August 2004

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Kochia Management: Reducing The Risk Of Carryover And Crop Injury By Fabian Menalled, MSU Extension Service Cropland Weed Specialist Kochia is a troublesome annual weed in the Great Plain's dryland cropping systems. It was introduced to North America from Europe and Asia in the 1890s as an ornamental plant, and now is present in every county in Montana. It heavily infests 200,000 acres of the eastern Golden Triangle. Kochia is very difficult to control because it can emerge at any time during the winter or growing season with later seedlings emerging after post-emergence herbicides have been applied. Mature kochia plants are very competitive as they are exceptionally drought tolerant and can grow under a wide range of soil pH and salt concentration. Kochia plants produce many thousands of seeds that, because of its tumbling behavior, are dispersed though long distances. Luckily, these do not stay viable in the seed-bank for long with more than 90 percent of them dying within a year. Many kochia populations have developed herbicide resistance. In 1989, and after several years of continuous use of ALS inhibitor herbicides, herbicide resistant kochia biotypes were detected infesting Montana croplands. These biotypes can be found in most Montana cropland, are highly resistant to Glean (chlorsulfuron) and Ally (metsulfuron-methyl) and may be cross-resistant to other ALS inhibitors herbicides. In 1984, kochia populations that had evolved resistance to Photosystem II inhibitors such as atrazine were detected in Montana croplands. Research has shown that these resistant biotypes may be cross-resistant to other herbicides with the same mode of action. In 1995 kochia biotypes with moderate resistant to synthetic auxins herbicides including Banvel, Clarity (dicamba) and Starane (fluroxypyr) were detected in Montana croplands (Source: International Survey of Herbicide Resistant Weeds. http://www.weedscience.org.) Montana's producers have recently added Spartan (sulfentrazone) to their farming toolbox as a way to manage problematic weeds including kochia, Russian thistle, buckwheat, common lambsquarter and pigweed. Because Spartan is a PPO-inhibiting herbicide, it can be used to control resistant kochia plants. Specifically it inhibits the synthesis of a precursor of chlorophyll, causing rapid destruction of contacted tissue. Though Spartan has foliar activity, its main use is as a selective soil applied herbicide that can be applied as a preplant incorporated or pre-emergence (to weed and crop) treatment. Soil pH, organic matter content and soil type play a very important role in determining the availability of Spartan in the soil solution. As a general rule, as soil pH increases, Spartan availability increases. Also, because Spartan is adsorbed to the clay and organic matter fraction of the soil, higher rates may be needed on soils with high organic matter and fine texture. Finally, irrigation with alkaline water (pH greater than 7.5) can increase the availability of Spartan in the soil. Spartan is stable in soil with a half-life of 18 months. Because of its relatively long persistence, it is very important to consider the rotational restrictions following Spartan application. For example, the minimum interval after Spartan application is four months for wheat, barley, rye and triticale, 12 months for alfalfa and cereal grains such as buckwheat, oat, and proso millet, 24 months for canola, and 36 months for sugar beets. It is recommended to conduct a bioassay prior to planting to determine crop sensitivity to Spartan. Recent studies done at Montana State University showed that Spartan does an excellent job on kochia and many broadleaf weeds and it can be tank mixed with Roundup (glyphosate). Moreover, post harvest applications of Spartan have sufficient residual activity to control kochia seedlings the following spring. More information on specific rates and tank mixtures can be found in Post-harvest Kochia Management in Small Grains (MontGuide fact sheet #200213/Agriculture from the Montana State University Extension Service, available through the Montana State University Extension Service or at http://www.montana.edu/wwwpb/pubs/mt200213.html.) Unfortunately, farmers at several locations have reported severe wheat injury due to Spartan carryover. Researchers at MSU have also detected barley and dry pea injury after Spartan applications. We do not know why Spartan injures crops in some locations but not in others but we suspect it is due to a combination of soil factors, climate conditions, and seeding depth. Specifically, the risk of carryover injury appears to be higher in areas where soils have high pH (7.8 &endash; 8.1) and low organic matter (less than 1.5 percent). Research conducted at Iowa State University indicated that crop injury with Spartan can happen when heavy rains occur as crops are breaking through the soil surface splashing high concentrations of herbicide onto hypocotyls, cotyledons and growing points. While there will always be a potential for crop injury with herbicides, good management can minimize this risk. For example crop injury due to Spartan splashing on emerging crops can be reduced by a few management strategies. For example, you could check with your seed supplier to determine the sensitivity of varieties to Spartan prior to