Our creeks and waterways are in trouble these days, from all the legacy pesticides showing up in sediment and water samples, long after they were sprayed, from miles away. These pesticides remain toxic to some of the water critters today, as they were to pests on the landscapes, when sprayed years ago.
Most likely, the pesticide residue found in California waterways did NOT come from agricultural practices, however, but rather from urban gardeners. Most growers depend on Pest Control Advisors (PCA’s) who are professionally trained to spray pesticides.
Growers are also required to report to the County Ag Commissioner all potentially toxic products used in their operation. Finally, growers are also required to monitor their local streams’ and rivers’ water quality for pesticides residue as part of their discharge permit from the State.
Urban home gardeners, on the other hand, have no government oversight when it comes to pesticides used at home, yet local municipal governments are required to meet stormwater permit requirements for their community’s urban runoff. It’s a very challenging situation for local municipalities to be held responsible for a problem that is not directly in their hands, but rather is in the general public’s hands.
In August 2021, local cities are required to file a Pesticides Management Plan with their regional water board. Cities will then be expected periodically to monitor their rivers and creeks for pesticides, specifically pyrethroids. The management plan must address how their outreach program will educate and encourage the public to reduce its use of pesticides. Hopefully, local water quality will improve over time through these strategies. Enter UCCE Master Gardener programs with their great online resources, especially the Integrated Pest Management (IPM) website! http://ipm.ucanr.edu/index.html
As an example of solving a common garden problem, let’s look at a pest which may be gnawing through your garden’s tender transplants, and highlight a few ways to eliminate the problem without first spraying something which will end up killing critters downstream.
European earwig, Forficula auricularia- Accidentally introduced into North America in the early 1900’s, they seem here to stay. Feeding at night, these nocturnal pests can do a lot of damage to your irrigation lines, leaky roof downspouts, or hose bibs. Females look for these places to breed. When you spot them, return with a trap.
IPM measures first
Set your traps at night, or just after dusk. Using rolled up newspaper or corrugated cardboard, lay these rolls near where you suspect earwigs. In the morning, take your “rolled trap” and empty in a bucket of soapy water. Continue trapping until no earwigs are caught. Another more involved trap design uses tuna or cat food cans, with ½ inch oil and a bit of bacon fat or tuna oil, set in a hole at ground…