September 2006

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Wash Fresh Fruits And Vegetables Before Eating By Carol Savonen, Oregon State University To keep things safe, you should wash melons and other fruits and vegetables that grow in, on or near the ground in cold water before cutting, peeling or eating them. "There is always a chance for bacteria to grow on the surface of a fruit or vegetable, so washing is important before cutting or peeling your produce, homegrown, or store bought," explained Nellie Oehler, family and community development faculty with the Oregon State University Extension Service. Before cutting into them with a knife, hard fruits and vegetables should be scrubbed with a brush under running water, to rid them of soil particles and possible bacteria, viruses or parasites. To clean soft fruits like tomatoes, plums, apples or nectarines, hold them under running water and rub them all over. Berries should be gently washed in cool water and never soaked. Using detergent to wash produce is a no-no. Oehler cites Cornell University Extension research, which concludes that while washing fruits and vegetables using detergents might remove more bacteria and some pesticides, the soaps may also contain chemicals not intended to be on food. "Once detergent gets into some food it is more difficult to remove than from dishes and it can make people sick," Oehler explained. "In fact, the U.S. Department of Agriculture, the Environmental Protection Agency and the U.S. Food and Drug Administration &endash; the three federal agencies involved in food safety activities &endash; all recommend washing fresh fruits and vegetables with plain water and not with soap or other products." Cornell Extension specialists also say that commercial rinse products that claim to remove all sorts of hazards from produce are not any more beneficial than plain water. They also state that chlorine solutions are no more beneficial than plain, potable water for cleaning produce. "Chlorine may work well to purify clear water or to sanitize clean kitchen surfaces, it does not seem to work well in the complex chemical environment of fruit and vegetable surfaces," they point out in a publication. "Plus, a chlorine solution may leave residues of chlorinated compounds on the produce, and the amounts and safety of such possible residues have not been studied." Those comments are listed in a fact sheet on washing fruits and vegetables. It can be found at: http://counties.cce.cornell.edu/suffolk/FCSprograms/Washing%20Produce.pdf Basically, no washing method completely removes or kills microbes. Oehler says that other studies have shown that bacteria like Salmonella can survive and grow on cut surfaces of tomatoes, cantaloupes, watermelons and honeydew melons. Microorganisms are more likely to survive in the stem scar, growth cracks, and any damaged parts of the produce, so it is important to trim away these parts before serving or eating them. Cut fruit should be refrigerated and not left at room temperature for more than two to three hours. For answers to your questions about food harvest, preservation and storage, the OSU Extension Food Safety/Preservation hotline is in operation from July 17 to Oct. 13. Call 1-800-354-7319, Monday through Friday from 9 a.m. to 4 p.m. (except holidays). OSU Extension Family Food Education volunteers and Extension faculty and staff run the hotline. "Deadhead" Flowers To Neaten Gardens By Davi Richards, Oregon State University Some chores that are tedious for one gardener may seem pleasant to another. Wandering through your garden "deadheading," or removing spent flowers as you go, can be a relaxing way to enjoy your summer's successes while you prolong them. "The botanical purpose of flowers is ultimately to produce seeds so that the plant can propagate itself," explained Linda McMahan, horticulturist with the Oregon State University Extension Service. "When you remove flowers before they start producing seeds, the chemical message to the plant makes it 'think' it needs to produce more flowers." Because plants in nature do just fine without being deadheaded, removing spent blossoms rarely, if ever, is important for the health of the plant, said McMahan. Deadheading makes the most sense for repeat bloomers such as roses and highly modified annuals, such as marigolds, in order to keep them blooming, she said. For most other plants, it is just a matter of appearance and the personal taste of the gardener. There are no special techniques or tools required for this chore. Simply cut or pinch off fading blooms, being sure to remove any seedpods that may have started forming behind the flower. Don't just remove the petals. Keep in mind that one of the aims of deadheading old blossoms is to keep the plant looking attractive. For moderately bushy plants, like marigolds, remove each fading flower and its individual stem. Bushy plants that bloom profusely at the ends of the foliage, like coreopsis, can be sheared back with grass shears. Sometimes this shearing will encourage a new flush of blooming. For plants that produce one flower at the end of a long stem, like black-eyed Susans, cut the whole stem off at the base so you don't end up with empty stems. Some flowers, especially annuals, can be kept blooming through the whole growing season simply by regular deadheading. Marigolds, cosmos and pelargonium (commonly sold as "geranium") are examples of plants that will bloom continually if consistently cutting or pinching off the flowers as they pass their peak. Others, like roses, won't bloom all summer, but they'll bloom longer if they're deadheaded regularly. Some perennials need to be deadheaded to keep them looking tidy, but it won't necessarily make them produce more flowers. The foliage of peony, Siberian iris, and lamb's ear will stay attractive through the season, but won't bloom again after deadheading. Gardeners who want to avoid having "volunteer" or offspring seedlings starting in their flowerbeds may want to do exhaustive deadheading. On the other hand, says McMahan, it can be a great pleasure to watch self-seeders like columbine (Aquilegia) or Shirley poppies come up in delightfully unexpected places. Cosmos and viola both pop up readily the following spring with no effort on a gardener's part, if they're allowed to set seed. "Sometimes the seedlings produce interesting flowers, too," McMahan said, "having worked with the birds and bees to do a little genetic mixing." Before removing every spent flower in sight, be sure you know which plants produce attractive seeds or seed pods that you'll miss if you deadhead everything at the end of the summer. For instance, Gladwin iris (Iris foetidissima) has scarlet-orange seedpods in the fall, and some peonies also produce attractive seeds and seedpods. And of course, the more plants you allow to form seeds, the more likely you'll be to have seed-eating birds visiting your garden regularly. Most Lawns Benefit From Core-Aeration From University of Idaho's HomeWise Think of everything your lawn has done for you and your family this summer: it's cooled your yard, lowered your air-conditioning bills and given your bare feet a comfortable place to play. Now, think about what you can do for it in September. If your lawn is growing in heavy clay soil, if it's become compacted or if it's formed a thatch layer more than a half-inch thick, it will benefit from core-aeration in early fall, says Tom Salaiz, University of Idaho turfgrass specialist. Core-aeration&emdash;removing small soil plugs or cores&emdash;stimulates root growth, improves air and water movement into the soil and provides an ideal environment for seed germination. It also keeps thatch&emdash;a mixture of living and dead roots, shoots, stems and leaves that forms naturally on the soil surface&emdash;to an optimum thickness. Summer is never a good time to core-aerate because the procedure exposes the aerification holes to excessively hot temperatures, Salaiz says. Spring is better, although weeds take advantage of those freshly available growing sites. September is nearly perfect, because roots respond to aeration more readily at cooler temperatures and because the upcoming winter freeze-thaw cycles intensify the aerating effects. Early fall is also an excellent time to overseed should you choose to do so after you core-aerate. To maximize penetration of your hand- or machine-aerator's tines, make sure your soil is moist, but not wet. Dragging the cores with a piece of chain-link fence or running over them with a rotary mower will help break them up and mix them into the lawn. Or, you can just let them wash into the lawn over time. Most home lawns should be core-aerated at least once a year, Salaiz says. Lawns with heavy thatch layers, however, should be core-aerated in the fall and again in the spring. Thatch can reduce soil's water-holding capacity, keep water and nutrients from reaching grass roots, and harbor insects and diseases. "A thick, spongy thatch layer soon becomes the growing medium for grass roots and growth points instead of the soil," says Salaiz. "When this happens, the grass is much more prone to heat and drought stress as well as more susceptible to disease and insect damage." Leaving grass clippings on the lawn does not contribute to thatch buildup, but irrigation, fertilization and mowing practices have an impact. Avoid overfertilizing, watering too little too often and mowing off more than a third of your lawn's height at a time, Salaiz says. Fall Weed Management By Fabian Menalled, MSU Extension Cropland Weed Specialist Fall provides an excellent opportunity for weed control, particularly for perennial broadleaf species. Cooler temperatures trigger the movement of food reserves down to the root systems, enhancing the movement of herbicides to the plant's root system and improving control. Putting into action a few key concepts will enhance your ability to control perennial weeds this coming fall. If plants are stressed from drought or cold temperatures, applications will not provide satisfactory control due to poor movement of the herbicide through the weed. Thus, to secure active translocation, fall herbicides should be applied when temperature are expected to exceed 60-65 Fahrenheit during the day. Fall applications should be made only if plants still have green and pliable leaf tissue. As a rule of thumb, do not expect satisfactory control if less than 60 percent of the original leaf tissue still remains. When estimating the extent of the frost damage, make sure to exclude green brittle leaves. Be aware that perennial weeds vary in their sensitivity to frost and that the application window differs between species. For example, Canada thistle can survive light frosts and is effectively controlled with relatively late fall herbicide applications. Other perennial weeds such as hemp dogbane and common milkweed complete their life cycles by late summer and do not tolerate frost well. Thus, fall herbicide applications should not be delayed when controlling hemp dogbane or common milkweed. Finally, best control of field bindweed is obtained sometime in July at the full flower stage. Although fall application will not guarantee excellent control of field bindweed, late control practices can be quite effective provided there is re-growth of this weed. The following is a summary of control guidelines for several perennial weeds that are problematic in Montana. Canada thistle is one of the most difficult to control perennial weeds as its extensive root system stores large quantities of food reserves. Effective control can only be achieved after these food reserves have been depleted. Glyphosate (Roundup) provides good to very good control when applied at the bud to bloom stage. Banvel and 2,4-D ester can also be applied at the bud stage. Do not till fields infested with Canada thistle as root fragments can produce new shoots. For perennial sowthistle, fall applications of 2,4-D ester or Banvel provide good control when applied at the rosette or bud stage. This thistle is less sensitive to glyphosate than Canada thistle and applications of this product should be made at rosette stage to enhance effectiveness. For field and hedge bindweed, glyphosate and Banvel provide acceptable fall control, but herbicides should be applied only if bindweed is not under drought stress. Due to the lack of excellent control, periodic fall applications should be considered to secure long-term control. Tillage prior to herbicide application is not recommended, because it can stimulate vegetative reproduction due to the increase in the number of buds produced at the nodes of crowns, roots, rhizomes and stems. For prickly lettuce, fall applied glyphosate can be used for control. Unfortunately, prickly lettuce geminates over an extended period in the fall and spring, particularly when temperatures remain warm. Thus, pre-plant spring control may be more effective than fall applications. With common milkweed, glyphosate and Banvel provide fair to good control when applied in the fall at the late bud to flower stage. If possible, pre-harvest applications should be used, because once the combine header cuts down milkweed it will not generate enough foliage for good quality post harvest applications. For dandelion, glyphosate, Banvel and 2,4-D ester are among the several products than can be applied for control in the fall. Dandelions tolerate moderate frost and remain actively growing in late fall (mid September). However, opportunities for post-harvest control are sometime limited by the inadequate weed re-growth. Fall provides a unique opportunity to clean up some troublesome perennial weed problems. To secure success, scout fields for perennial weeds that are still green and growing, make note of their growth stage, select the best product that fits your crop rotation sequence and good luck! Disclosure. Common chemical and trade names are used in this publication for clarity by the reader. Inclusion of a common chemical or trade name does not imply endorsement of that particular product or brand of herbicide and exclusion does not imply non-approval. Contact: Fabian Menalled (406) 994-4783 or menalled@montana.edu Sheep Extravaganza Slated For October 7 From Washington State University A one-day program for adults and youth interested in producing, marketing, and showcasing high quality lamb and lamb products is scheduled for Saturday, October 7, 2006 in Clark Hall on the Washington State University Campus in Pullman. The Sheep Extravaganza program will present the latest information on marketing lamb, pasture and production management, and producing youth livestock projects. The program is sponsored by Washington State University Extension and the WSU Animal Science Department, in cooperation with the Washington State Sheep Producers Association (WSSP). Program participants will be able to choose from one of three separate tracks that meet their educational needs and interests. Track 1 will focus on environmental stewardship, establishing and rehabilitating pastures, fencing options, and sheep health and nutrition. Track 2 will feature an in-depth discussion of processing and marketing lamb and wool products, the National Animal Identification Program, and food safety issues pertaining to lamb. The third track, targeting youth producers and 4-H and FFA parents and leaders, will give participants an overview of the sheep industry, as well the most current information on selecting, feeding and showing market lambs and breeding stock. Each track will feature nationally recognized speakers and industry leaders. The registration fee for the WSU Sheep Extravaganza is $35 for the first participant, and $15 for each additional family, 4-H or FFA member for registrations postmarked by September 20th. The cost increases to $45 for the first participant, and $25 for each additional family, 4-H or FFA member for registrations postmarked after September 20th. The registration feed includes lunch. For additional information on the Sheep Extravaganza, please contact Mark Heitstuman at (509) 243-2009, email: heitstuman@wsu. or Sarah Smith at (509) 754-2011 Ext. 413, Additional information and registration forms are also available on the WSU Central Animal Agriculture web page at http://animalag.wsu.edu under Upcoming Events.

Manage Iron In Drinking Water From University of Idaho's HomeWise At levels normally found in drinking water, dissolved iron is harmless to human health. The U.S. Environmental Protection Agency classifies it as an aesthetic issue&emdash;rather than a health issue&emdash;but too much iron in drinking water can be unhealthy to homeowners' pocketbooks. Besides giving water a disagreeable taste or odor, it can stain laundry and plumbing fixtures, darken vegetables and coffee, and clog water systems, filters and screens. University of Idaho environmental sciences student Alex Colter and soil scientist Bob Mahler have written a publication called "Iron in Drinking Water" that tells homeowners how to test for iron, how to distinguish among four different forms of iron and how to choose among seven treatment options. The first of a series of Pacific Northwest Extension publications on drinking water contaminants, "Iron in Drinking Water" is available at no cost at http://info.ag.uidaho.edu. Web site visitors should first select Catalog, then CALS Publishing Catalog. They can also get a free copy of the publication by calling (208) 885-7982. Iron in Idaho's drinking water either occurs naturally in groundwater or breaks free from iron deposits on corroded pipes. At levels under 0.3 parts per million, it shouldn't prompt household problems, Mahler says. Small concentrations are even essential to human health, because iron helps transport oxygen in the blood. But higher levels can lead to large repair bills when damage builds. Remedies range from $20-100 for screw-on faucet-type water filters to $500-plus for oxidizing filters and to thousands of dollars for well reconstruction. No treatment method works on all four forms of iron, so homeowners should make sure they've diagnosed the problem correctly before shelling out for a cure. Secrets Of Squash & Cucumber Pollination By Carol Savonen, Oregon State University Heat-loving squash and cucumber plants blossom and set fruit in the heat of summer. Fruit set requires successful pollination, which depends a lot on the right timing and location. Most importantly, insects need to carry the pollen from stamens to pistils in most kinds of squash and cucumbers. Most squashes and cucumbers have separate male and female flowers on the same plant, explained Jim Myers, vegetable breeder at Oregon State University. To produce fruit, pollen from male flowers must be transferred to the female flowers. Don't worry if the early blooms on these plants fall off before setting any fruit. Cucumbers and squash often produce many male flowers that bloom and die before the female blossoms appear. How do you tell a male from a female squash or cucumber blossom? The female blossoms have what looks like a tiny squash or cucumber below the flower. The tiny fruit is the ovary, full of eggs not yet fertilized via pollen from male flowers. Male blossoms have long stalked stamens, each with pollen-filled anthers. Every pollen grain contains sperm nuclei, which fertilize the ovules in the female flowers. Visiting bees and other types of insects provide the transportation - when they visit flowers to collect nectar and pollen, bees carry and spread the male pollen from male anthers to female pistils. Each pollen grain grows a long tube down through the pistil, to the egg cells. The sperm nuclei migrate down the tube to the egg, where fertilization takes place. The fertilized eggs, now the seeds, and surrounding ovary will eventually grow into a huge squash or cucumber. Inside, each seed is a tiny plant embryo, the product of the union of an egg and sperm. Be patient with squash and cucumber plants, advised Myers. Eventually, most will produce both male and female flowers. Once blossoms of both sexes are opening, and there is still no fruit formation, there may be poor pollination. Sometimes Mother Nature needs help, if you have a shortage of pollinators. Home gardeners can pollinate the flowers themselves. Use a small watercolor paintbrush and lightly transfer pollen from male flowers to the female flowers. Once fruit develops keep the plants well watered. And don't let cucumbers or summer squash get too big&emdash;their quality may deteriorate. Research in the OSU Department of Horticulture has shown that growing cilantro, yarrow, wild buckwheat, white sweet clover, tansy, sweet fennel, sweet alyssum, spearmint, Queen Anne's lace, hairy vetch, flowering buckwheat, crimson clover, cowpeas, common knotweed and caraway attracts pollinators and other beneficial insects such as natural predators. It's A Compost Pile - Not A Trash Pile By HomeWise, University of Idaho Got fistfuls of weeds bursting with seeds? How about big clumps of quackgrass or thick wads of tangled bindweed? Are you headed to the compost pile? Stop. Weed seeds don't belong in compost piles, nor do weeds like quackgrass or bindweed that spread by roots or by creeping stems or stolons, says Jo Ann Robbins, University of Idaho Extension horticulture educator in Jerome. Composting may not kill weed seeds, stolons or roots, all of which can find new life in your garden next year. "When you spread your compost in the spring, you'll also be spreading weeds," Robbins says. This fall, go easy on adding pine and spruce needles and cones to your compost pile, she advises. "They break down very slowly and are so acidic that they can upset the pH balance of your compost." They're also rich in oils and turpentines that&emdash;in large