purchasing seed. Also, you could increase the likelihood that the herbicide will be moved into the soil profile by rain by spraying one to two weeks prior to planting. Finally, the potential for injury is greater on poorly drained soils where puddling and splashing may occur with heavy rain. Producers know that losing a crop due to lack of rain or hail is an unfortunate but inevitable experience that could have dramatic financial consequences. Losing a crop due to herbicide injury could be as bad as a weather calamity. However, if precautions are taken, herbicide damage can be avoided. To achieve this goal, producers should shift emphasis from considering herbicide benefits on the current season to understanding the mid- and long-term consequences of their management practices. In doing so, farmers should consider the integration of multiple control practices aimed at reducing weeds abundance and avoiding herbicide carryover, crop injury and development of herbicide resistance. 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. Send Pavement Ants To A Watery Grave From University of Idaho's HomeWise Great news! Those ants building mounds in the cracks of your driveway don't have designs on your sugar bowl Ed Bechinski, University of Idaho Extension integrated pest management specialist, estimates that a couple hundred different kinds of ants occur in Idaho. Among these are representatives of a group entomologists call "pavement ants." Pavement ants "rarely become problems inside the house," Bechinski says. "They're general scavengers, feeding on weed seeds and the carcasses of other insects and spiders. We've created an ideal habitat for them under our driveways, sidewalks and flagstones. We've given them a very protected habitat." To build their underground nests, pavement ants move particles of sand and soil out of the way, heaping them in places that we can see. Although they'll move loam and clay particles, Bechinski says sand particles are easiest for them to transport. To control pavement ants, he advises wetting down their mounds every day until you flood out the colonies. "The ants won't be able to withstand the moisture," Bechinski says. "They won't pick up and move somewhere else. They'll just die." He doesn't advise replacing your flagstones with other landscape surfaces just to avoid ants. "No matter what you do, you'll create an ideal habitat for some pest you don't like," he says. "If you take action against one pest, you'll create a habitat that's just right for another." Field Bindweed Can Be A Gardener's Nightmare By Carol Savonen, Oregon State University There's no weed more frustrating to home gardeners than bindweed. Known to weed scientists as "field bindweed," (Latin name: Convolvulus arvensis) this deep-rooted perennial is in the morning glory family (Convolvulaceae). Field bindweed spreads by seed and a deep, extensive root system. Scientists have reported that seed from bindweed can persist in soil for up to 60 years and its roots can grow up to 30 feet deep. It is obvious why this plant is such a problem. What's a poor gardener to do? Here are some strategies to help curb this botanical monster from James Altland, Oregon State University Extension nursery crops specialist. Mowing isn't real effective, as bindweed grows along the ground until it comes in contact with other plants or structures. It grows up and over anything in its path. Much like pole beans, bindweed's stems rotate in a circular pattern until they make contact with a solid structure (fence posts, other plants, etc.). Each stem wraps around the object as it grows. Be prepared to pull out or plow up all your field bindweed for two years if you want to avoid using herbicides, Altland advises. "To get rid of bindweed by plowing or pulling, it takes persistence and dedication as bindweed roots left in the soil after cultivation will regenerate its shoot system in about two weeks," said Altland, who works closely with Oregon's nursery industry out of OSU's North Willamette Research and Extension Center in Aurora. Pull it all up every three weeks, he said. "Repetitive cultivation throughout the growing season for at least two years should deplete the root system and provide control. Use the deepest cultivation implements available, such as a garden fork." Glyphosate containing herbicides (such as Roundup) are an option for the war against bindweed, as long as you can avoid having the herbicide spray or drift contact any other plants in your yard. These herbicides are absorbed by foliage and move throughout the plant to kill roots and shoots. Repeated applications of herbicide will be necessary to control bindweed, warned Altland. "Bindweed's root system can be so immense that insufficient herbicide is absorbed with a single application," he explained. "Use repeated applications, but allow the plant to grow and produce flowers before each subsequent application. The best time to control bindweed with glyphosate herbicides is when these plants are flowering. Identifying field bindweed can be a bit tricky. Its arrow shaped leaves grow opposite each other along each stem. When juvenile stems are broken, they exude a milky sap. The flowers are white to pink and trumpet-shaped and produce indeterminately throughout the year. For more information on how to identify field bindweed, including photos of both field bindweed and similar