Cancellation of Effective Insecticides Puts Carrots at Risk of Rejection by Food Companies

The carrot weevil is native to northeastern North America. Each female can lay 300 eggs. After hatching and entering the carrot, the larvae tunnel through the carrot, filling the tunnels with excreta. The epidermal cells around the tunnels die and become dark brown. The presence of larvae, excreta and feeding damage are of major concern to carrot processors because of strict FDA quality control in processed foods. Processors are unwilling to accept carrots if they find one live larva in a sample or if the carrots have more than 1% damage. Since the 1940s, effective broad spectrum insecticides kept carrot weevil damage to a minimum; however, the most effective insecticides have been cancelled for use in the US.

“Adults [carrot weevils] overwinter in and near carrot fields where carrots were grown the previous year, emerging in late April to early May in New Jersey. The adults feed directly on the leaves and crowns of carrots, and females oviposit from the beginning of May until late June in carrot roots. Larvae tunnel extensively throughout the upper third of the roots, damaging 80% or more of the carrots in untreated processing carrot fields.”

“Consequently, pesticide applications are directed at adult weevils to prevent or reduce oviposition. … However, during the past several years, carrot weevil damage has been increasing in New Jersey carrot farms, and the damage has been as high as 90% loss on farms in Salem County. These losses are partly due to the cancellation of broad-spectrum insecticides, such as parathion, azinphos-methyl, and phosmet during the early 1990s.”

Authors: G.M. Ghidiu¹, E. Hitchner², M. Zimmerman¹ and E. Rossell¹
Affiliations: ¹Rutgers University; ²Virginia Tech
Title: Effect of two different nozzle arrangements on control of carrot weevil, Listronotus oregonensis (LeConte), in processing carrots.
Publication: Plant Health Progress. April 3, 2006.

“Organic Blueberries Don’t Come Easily”

The New York Times ran an article with this title in 2011 to inform readers why there are so few organic blueberries grown in New Jersey – “the blueberry capital of the world”. It seems that the organic blueberry growers are powerless to prevent massive feeding on their berries by insects that call New Jersey home. On the other hand, blueberry growers who use chemical insecticides are able to control the insect problem and harvest 2 to 4 times more blueberries per acre.

“New Jersey is one of the country’s top producers of blueberries, yet only a small number of farms are organic. And considering all the obstacles presented by nature, it’s not hard to see why. Insects like the root grub and the plum curculio, as well as some fungi, contribute to organic farmers’ loss of up to 50 percent of their berries a season, whereas conventional farmers may lose 5 percent or 6 percent, said Peter Oudemans, a Rutgers professor and a plant pathologist at the Philip E. Marucci Center for Blueberry and Cranberry Research in Chatsworth, Burlington County. Blueberry plants are native to New Jersey, Dr. Oudemans said, which makes them a natural food choice for native insects. ‘Planting a solid acre of organic blueberries in New Jersey is like throwing a peanut butter sandwich into a room full of kindergartners,’ said Dr. Oudemans, of Hammonton, ‘the blueberry capitol of the world,’ according to a local highway sign. ‘Everything around is going to go for them.'”

“‘We have to do twice the work of conventional growers,’ Mr. Condo [an organic grower] said. ‘It’s a lot harder and much more labor-intensive. Conventional farmers probably get around two or three thousand crates per acre. We’re lucky if we get 700 to 900.'”

Authors: Tammy La Gorce
Title: Organic blueberries don’t come easily.
Publication: The New York Times. June 17, 2011.