Warning: Don't pick the roadside blackberries
In April 2019, we (Non Toxic Southern Oregon) received one year of Jackson County Roads Department pesticide spray records. After digitizing the handwritten records, we discovered the Roads Department sprayed 2,575 gallons of concentrated products of 18 different pesticides, diluted into spray tanks, over that one year.
We estimated 2,585 acres in roadside areas were sprayed; we estimate this is sufficient to kill all vegetation on nearly 2,000 football fields.
Over 60% of the total volume used contained the chemicals glyphosate and Diuron, both designated as highly hazardous by the Pesticide Action Network International, a coalition of 600 experts in nearly 90 countries.
So, think twice before you stop to pick those wonderful blackberries along our roadsides — they may be contaminated with pesticides.
Overlaying the county’s pesticide spray record data with the data from the Middle Rogue Pesticide Stewardship Partnership 2015-2017 Biennial Summary (MRPSP), we identified locations where pesticide applications were sometimes made in the vicinity of streams or creeks that contained measurable levels of roadside pesticides.
We noted several of the same pesticides used along roadsides were identified in local streams. Diuron, Sulfometuron, and Imazapyr were found in 47%, 23%, and 11% of the local streams sampled.
Historically, the occurrence of pesticides in local creeks and streams within the Rogue Valley has been attributed to agricultural and forestry practices. However, some of these pesticides, such as Diuron, are designed to maintain bare ground in a roadside gravel shoulder. Linking the type of pesticides found in these streams and their designed use, the evidence leads us to conclude that roadside pesticide spraying is another likely contributor to the dispersal of pesticides.
The partnership’s stream surveys detected the herbicide Diuron in 71 of 151 samples, exceeding the EPA benchmark environmental concentration limits one-third of the time. Diuron is highly toxic to beneficial aquatic invertebrates that use our streams for some or all of their life cycle. Aquatic invertebrates such as dragonflies, stoneflies, mayflies and midges as well as mussels, crayfish, snails and other aquatic organisms, are vital links in the aquatic food chain, providing nutrients to larger organisms such as fish, frogs, salamanders, reptiles, birds and mammals.
Additionally, both Diuron and 2,4-D are known endocrine (hormone) disruptors. Endocrine disruptors are chemicals that interfere with the body’s hormones and produce adverse developmental, reproductive and neurological illnesses, cancers, and immune disorders in both humans and wildlife. These two herbicides are potent endocrine disruptors in minute concentrations, as low as parts per billion or 1,000-fold below the concentrations of pesticides when they are sprayed.
Glyphosate is the most common herbicide used by Jackson County Roads. Exposure to glyphosate is also now widely accepted as a cause of blood cancers in humans, shortened pregnancy lengths, possible endocrine disruption activities, birth defects, liver disease in experimental animals, and breaks in DNA in laboratory studies that could lead to cancers.
Do weed killers harm insects and animals? Yes.
Why is this important? In aquatic environments and stream sediments, pesticides persist for weeks, months and sometimes longer. Following rain and runoff events, pesticides are capable of moving and exposing many new habitats and beneficial life forms far from their original points of application. Evidence of the occurrence of this flush and transport is confirmed by the Pesticide Stewardship Monitoring data.
Scientists at the University of Texas recently showed that glyphosate removed important beneficial bacteria from the gut of honeybees because glyphosate also acts as an antibiotic, and the bees subsequently became more susceptible to diseases.
This year, scientists sounded the alarm over the precipitous decline in insects worldwide due in part to urbanization and the widespread proliferation in the use of pesticides. Scientists in Portland have called the insect decline catastrophic, and declared that a “serious reduction in pesticide usage” is key to preventing the extinction of up to 41 percent of the world’s insects, including pollinators, within the next few decades.
Numerous municipalities throughout the world have already taken action to control the use of pesticides in public areas. Roadside management strategies and methods that don’t rely on toxic pesticides are already in use in Oregon. Strategies include non-toxic, organic pesticide applications during low insect activity and mechanical methods such as mowing, steam applicators and planting of native vegetation. Why not here?
Add your name to our growing list of supporters! We will present our report to the commissioners at 9:30 a.m. Wednesday, Nov. 6, at 10 S. Oakdale, Medford.
Ray Seidler and Kristina Lefever live in Ashland. Alisa Sawich lives in Medford. All are members of Non Toxic Southern Oregon.