vine weed species such as hedge bindweed, visit Altland's OSU nursery crops weed control website. Potato Growers Should Check Fields For Pink Rot Infections By Marlene Fritz, University of Idaho Scientists at the University of Idaho College of Agricultural and Life Sciences are asking Idaho potato growers to scout their fields for pink rot in July and August and send suspect plants to them. At Aberdeen, UI Extension potato pathologist Jeff Miller and postdoctoral fellow Lyndon Porter are evaluating resistance to the fungicide mefenoxam in the pink rot fungus, Phytophthora erythroseptica. Tests they have conducted in the past three years indicate that more than 75 percent of this fungus' "isolates" from infected eastern Idaho tubers are already moderately resistant to mefenoxam, a chemical that's intended to control the disease. "Growers should start watching for premature wilting and roots with unusual brown to black lesions," says Miller. Top-priority spots to check are both waterlogged and water-stressed areas: high, dry ridges, saturated lowlands and rows beneath end guns. "Wilting could be a sign of another disease, like early dying, but don't assume that. We'd like to check and make sure." Pink rot infects tubers via fungus-infested soils. Although signs of wilt develop at the bases of stems, the worst damage occurs in the tubers themselves. When affected tubers are cut open, their "boiled textured" interiors turn pink, giving the disease its name. These discolored interiors are neither mushy nor slimy, but other diseases&emdash;including leak and bacterial soft rot&emdash;can quickly break down affected tubers in storage. Pink rot struck both eastern Idaho and Magic Valley potato fields in 2003, but growers held storage losses to a minimum by detecting the disease early, keeping most infected lots out of storage, and managing their storages carefully. "So far, our weather this year has not been favorable for pink rot," says Miller. Growers should send suspect potato plants to Miller (UI Aberdeen Research and Extension Center, P.O. Box 870, Aberdeen, ID 83210-0870) or bring them to their county Extension educator. For more information, contact Miller at (208) 397-4181. How To Make Your Garden A Safer Place For Pets By Carol Savonen, Oregon State University Many people who are avid gardeners are also avid pet owners. Pets and people enjoy being outside together, but gardening poses some hazards for your companion animals. Stacey Schatz, a veterinarian and an Oregon State University Master Gardener in Columbia County, wants those who garden and have pets to be more aware of hidden hazards to pet health and how to avoid them. Here are Shatz's recommendations to make the garden and its associated activities less hazardous to pets. Toxic Plants&emdash;Many common indoor and outdoor plants are considered toxic in some way. It is important to learn some of these plants, particularly if the pet is young, as puppies tend to be voracious chewers. However, for the average adult dog, the risks are generally minimal. Many toxic plants have to be eaten in large quantities to have significant effect. For example, rhododendrons are considered toxic, and the symptoms can vary widely. If a dog picks up a branch and chews on it, it may develop some mild, temporary stomach upset but should not suffer serious or long-term health problems. If a more herbivorous animal, such as a goat, chews and ingests the same rhododendron, it may have significant cardiac abnormalities. The difference is not in the species of animal but rather the eating habits. There are exceptions, of course, such as the castor bean plant, oleander and yew, where even a minute dose may be fatal. Remember that some plants we consider safe food items can be a problem for dogs. These include grapes, avocados, onions and garlic, and in some situations, potatoes. Many lists of toxic plants can be found in books and on the internet, and there is also a national poison control hotline for animals. Toxic Chemicals&emdash;A pet is at much greater risk from commercial chemical products than from plants. Rodent baits, slug bait, insecticides and herbicides need to be stored and used properly. Far more toxicities are seen from these products than from toxic plants. Physical Risks&emdash; Consider those plants that are stiff, sharp, prickly or sword-like, such as yucca or roses. Keep these plants to the back of the border, behind the low fencing or at least off the main thoroughfare. Power Equipment&emdash;Remember that lawn mowers, edgers, weeders and other power equipment have the potential to kick up rocks and other material. These items are likely to be launched at eye level. Confine the pet while using these types of equipment. To learn more, Schatz recommends visiting the website for the National Animal Poison Control Center. Male Blister Beetles Are Well-Named From University of Idaho's HomeWise Give a blister beetle a squeeze and, if it's the male of the species, you'll wish you hadn't. "They literally cause blisters when they're mishandled," says Ed Bechinski, University of Idaho Extension integrated pest management specialist. "If you pick up a male blister beetle in your bare hands, it can exude droplets of toxin-spiked blood from places where you imagine its knees to be. You end up with a blister that lasts about five days&emdash;possibly up to two weeks. It's