Planting Edmonds is a monthly column written by members of Edmonds Floretum Garden Club.
Garden weeds are my bugaboo. Let’s dive in, Edmonds, because you have more of these than I’d like to see.
What is a weed? Experts have written many words in attempts to answer that question. Some will say it is simply a plant in the wrong place. I particularly like this from Oregon State:
“A weed is …
- A plant out of place.
- A plant that interferes with human activities.
- A plant whose negative characteristics outweigh its positive characteristics.
- A plant whose positive characteristics have not yet been discovered.”
Gardeners/readers are already nodding, thinking about all the things that fit that last descriptor.
The Washington State Noxious Weed Control Board says, “the term ‘noxious weeds’ includes non-native, invasive:
- Flowering plants
- Shrubs and trees
- Aquatic plants
About half of all invasive, noxious weeds are escapees from gardens; the rest are plants accidentally introduced to Washington through human travel and trade.”
Pictured below are a couple of those fugitives, yellow archangel and vinca, on the run through a Woodway ravine.
We’ll set aside aquatic plants for the purposes of this missive. It’s almost too much to think about what lies in the murky depths, out of sight, free to multiply undisturbed.
The Noxious Weed Board tracked and evaluated many weeds for a long time before including them in the list. They categorize these weeds into classes:
“Class A noxious weeds are non-native species whose distribution in Washington State is still limited.
- Eradicating existing infestations and preventing new infestations are the highest priority.
- Eradication of all Class A plants is required by law.
Class B noxious weeds are designated for mandatory control in regions where they are not yet widespread. Prevention of new infestations in these areas is the primary goal.
Class C noxious weeds are either already widespread in Washington or are of special interest to the agricultural industry.
- The Class C status allows a county to enforce control if it is beneficial to that county (for example: to protect crops).
- Other counties may choose to provide education or technical support for the removal or control of these weeds.”
Have you come across common crupina, dyer’s woad or kudzu? No? That’s perfect, because these Class A weeds are not widespread in Washington and are immediate targets for eradication when a report is received.
Two Class A weeds you may want to keep an eye out for in Edmonds are garlic mustard, which has been reported nearby in Shoreline, and giant hogweed, which I have witnessed growing in the Edmonds Bowl. Avoid contact with its thin sap at all costs, as it can cause painful blistering and persistent photosensitivity. Any Class A weed you see should be reported to the county and must be eradicated by the property owner. Report important weed sightings to your county coordinator (contact info below), or via an app for your phones,
Have you noticed any of our four types of knotweed (all Class B) lurking in your shrubs? Not one to be trifled with, knotweed is so harmful to the larger environment that England has knotweed-sniffing dogs trained to find the underground rhizomes before they emerge, becoming dense thickets that choke out all surrounding vegetation, leading to creek bank destabilization and loss of native habitat. We are required to control it, but you should get expert advice before attempting it.
Have you read about the introduction of Himalayan blackberries (Class C) to Washington state? We have horticulturist Luther Burbank to thank for that. He was attempting to develop a thornless berry but instead marketed all over Western Washington the wickedly sharp beast we know today, and then Mercer Island named a park after him! Feel free to eat as many blackberries as you can find later this summer and call yourself a weed warrior.
If you have blackberries growing on your land, my sympathies, but you can win against this foe. Each mature plant has a softball-sized “brain,” a thick root just below the soil surface. Hack your way toward it and you might be pleasantly surprised how it pops out of the ground with some hearty shovel action. If you don’t have time for that, cut the canes to the ground just after they flower. The plant will have spent its energy creating the next generation of blackberry plants and will be severely weakened by losing its top growth. This method lets you go back in the house and think about getting after it next year.
And what about English ivy (Class C), you ask? Like blackberry, it is too far gone for the state or county to do much but offer advice. You, dear homeowner, can protect your trees by cutting ivy at the base, letting the foliage on the bark die back, and then grubbing out the vines whenever you have the time and energy. It can be done with persistence. The photo below shows one way of keeping it in check, I guess.
The best strategy for weed control is this: “Don’t let that weed see Sunday.” I don’t know to whom I should attribute that bit of sage advice, but it is my mantra and it should be yours, too. Spend time in the garden, learn your plants, look for the sneaky invaders that are absolute champs at blending in and hiding out until they can send out rhizomes (hedge bindweed, a “Weed of Concern” in Washington and tricky to completely remove by hand) and/or shoot their seeds (the aptly-named shotweed, not on any list and thankfully easy to pull late-winter into spring) across the garden, and save yourself exponentially more work later by eliminating this season’s crop now.
Are you seeing the yellow flowers of creeping buttercup right now? That’s one to get after ASAP, particularly if you see it in or near your lawn. It’s tenacious but with a good digging tool you can pop out the leafy rosettes and halt its spread. The soil is moist and there’s no time like the present.
Got all of the above and more? Don’t know where to start? Consider the Bradley Method. While the Bradley sisters were restoring wild areas, the philosophy applies to cultivated landscapes and is essentially this:
1. Prevent Deterioration of Good Areas. Start by getting rid of weeds that occur singly or in groups of four or five.
2. Improve the Next Best. Choose a place that you can visit easily and often.
3. Hold the Advantage Gained. Resist the temptation to push deeper into the weeds before the regenerating natives have stabilized each cleared area.
4. Cautiously Move into the Really Bad Areas.
That’s really it. Take your morning coffee to the garden. Look around. Plan your attack. Do the same and a bit more the next day. It sounds a little like war, doesn’t it?
Because we are fortunate to live on the shores of Puget Sound, I strongly encourage you all to think of the salmon when making choices on how to proceed with weed control in the garden. Many creeks criss-cross our neighborhoods. All of them drain to the Sound. Salmon-safe practices help protect the fish and the Southern Resident Killer Whales which depend on them, and myriad other sea and land creatures residing just blocks away from our homes.
Simply put, if you can hand weed, do it. For truly intractable problems like a large stand of knotweed, choose commercial herbicides carefully, always selecting the least harmful option. Much has been written about Integrated Pest Management, which applies to weeds as well as insects and diseases. I’ll leave it to you to do your own research.
Are you exhausted yet? I am. If you didn’t get that shotweed before it exploded, if you have chosen to embrace the blackberries for another year of tasty pie and preserves, if you don’t have time for any of what I’ve written, there’s (maybe?) usually something good to say about weeds. I’ll leave you with this little bit of redemption from Penn State:
“Benefits of Weeds
Despite the negative impacts of weeds, some plants usually thought of as weeds may actually provide some benefits. Some attributes include:
- soil stabilization;
- habitat and feed for wildlife,
- nectar for bees;
- aesthetic qualities;
- add organic matter;
- provide genetic reservoir;
- human consumption; and
- provide employment opportunities.”
Snohomish County has its own weed program. Contact Snohomish County Weed Coordinator Geraldine Saw at Geraldine.Saw@snoco.org with all your questions. Click the handy links to learn more about identifying common weeds and find which weeds are designated for control:
Best wishes for a weed-minimized summer of gardening.
Bonus quiz below. How many weeds are pictured?
— By Tia Scarce
Tia Scarce has lived in Washington since 2002 and Edmonds since 2014, having first tested the waters in Sammamish and Kirkland. After graduating from the Lake Washington Institute of Technology with a degree in Environmental Horticulture, she completed the WSU Extension Watershed Steward program and volunteered with the Green Kirkland Partnership as a park steward where she ran ivy-removal work parties for middle school students and other community members. Tia is a past president of the Edmonds Floretum Garden Club.