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were also published that week in the weekly newsletter Scaffolds put out by Dr. Art Agnello, entomologist at Cornell Uni- versity, New York. Some of the neonicotinoids are highly toxic to honeybees, but there are several of them and they are not all equally toxic, Biddinger said. The major concern is that they are systemic, meaning they are taken up by the plants and circulate within the plants. While that provides a lethal deter- rence to chewing and sucking pests, it can also be present in pollen and nectar, which makes them a problem for pollina- tors beyond their direct contact toxicity, he said. One of the studies this spring, by Uni- versity of Maryland entomologist Dr. Galen Dively, reported negative effects on bees visiting pumpkin flowers where soil had been treated with a neonicotinoid insecticide. This can be a serious prob- lem, vanEngelsdorp said, since pumpkins and some other vegetables, like squash and cucumbers, bloom over a long period, unlike fruit crops. Neonicotinoids can persist in soil for months or even years after a single appli- cation, Biddinger reported in his white paper. Measurable amounts of residues were found in woody plants up to six years after application, but, so far, these have only appeared in plants where non- foliar applications were made at much higher rates then normally used in orchards. Biddinger expressed concern about neonicotinoid products approved for homeowner use in gardens, lawns, and on ornamental trees. Recommended rates there can be 120 times those used in agri- cultural crops, he said. Contamination One of the studies this spring focused on their use as seed protectants and the resulting contamination of nearby flower- ing plants exposed to the talcum powder dust used to carry the insecticide in the seed boxes. Millions of acres of corn are planted using neonicotinoid-treated seed. Biddinger notes that the neonicoti- noids, unlike other insecticides, seem more toxic to bees by ingestion than by contact. Dinotefuran, imidacloprid, clothianidin, and thiamethoxam are rated as highly toxic to bees, acetamiprid and thiacloprid as moderately toxic. In addition to death, bees can suffer sublethal effects that impair foraging and feeding behaviors, learning, navigation, and mobility. It is very difficult to study the interactions and understand what happens in a farm setting, Biddinger said. He also reminded everyone to not the throw the baby out with the bath water. Neonicotinoids came into wide use because they have great benefits in IPM programs, are very kind to predatory mites, are effective at very low rates, and are less toxic to people. Biddinger's full report can be found online at www.xerces.org/wp-content/ uploads/2012/03/Are-Neonicotinoids- Killing-Bees_Xerces-Society1.pdf. The same week that the Xerces report on neonicotinoids was released, another publication was released from the North- east IPM Center specifically on wild polli- nators for eastern tree fruit growers. A joint publication by Cornell University, Penn State University, and the Xerces Society, this 18-page color brochure is available online at www.northeastipm. org/park2012 and offers conservation advice to fruit growers relying on native pollinators. It identifies with photos most of the important types of bees found in New York and Pennsylvania apple orchards, and contains a bee toxicity rat- ing table of the most commonly used insecticides, fungicides, and fruit thinners. • 10 MAY 15, 2012 GOOD FRUIT GROWER www.goodfruit.com