not painful unless it breaks." In addition to pencil-eraser sized blisters on skin, male blister beetles can also cause internal blisters when animals like horses eat beetle-infested hay. The beetles may have been dead for months but the horse will still suffer the effects&emdash;sometimes fatally. Obviously, a protective mechanism like this can ward off a lot of predators. It even protects female blister beetles, who can't make the toxic chemical&emdash;called cantharidan&emdash;but who look like the males. During mating, the males also pass some cantharidan to the females, who store it internally and squeeze it next to their eggs as they lay them. That helps protect the eggs from ants and other predatory insects. Oddly, while many animals are vulnerable to the blistering effects of cantharidan, the ant-like flower beetle actually thrives on it. "The male will ride on the back of the blister beetle and eat the cantharidan it exudes," says Bechinski. Okay, enough strange-but-true garden tales. What should you do if you find the thin, half-inch-long beetles&emdash;black, gray or possibly striped&emdash;feeding on your flowers, vegetables or shrubs? Because their larvae eat the egg pods of grasshoppers, Bechinski advises leaving blister beetles alone unless they occur in "massive" numbers and do significant damage. "They tend to appear rather suddenly and disappear just as suddenly," he says. "You wait a couple of days and they're gone. But if there's a lot of leaf-feeding activity going on, use a standard commercial insecticide that's registered for the plant." Bechinski says blister-beetle damage tends to be sporadic because the insects also release a communicating chemical&emdash;or pheromone&emdash;that helps keep the gang together. "You hardly ever find one or two," he says. "If you find them at all, you'll find a lot and they'll eat the leaves down to the veins. But it's very, very spotty." If you do find just a few blister beetles on your veggies or flowers and aren't prone to tolerate them, put on a pair of gardening gloves, pick them off and drown them in a bucket of soapy water. Oregon's War On Weeds Gets Help From Weedmapper By Bob Rost, Oregon State University The spread of noxious, exotic (non-native) weeds in Oregon costs the state millions of dollars annually in lost economic productivity and resources spent on weed control programs. Researchers at Oregon State University hope to enlist the help of landowners and land managers throughout the state in the war on weeds via an online-based weed information exchange called Weedmapper. "The idea behind Weedmapper is to provide agency officials, land managers and Oregon landowners with quick and easy access to the latest information available on the location and extent of noxious weed infestations around the state," said Doug Johnson, a rangeland ecologist in the OSU Department of Rangeland Resources, and leader of the Weedmapper project. "In addition, Weedmapper is designed to help more people get involved in the weed control effort," Johnson added. "The site invites any Oregon landowner with Internet access to report sightings of exotic weeds." The recently completed website was developed at OSU by a team of range scientists and web information technologists, many of whom are OSU graduate students. The Rogue River National Forest, Oregon Department of Agriculture, U.S. Department of Agriculture and Bureau of Land Management cooperated with the OSU Rangeland Resources Department in the design and construction of Weedmapper. Weedy invaders such as Russian knapweed, scotch thistle, gorse and tansy ragwort cause harm by displacing native plants on forest and rangelands, damaging wildlife habitat and grazing areas for livestock. In addition, some weeds such as tansy are toxic to livestock. The more widespread invasive noxious weeds become, the greater the damage they cause. For example, tansy ragwort, which is poisonous to livestock, is estimated to have caused economic losses of $5 million annually in Oregon for many years until weed control strategies began to reverse the spread of tansy in the late 1990s. The noxious weed database within the Weedmapper web site includes photographs and descriptions of weeds as well as maps showing the extent of known infestations. The maps are viewable at the state, county, township or section (square mile) level. Weedmapper also includes risk assessment tools to help users understand the potential scale of noxious weed infestations in Oregon, and links to other sources of information on weed management and control. However, one of the most valuable components of the website may be the noxious weed sighting report feature. "The weed report form incorporated into the Weedmapper web site was developed by the Oregon Department of Agriculture weed control program," said Johnson. "Reports submitted via the website go directly to the ODA and are independently verified before the information is added to the statewide noxious weed database. The mapping feature of the website allows reporters to indicate the specific position of a noxious weed sighting in degrees of latitude and longitude. "Our hope is that the reporting tool in Weedmapper will generate citizen involvement in statewide control efforts," said Johnson. Tim Butler, manager of the Oregon Department of Agriculture's Noxious Weed Control Program, also hopes Weedmapper will make a difference in Oregon's war on weeds. Early detection is the key to controlling the spread of noxious weeds, Butler said. With the large numbers of people and products moving in and out of Oregon, it's difficult to keep noxious weeds out of the state, he added. "For many years we maintained a weed database based on annual weed sighting reports from state and federal land managers and county weed supervisors," said Butler. "With the introduction of Weedmapper, gathering and sharing information about noxious weed infestations can be done more quickly and effectively and more Oregonians can get involved in helping track noxious weeds."

