there’s more. In fact, there’s also a banded cucumber beetle (Diabrotica balteata) and a spotted cucumber beetle (Diabrotica undecimpunctata howardi), also known as the Southern corn rootworm. In addition, there’s the Northern corn rootworm (Diabrotica barberi Smith & Lawrence), and the Western corn rootworm (Diabrotica virgifera virgifera LeConte).
When you compare the above two photos with photographs on Purdue University’s IPM website, you’ll notice that our Western spotted cucumber beetle looks identical to the Southern corn rootworm and that our Western stripped cucumber beetle appears the same or similar to the female Western corn rootworm. Plus, there’s a photo of the larvae -- the actual rootworm. Here’s the Purdue IPM link: