Drift, droplets and ‘doughnuts’


News staff writer

February 28, 2007

A one-season trial on reducing spray drift of pesticides in orchards will continue this summer at the Mid-Columbia Agricultural Research & Extension Center.

Researcher Kelly Wallis said even with just last summer’s research, the OSU Extension Service center has some recommendations for growers that are effective and cheap.

“The questions we tried to address were how to affect the drift, how well did coverage work and what were the vegetative barrier types that worked,” she said.

She presented the findings of her and entomologist Helmut Riedl’s work at the Feb. 20 Winter Horticulture meeting. A separate study on the types of sprayers was presented by Paul Jepson, director of OSU’s Integrated Plant Protection Center.

Wallis’ team used sites near Mill Creek and Three Mile Creek in the vicinity of The Dalles. She said the intent was to keep the experiments simple and use what already existed. She said that the team wanted to look at what type of vegetative barriers would work best to keep spray out of salmon-bearing streams. They also wanted to see how using different types of sprayers could be more effective for growers.

Their study involved luminescent tracer dye that the team sprayed and 15-foot-tall poles erected to “catch” the spray. Wallis said because the dye faded quickly, the team had to spray and then run hard to collect the samples.

The team found that further study is needed to discover what types, how tall and what thickness of vegetative barriers work best to block spray drift. Jepson followed Wallis’ talk at the Pine Grove session and gave information on a summary of the different types of sprayers used in the research. Jepson and Nagajeran Ramalingam worked on the equipment portion of last summer’s trial.

“Drift happens,” Jepson said. “To help in avoiding drift, use weather forecasts to see when the best days are to spray.”

Jepson recommended growers use the Northwest Weather Service graphical forecasts. He advised that their maps of wind speed and direction were well-suited to the needs of Mid-Columbia farmers.

“The best conditions are a neutral, mild breeze to carry spray down into the foliage,” Jepson said. “This is a windy area; I sympathize with you.”

Conclusions for the different types of equipment showed that airblast sprayers had better coverage but higher drift. The team found that a plywood “doughnut” attached to an airblast sprayer was cheap and effective at reducing drift.

The team discovered that a plywood doughnut that covered half the area of air intake worked best for dormant season, while covering two-thirds of the air intake worked the best for the early to mid-season.

She also advised that when growers go to replace equipment that they consider tower sprayers and putting air induction nozzles on an airblast sprayer. Jepson said this change creates a bubblier droplet, which makes the spray drop sooner.

“There is a trade-off with the right-sized droplets at the right place at the right time,” he said.

The team also used Electrostatic, Hardi Tower, Proptec, Accutec, and Cropland sprayers in the studies.

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Parkdale third graders sing "12 Disaster Days of Christmas"

Welcome to your sing-able Christmas gift list. What follows is an emergency rendition of “12 Days of Christmas” – for outfitting your home or car in case of snow storm, earthquake, flood or other emergency. Read it as a simple list, or sing it to the tune of “12 Days” – you know, as in “ … and a partridge in a pear tree…” Not to make light of it, but the song is a familiar framework for a set of gift ideas that you could consider gathering together, even if the recipient already owns items such as a bunch of coats, tire chains and flashlights. Stores throughout the Gorge are stocked up on all these items. Buying all 12 days might be prohibitive, but here are three ideas for checking any of the dozen off your list (notations follow, 1-12.) The gift items needed to stay warm, dry and safe are also coded to suggest items in your abode (A) in your car (C) or both (B). 12 Gallons of Water (A) 11 Family meals (B) 10 Cans of propane (A) 9 Hygiene bags (B) 8 Packs of batteries (A) 7 Spare coats (B) 6 Bright red flares (C) 5 Cozy blankets (B) 4 Tire chains (C) 3 Flashlights (B) 2 cell phone chargers (B) 1 And a crush-proof first aid kit (B) Price ranges? Here’s a few quotes for days Three, Two, Four and Nine: n A family gift of flashlights (three will run $15-30, Hood River Supply, Tum-A-Lum) n Cell phone chargers (two will run $30-60) n Tire chains (basic set, $30, Les Schwab, returnable if unused for the winter) n Family meals ($100 or so should cover the basics for three or four reasonably well-fed days) n The home kit should be kept in a handy place near an exit, and remember that water needs to be replenished every few months. If you have a solid first aid kit already, switch out the gift idea with “and-a-sto-o-u-t- tub-for it-all …” Otherwise, it’s a case of assembling your home or car kits and making sure all members of the family know what the resources are and how to use them (ie flares and propane). Emergency situations are at worst life-threatening, at best deeply uncomfortable if you and your family are left without power for an extended period, or traveling and find yourself in a situation where you need to wait out a storm, lengthy traffic delay, or other crisis. Notes on the 12 gift ideas: 12 – Gallons of water: that’s one per person in a four-member family to last for three days, the recommended minimum to be prepared for utility outages. 11 – Easy-open packaged goods, energy bars, dried food and nuts are good things to include for nutrition. Think of what your family of four needs for three days to stay fortified and hydrated (see number 12). Can-opener also recommended 10 – If you have a propane camping stove, keep extra fuel handy. 9 – Hygiene bags: put packaged moistened towelettes, toilet paper, and plastic ties in large garbage bags (for personal sanitation) Resource list courtesy of Hood River County Emergency Management, Barbara Ayers, manager/ 541-386-1213. The county also reminds residents to Get a Kit, Make A Plan to connect your family if separated, and Stay Informed. See www.co.hood-river.or.us to opt-in for citizen alerts. Enlarge

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