Fortified Food Wrap Is Good Enough To Eat By Peg Herring, Oregon State University What do you get when you cross an egg white with a crabshell? You get a thin film that prevents food from spoiling and can be eaten along with the food that it wraps. No joke. It can even be fortified with vitamins and minerals so the food and the film together make a more nutritious fare. This super packaging is the latest technology from Oregon State University's Department of Food Science and Technology. The film combines two key ingredients: a fiber from shellfish (chitosan) and a protein from egg whites (lysozyme). Its discovery combines the ingenuity of two OSU researchers: Yanyun Zhao, a food technologist and specialist in value-added products, and Mark Daeschel, a microbiologist and specialist in food safety. Working with postdoctoral research associate Su-il Park, Zhao and Daeschel began experimenting with ways to combine lysozyme and chitosan to create an anti-microbial food wrap. The product they have developed looks like familiar sandwich wrap, but delivers much more. Because it is made entirely from food products, the wrap is edible. It's so thin that it doesn't interfere with the texture of the food it covers. And it is made from powerful natural antimicrobials, so it keeps fresh food from spoiling. A patent application has been filed for the technology, which has many potential applications. "You can use it as a film to wrap foods or you can use it as a spray or dip to coat foods," Zhao explained. "And you can enrich the film or coating with extra nutrients, such as vitamin E and calcium, to boost the nutritional value of the food." For several years, Zhao has been experimenting with chitosan to develop thin protective coatings for perishable fruits and berries. Chitosan is a key ingredient in crabshells and shrimp shells, the tough exoskeleton that serves as protective armor. She confirmed that the natural polymer in chitosan inhibits the growth of microbes that cause rot in fresh berries and other foods. At the same time, Daeschel has been experimenting with lysozyme as a natural preservative in beer and wine. Daeschel found that the egg white protein was just as effective as chemical sulfites in preventing unwanted microbial growth, without compromising the taste or quality of the product. The scientists realized that their two key ingredients each have particular antimicrobial properties that could enhance each other if combined. "These are naturally occurring ingredients," said Daeschel. "The chitosan is derived from seafood shells, much of which is otherwise wasted. This is a good example of adding value to an existing product." The next challenge for Zhao, Daeschel and Park will be to develop practical applications for their super food wrap. The possibilities extend to packaging for ready-to-eat meats such as hot dogs, sausage and luncheon meat; packing films for cheese slices, blocks and sticks; and coatings for sliced fruits and vegetables that are highly perishable. OSU Helps To Develop New Product: Fresh Fruit With Fizz By Carol Savonen, Oregon State University Imagine biting into a juicy apple or pear and experiencing a zinging, fizzy sensation. "Fizzy Fruit," a carbonated fruit should be commercialized soon, thanks in part to work done by Oregon State University researchers at the Oregon Food Innovation Center in Portland. Fizzy fruit was discovered by accident. Galen Kaufman, a Texas neurobiologist and Fizzy Fruit's inventor, discovered it while he was on a sailing trip. Biting into a pear that had been in a cooler chilled with dry ice, he sensed an unusual fizziness in the fruit. He found the carbonation delightful. Being a scientist, Kaufman quickly figured out that some of the dry ice in the cooler had sublimated, changing from a solid directly into carbon dioxide gas, entering the fruit. Kaufman's pear had become carbonated by the dry ice used to chill the sailboat cooler. Kaufman liked fizzy fruit so much that he decided to try to develop it into a commercial product. He applied for a U.S. patent for the intellectual concept of carbonated fruit. Then, he contacted OSU professor John Henry Wells, renowned expert in food packaging and storage at the Food Innovation Center in Portland. Kaufman wanted the center's help to develop a patentable process of carbonating fruit on a commercial scale. OSU's Qingyue Ling, the product development engineer for the Food Innovation Center, came up with designs for the manufacture of fizzy fruit, including computerized-controlled techniques. Patents were filed and are pending, with OSU and Kaufman's company "Fizzy Fruit, North America" as co-owners, according to the OSU Technology Transfer office. "Think about a soft drink