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Salmon and Pesticides

Salmon are one of the most popular wild creatures in the Pacific Northwest, but their numbers are lower than they were decades ago.  

There are many reasons for this: excessive fishing in years past, land practices that reduced the quality of salmon habitat, land practices that put pollutants harmful to salmon into streams, and more. Many groups have carried out much salmon habitat restoration, improvements to animal manure management, salmon watching each fall, and some salmon research to help restore the salmon.

But there is still more that we all can do to help the salmon recover. Here are some key reasons why we should. Where salmon numbers are higher recreational and commercial fishing for them is usually greater. That brings in money and jobs. Scientists have determined that spawned out salmon contribute to the growth of over 100 species of plants and animals in the forest, supporting more healthy life in our Vashon forests and parks. Watching salmon return upstream with wiggles and splashes is very exciting for most people who are lucky enough to be there for those magical connecting moments. We owe it to future generations to provide that opportunity for them also.   

Research by the United States Geological Survey, the Washington State Department of Ecology, and King County, has found levels of 2,4-D harmful to salmon in some Puget Sound streams. The National Oceanic and Atmospheric Administration Fisheries (NOAA), found that pesticide products containing 2,4-D are likely to jeopardize the continued existence of all salmon species where it is used.

2,4-D kills broadleaf plants, and is found in many weed control and Weed and Feed products. I strongly encourage people not to use any of these 2,4-D containing products – especially near streams or near the shoreline. If you are unsure if a product contains 2,4-D, read the label to see if 2,4-D is an active ingredient. You can also find information on products that contain 2,4-D by going to the Grow Smart, Grow Safe website:

Here are a few salmon friendly ways to control weeds. 

Lay down a double layer of black plastic over gravel driveways in spring or summer to smother weeds. Roll up and re-use as needed.

Many people pour boiling water on weeds in sidewalk cracks, especially on hot sunny days.

There are a few products for sale that are referred to as pre-emergent weed controls and should be laid down in areas where you expect weeds - before the weeds come up. Concern Weed Prevention Plus and Preen Organic Vegetable Garden Weed Preventer are two of these salmon friendly products. Their active ingredient is corn gluten meal. There is another Preen with similar packaging that has trifluralin as the main active ingredient. Don’t buy it. Trifluralin was shown to be harmful to salmon in Puget Sound streams in studies carried out by NOAA Fisheries. 

Some people use flame weeders for patios, paths, and for emerging weeds prior to planting veggies and other plants. Be sure to follow directions carefully and don’t use when fire danger is high.

 Goats and sheep can be hired to eat blackberries, ivy, holly, and more.

Smart watering can also help control weeds. Drip irrigation targets most of the water at the roots of the plants you want to grow instead of broadcasting water all over, watering the weeds too.

Many people find manual weeding to be relaxing. There are many great hand weeding tools. Ask a salesperson to show you their latest and most effective tools. If you are not the type to be relaxed by weeding, consider hiring someone to weed for you, rather than use chemicals.

After you remove weeds, remember to mulch or plant desirable plants in that space. Otherwise there is a good chance the weeds will come back.

Vinegar sprays are another control option for weed seedlings and new growth, but be sure to wear eye protection.

If we all take steps to garden in a more green way we can help ensure that salmon will keep coming up our streams every fall.

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