concentrations&emdash;can kill the beneficial microorganisms that do your pile's heavy lifting by breaking down its plant matter. The citrus oils in citrus rinds can also destroy those same microorganisms. "A few citrus rinds in the pile are okay, but not large amounts," Robbins says. Never compost pet waste, since meat-eating animals can share the same disease and parasites that affect humans. And don't compost fats, whole eggs, meats or dairy products from your kitchen: "They can smell so bad that they attract rodents." Invasion USA - Mexican Truckers On U.S. Roads From 2006 WorldNetDaily.com "A move by the U.S. Department of Transportation to open U.S. roadways to Mexican trucks puts the interest of foreign trade and cheap labor ahead of everything else, including highway safety, homeland security and the well being of hardworking Americans."&emdash;Todd Spencer, Exec. VP, Independent Drivers AssociationTransportation Secretary Maria Cino promises to release plans within months for a one-year, NAFTA pilot program permitting Mexican truckers beyond the limited commercial zone to which they are currently restricted. The program will likely involve about 100 Mexican trucking companies, the Department of Transportation says. Under the North American Free Trade Agreement "NAFTA" the borders were to open partially to truckers from both countries in 1995. Full access was promised by 2000. Because of the restrictions on Mexican trucks, the Mexican government has imposed limits on U.S. truckers. The U.S. restrictions were placed by the Clinton administration in response to demands from the Teamsters union, which said Mexican trucks posed safety and environmental risks. Currently, the U.S. permits Mexican truckers only in commercial zones close to the border that extend no further than 20 miles from Mexico.  While the American Trucking Association supports opening the border, other unions have joined in opposition with the Teamsters. The Owner-Operator Independent Drivers Association came out this month in opposition to any Mexican truck pilot program. Todd Spencer, the association's executive vice president, said the program would jeopardize safety on U.S. roads and would lead to an influx of cheap Mexican labor. "A move by the U.S. Department of Transportation to open U.S. roadways to Mexican trucks puts the interest of foreign trade and cheap labor ahead of everything else, including highway safety, homeland security and the well being of hardworking Americans," Spencer said. In a letter to the Interstate Trade Commission, Spencer wrote: "The net effect of admission of Mexican trucks into the U.S. marketplace would undoubtedly be negative. The supposed benefits to consumers from speculative reductions in shipping rates would be offset by the societal costs that are difficult to measure, but are easy to identify." Spencer told the commission that Mexican trucks are not up to U.S. safety standards, and if U.S. drivers earn less as a result of labor competition, they would have less money to invest in vehicle maintenance, leading to even more less safe trucks. The Teamsters have led opposition to the plan, saying the so-called "NAFTA superhighway," a north-south interstate trade corridor linking Mexico, Canada and the U.S., would mean U.S. truckers replaced by Mexicans, more unsafe rigs on American roads and more drivers relying on drugs for their long hauls. The August issue of Teamster magazine features a cover story on the plan for an enlarged I-35 that will reach north from the drug capital border town of Nuevo Laredo, Mexico, 1,600 miles to Canada through San Antonio, Austin, Dallas, Kansas City, Minneapolis and Duluth, while I-69 originating at the same crossing will shoot north to Michigan and across the Canadian border. Public proposals for the superhighway call for each corridor to be 1,200 feet wide with six lanes devoted to cars, four to trucks, with a rail line and utilities in the middle. Most of the goods will come from new Mexican ports being built on the Pacific Coast, ports being run by Chinese state-controlled shipping companies. WSU At Pike Place Market: The Science Of Food By Denny Fleenor, Washington State University Producing food literally is a science. On Sept. 14, the science behind foods and other Washington products will be showcased at a public reception at Seattle's Pike Place Market, sponsored by Washington State University Extension and the College of Agricultural, Human, and Natural Resource Sciences. The reception will be held from 7 to 9 p.m. on Thursday, Sept. 14, in the Market. The $25 reception will include an abundant variety of Washington's finest farm products, prepared by Seattle chefs, including hearty appetizers with grass fed beef, specialty cheeses and fresh vegetables; fine wines, beers and ciders; and desserts featuring Washington berries. Each course and many displays will highlight partnerships between WSU and community members like farmers, business owners and non-profit representatives. WSU faculty and staff whose research and outreach have contributed to the products and the businesses will be on hand to highlight their connections. Some of the producers and WSU scientists also will be available from 2 p.m. to 4 p.m. at the Market in the organic produce area along Pike Place to talk with the public about the farm/science connection. Elected officials from the area also have been invited to a private reception on Thursday, hosted by WSU King County Extension. It's