with CO2," said Ling. "The soft drink has carbon dioxide gas dissolved in it. As the temperature is raised or the pressure is lowered, the gas is released as bubbles. The same thing happened to Kaufman's fruit." The inventor and the OSU researchers envision that the fizzy fruit may encourage people to eat healthier diets by consuming more fruit. Ling foresees fizzy fruit as becoming a big hit with school children. "Children like something fun, like fizzy fruit," said Ling. "And their mothers like the fact that their kids will be eating more fruit. "Eating more fruit will also help with the national obesity epidemic, "he added. Fizzy Fruit plans on marketing its new product to school lunch programs and other children's markets. This work is the first commercialization of a patent at the Food Innovation Center in Portland. This project is one of dozens at the center, jointly run by OSU and Oregon Department of Agriculture. The center develops food products and concepts for food producers, processors, marketers and entrepreneurs. The OSU and Oregon Department of Agriculture staffs at the center include technologists, engineers, economists and business experts. For more information, contact Qingyue Ling, Food Innovation Center, OSU, 1207 N.W. Naito Parkway, Suite 154, Portland, OR 97209, 503-872-6652. Mustard&emdash;Fights Pests, Makes Fuels From University of Idaho's Ag Knowledge Mustard, canola, and their close relatives pack a chemical punch Idaho's agricultural producers may learn to love thanks to the work of UI soil biochemist Matt Morra. Morra tracks how the chemicals responsible for mustard's pungent bite affect other plants and animals in a search for new weapons against weeds and pests. Meal leftover from pressing oil from the tiny seeds is packed with glucosinolates. Combined with natural enzymes and water, glucosinolates yield isothiocyanates that eliminate pests, then quickly break down to harmless compounds. The ultimate result may lower fuel prices. Morra and UI plant breeder Jack Brown hope making the meal more valuable as a pesticide will make the oil cheaper. They hope the cheaper oil could help jumpstart the biodiesel industry. For more information: Contact Morra at mmorra@uidaho.edu or www.info.ag.uidaho.edu/agknowledge OSU Extension Pub Takes Mystery Out Of Pressure Canning By Carol Savonen, Oregon State University Pressure canning is the only safe method for canning meat, poultry, fish and non-pickled vegetables except tomatoes. Using boiling water canners for these low-acid foods poses a real risk of botulism poisoning, warns Carolyn Raab, Oregon State University food and nutrition specialist. Botulism is caused by a toxin produced by bacteria called Clostridium botulinum. These bacteria are very hard to destroy at boiling water temperatures. But at the higher temperatures reached in a pressure canner, they are easier to kill. Pressure canners are available in different sizes. Small pressure cookers (6 or 8 quart) are no longer recommended for home canning. Processing will be inadequate due to faster heating up and cooling down times than in the larger canners. All low acid foods should be processed at temperatures of 240 to 250 degrees. Pressure canners reach theses temperatures when they are operated at 10 to 15 pounds of pressure per square inch as measured by the gauge. At temperatures of 240 to 250 degrees, the time needed to destroy bacteria in low-acid canned food ranges from 20 to 110 minutes. The exact time depends on the kind of food, the way it is packed into jars and the jar size. Pressure canners have either a dial or a weighted gauge. Dial gauges should be checked for accuracy each year. About two-thirds of OSU Extension county offices offer this service. Contact your local county Extension office for information. The OSU Extension Service offers a 15-page publication that takes the mystery out of using a pressure canner. "Using and Caring for Your Pressure Canner" outlines different types of pressure canners, what features to look for when you buy a new or used pressure canner and how to care for, use, store and test your pressure canner. To order "Using and Caring for Your Pressure Canner" (PNW 421), send your request and a check or money order ($1 per copy plus $3 for shipping and handling) made out to OSU to: Publications Orders, Extension and Experiment Station Communications, OSU, 422 Kerr Administration Bldg., Corvallis, OR 97331-2119. For answers to questions about pressure canning foods, contact the Food Safety/Preservation Hotline operated by the Oregon State University Extension Service from July 15 to Oct. 15 at 1-800-354-7319, Monday through Friday from 9 a.m. to 4 p.m. (except holidays). How To Reduce Risk Of Wildfire On Your Property By Carol Savonen, Oregon State University More and more people are living in rural or remote forested settings. And every year more and more of these homes are destroyed by wildfire, costing tens of millions of dollars in damages and suppression costs. Many of these homes could have been saved had landowners taken a few precautions to reduce fuels and make their home and property more "defensible." Will your home and property survive should a wildfire occur in your area? "Although you may have fire protection provided by a local fire protection district, don't live under the illusion that firefighters will be able to extinguish a wildfire before it gets to your home and property," warned Stephen Fitzgerald, forestry specialist with the Oregon State University Extension Service in central Oregon. "In the event of a large wildfire, firefighters will not enter property that has hazardous fuel conditions, placing themselves and fire-fighting equipment at risk. Even if you have fire protection, it is your responsibility to take action and reduce fuels and other hazards around your home and property, said Fitzgerald. To lessen the risk of wildfire, Fitzgerald offers a few simple steps to protect your home and property. A good time to do these activities is before the fire season, and many can be completed in just one weekend. • Create a "green-belt" (i.e., lawn) 10- to 30-feet wide around your home. • Landscape with fire-resistant plants in both irrigated and non-irrigated portions of your landscape. • Clean and remove pine needles and other debris from your roof and gutters annually. • Prune trees up to eight to 10 feet to eliminate "fuel ladders." You can vary the pruning height so your trees are more natural appearing. • Reduce the number of native shrubs under trees and in non-irrigated portions of your property. • Thin trees so that there is about 10 feet between tree crowns; clean up thinning debris. • Consider removing trees up against your house or with branches overhanging the roof. If you can't bring yourself to remove these trees, prune branches up so they are not in contact with the side of the house or roof. • Keep firewood stacked away and uphill from your home. • Replace a wood shake roof with a fire-resistant roof as soon as possible or feasible. • Display your address and lot number clearly at the end of your driveway. When building a new home in a forested area, it helps to use fire-resistant siding and non-combustible composition, tile, or metal roofing materials; limit the amount of deck area because hot embers can ignite wooden decks; build on a level portion of your property when possible (fire burns faster on slopes); install alternative water (i.e. cistern) sources for firefighters because electric power often fails or is shut off during a fire making your well and outside faucets unusable; and create adequate access to your property for fire-fighting equipment to enter and egress easily. Check with your local fire protection district for ingress/egress standards. For more information, Fitzgerald and OSU Extension horticulturist Amy Jo Waldo offer a publication on-line: Fire Resistant Plants for Home Landscapes. Printed copies are also available by sending a request for "Fire Resistant Plants for Home Landscapes" and self addressed stamped envelope and 60 cents a copy to: Deschutes County Extension, 1421 S. Hwy. 97, Redmond, OR, 97756-9654. To learn more online about defensible space and landscaping for fire protection, visit: • Firewise Home Page • Oregon Dept. of Forestry Home Page • Colorado State Forestry Service • U.S. Forest Service Fire HomePage Contact your rural fire protection district office for fire-related information and regulations. Local field offices of the Oregon Department of Forestry and the OSU Extension Service can also help provide additional information or help direct you to other sources of information. Weed Management Considerations For Chemical Fallow By Fabian Menalled Montana State University Extension Service Cropland Weed Specialist In the driest parts of the Northern Great Plains, moisture is usually the most limiting factor to crop production. In these areas, the combination of direct seeding and chemical fallow represents a viable option to conserve scarce moisture. It also protects the soil from water and wind erosion and eliminates the expenses of tillage operations. Without tillage, growers necessarily rely on herbicides to manage weeds. However, the success of a fallow period goes beyond multiple herbicide applications and encompasses different aspects of the cropping systems. An effective chemical fallow starts several months before harvest. Indeed, the most efficient tool to suppress weeds is a well established and competitive crop. Weeds that emerge during the spring and summer may be too large to be managed during the fallow period. As a crop matures, it becomes less competitive as it intercepts less sunlight and uses less moisture and nutrients. Weeds allowed to grow during this period may have no significant impact on crop yield, but could take a toll on moisture and nutrients. Moreover, through seed production, these weeds may increase dockage and replenish the seed-bank compromising future crops. Thus, proper weed management during the crop phase is essential for successful chemical fallow systems. At harvest, it is very important to properly distribute crop residue across the field. If crop residues are allowed to accumulate in windrows behind the combine, inadequate weed control may occur during fallow due to uneven herbicide interception. Also, the cooler and wetter conditions of windrows may favor weed germination. These problems can be avoided by checking the residue distribution pattern of the combine. If crop residue distribution is uneven, consider using a residue spreading attachment such as a straw and chaff spreader. The early post-harvest period also presents its own weed management challenges. Weeds are usually easier to control when they are small. Thus, if rain