an opportunity for them to meet Extension staff and become familiar with the array of WSU research and educational resources available to the community through King County Extension programs. The reception will be held at the Pike Pub and Brewery, 1415 First Avenue beginning at 5:30 p.m. (This is not a public event, but media coverage is welcome). The WSU at Pike Place Market events are part of Cougar Week in Seattle that will culminate with the Sept. 16 football game between WSU and Baylor University at Qwest Field. Reservations for the Thursday evening reception can be made by calling 509-335-2243 with credit card information and should be made by Sept. 6. More information about the entire week's events is available at http://www.wsu.edu/seattle/index.html . Common Insecticide Hazardous To Caddis, Researchers Say By Aimee Brown, Oregon State University A common household and agricultural chemical touted for its low toxicity to human and mammal populations may disrupt the life cycles of caddisflies and increase rates of predation on the larvae by other aquatic insects and fish even at doses as minute as 2 parts per billion, according to a study by Oregon State University researchers. Pyrethroids, a class of synthetic pesticides derived from naturally occurring chemicals in chrysanthemums, can enter rivers and streams through a variety of pathways, including run-off from agriculture and home use. Once in a waterway, pyrethroids settle quickly out of the water column, attaching to organic matter and algae in the water and adhering to stones and sediment in the channel's bottom. Caddisfly larvae use this detritus to build hard tubular casings that protect them from their environment and predators. Under normal circumstances the larvae will not leave their casings until they are ready to pupate, however exposure to pyrethroids through case material or ingestion causes a disruption in the nervous system that sends a scrambled signal causing the larvae to perform an early evacuation and leaving them vulnerable. "The larvae are being exposed to a sublethal dose of pyrethroids that results in a behavior ending with death," said Jeffrey Jenkins, a professor in OSU's College of Agricultural Sciences and an Extension Service faculty member. "It's no different than if they would have been killed outright by the chemical. It may be harder to quantitate, but it's still a death sentence." Caddisfly larvae that are not immediately eaten upon their forced evacuation may try to rebuild their casings, but these structures are not the well-ordered tidy domiciles the larvae usually build, said Katherine Johnson, the primary researcher on the project and a graduate student in OSU's Department of Environmental and Molecular Toxicology. Tests conducted by Johnson, Jenkins and Paul Jepson, director of OSU's Integrated Plant Protection Center and a faculty member in the department, found that the post-contamination casings tended to be chaotically constructed, lacking in adequate ventilation and not structurally sound. "Overall, rebuilt casings were 70-90 percent weaker than stream-built cases in our test study," said Johnson. "The insects in the rebuilt cases were extremely vulnerable to predators and more susceptible to predation." In the course of rebuilding, the larvae also use incredible amounts of energy, affecting their overall fitness. These larvae tend to become smaller winged adults and have lower reproductive rates, said Jenkins. "Caddisfly that have been exposed to pyrethroids as larvae are unable to reproduce at the same level as an unaffected population," said Jenkins. "Exposure to this chemical comes down to a decrease in the growth of the population and a decline in overall ecological health." The use of pyrethroids has increased in recent years as businesses and farmers moved away from broad-spectrum organophosphate pesticides because of the environmental and health impacts associated with their use. Today, pyrethroids are one of the most common pesticides used in the home, and are found in products ranging from head lice treatments to lawn fertilizers. "With the synthetic pyrethroids there is much less concern for human health, but the risk to aquatic life is potentially a huge issue," said Jenkins. "These chemicals are considered relatively benign to humans and other mammals, but they have the potential to negatively impact our waterways in a significant manner." According to the U.S. Environmental Protection Agency, pyrethroids are hazardous to both fish and aquatic insects, but concentrations commonly found in rivers and streams are usually too low to cause immediate fatalities in populations. The OSU study was one of the first studies to look at the sublethal affect of pyrethroids on aquatic insects that live in the water. Caddisflies are a food source for trout, salmon and steelhead populations. They are also an indicator of stream health, and an integral part of nutrient cycling, said Jenkins. The larvae have been know to leave their casings when exposed to extreme environmental conditions, including drought, low levels of dissolved oxygen, freezing temperatures and other situations. But the inability to successfully rebuild a new casing is so far unique to pyrethroid exposure, said the researchers. Johnson and other OSU researchers will present their findings at an upcoming American Chemical Society symposium on synthetic pyrethroids Sept. 10-14.

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