allows germination of weeds and volunteer crop during the early post-harvest period, a timely application of Roundup (glyphosate), Aim (carfentrazone), Express (tribenuron) or 2,4-D will control this vegetation before it becomes too large. Also, the use of Roundup in conjunction with a residual herbicide such as Spartan (sulfentrazone) can enhance control of large individuals while providing extended weed control. A weed-free fallow period is essential to maximize moisture storage and nutrient retention. However, weed management during fallow presents several difficulties. First, weeds that have escaped control during the early-fallow period are usually too large or metabolically stressed due to hot weather and water limitation to be controlled with herbicides. Second, herbicides used during the summer fallow period compromise the crops that could be planted during the next growing season. To avoid crop injury due to herbicide carryover, it is essential to pay special attention the herbicide degradation rates and the rotational restrictions. Third, cold temperatures may compromise the effectiveness of herbicides. Finally, late germinating weeds such as kochia, Russian thistle, and prickly lettuce may become a nuisance during this period. Periodic scouting of the fields and timely herbicide application may help minimize the impact of these late weeds. There are many herbicides that can be used in a chemical fallow system. Among them, Aim, a non residual product to control actively growing broadleaves including ALS resistant kochia; Curtail (clopyralid + 2,4-D), a broad spectrum herbicide to manage broadleaf weeds including Canada thistle, wild buckwheat and common cocklebur; Gramoxone Extra (paraquat) to control emerged annual grass and broadleaf weeds of less than six inches height; Roundup for annual and perennial grass and broadleaf control; and Spartan to control several small seeded broadleaves including kochia and Russian thistle. A complete list of the herbicides available and their application rates can be found at the Weed Management Handbook published by the Montana, Utah and Wyoming Cooperative Extension Services. As always, precautions should be taken to maximize the effectiveness of herbicides. For example, Roundup is one of the favored products for chemical fallow. However, it does not control all weeds equally and it should be applied when plants are less than 12 inches tall. When dealing with larger and harder to manage weeds such as kochia, wild buckwheat and Canada thistle Widematch (fluroxypyr and clopyralid) and Spartan are favored. Because herbicides are at the core of direct seeding and chemical fallow systems, it is very important to minimize the risk of selecting herbicide resistant biotypes. If the same herbicide is repeatedly used for several years, the applicator removes all susceptible weeds favoring the establishment of resistant plants. For example, Ally (metsulfuron) and Harmony GT (thifensulfuron) provide good control of numerous annual broadleaf species. However, these two herbicides are both sulfonylureas, killing weeds by targeting the same enzyme. Continuous use of Ally and Harmony GT increases the chances of selecting for sulfonylurea resistant biotypes. Proper rotation of herbicides with different site of actions, crop rotation and rotation of management strategies remains the best option to prevent the appearance of herbicide-resistant weeds. In summary, in the driest parts of the Northern Great Plains there is little tolerance to moisture and nutrient depletion by weeds. In these areas, a season-long chemical fallow is a viable option as it helps growers replenish soil moisture and reduce soil erosion. Because tillage is eliminated from the production system, herbicides remain a main option to control weeds. However, weed management in chemical fallow systems goes beyond multiple herbicide applications and includes all phases of the cropping system. A successful weed management program in a chemical fallow system can only be achieved through the establishment of competitive crops, proper crop residue management and timely herbicide applications. Because of the heavy reliance on herbicides, herbicide rotational restrictions and prevention of herbicide resistance are essential. 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. UI Scientist Nets New Herbicide For Spuds From University of Idaho's Ag Knowledge When UI weed scientist Pamela Hutchinson read about a new herbicide for soybeans four years ago, she resolved to see it labeled for use in Idaho potatoes. Offering a novel mode-ofaction entirely different from other potato weedkillers, Spartan looked promising against hairy nightshade and herbicide-resistant kochia, common lambsquarters, and redroot pigweed. Hutchinson, based in Aberdeen, persuaded manufacturer FMC to support the necessary research to register Spartan in potatoes&emdash;a crop considered "minoracreage" by national standards. The result of her team's efforts: a newly registered weedkiller for Idaho growers that destroys even herbicide-resistant broadleaf weed seedlings as they emerge in potato fields. "We had to lobby aggressively," says Hutchinson, "but growers need more choices in herbicides in order to prevent or delay development of herbicide-resistant weeds." Contact her at phutch@uidaho.edu.

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