Wallingford Weed

 Noxious weeds are non-native plants that, once established, are highly destructive, competitive and difficult to control. They have economic and ecological impacts and are very difficult to manage once they get established. Some are toxic or a public health threat to humans and animals, others destroy native and beneficial plant communities.

–King County Noxious Weed Control Program

I frequently try to persuade people not to kill things just because they are inconvenient (animals, insects, you may remember my moss post). I was going to write about moles, but it’s actually a perfect moment to bring spurge laurel (Daphne laureola) to your attention, because it’s a noxious weed in bloom NOW. This plant is poisonous and persistent. It deceptively grows in plain site, masquerading as an anonymous broadleaf evergreen shrub.

Here’s what the flowers look like (they’re small and clustered on the stem tips)

Not all weeds are “noxious” some are just irritating or disturbing.  The noxious designation is a legal term reserved for the Really Bad ecosystem destroyers. You can read more about other noxious weeds in this pdf.

If you have Daphne laureola on your property, King County does not require you to get rid of it, but, like blackberries and ivy, it is recommended that you do so.

And it is important to control it. Not only will it spread locally, seeds and plants get moved around – on our shoes, tires, in soil. When we travel to a place like the San Juan Islands, where this plant is a threat to sensitive Madrone ecosystems (and control IS required), there is a good chance it will hitchhike along.

My personal opinion is that, like English holly, ivy, and old man’s beard, it will grow unnoticed within our greenbelts for years before people realize what a problem it has become (see aforementioned pdf). As the climate warms, many invasive plants are expected to do better, and this one almost certainly will.

It can live in deep, deep shade, no problem – also in sunnier areas; drought is not a problem for it. It has a long, stout, tap root that will resprout if not completely removed (which is darn hard because it grows surprisingly deep early on). Birds eat the NUMEROUS seeds, and drop them next to big trees. By the time you notice the plant, it is just about impossible to extricate it from the tree roots.

What can you do?

• Dig it up. If you see this plant in your parking strip, skulking in your alley, or your neighbor’s yard, put on some protective gear (rubber gloves, long sleeves, long pants, shoes and socks) to guard against the rash-producing sap (not a big problem if you’re careful – the cut stems will exude a latex-y substance)
• Dig some more If you can’t get ALL of the root, then check back later to see if it has sprouted more leaves, and keep cutting the top to starve the roots
• Bag the top if it has seeds (also poisonous) to make sure they don’t get scattered around
• If you see it in a park, contact the Parks Department [email protected] and politely suggest it be removed, noting its place as a Class C noxious weed in King County
• Once you meet and destroy it, you will be able to educate your friends and neighbors to watch for it too. Then we can all work on it together.

If you’re not sure…

Identification is easiest NOW while Daphne laureola is in bloom. Later, there will be oval, green fruits, ripening to black.
The leaves are very similar to another plant called spurge (Euphorbia), so it’s not as easy to tell the difference when it’s not blooming, but you can cut a sample and take it to a nursery for i.d. or e-mail me and I’ll take a look. It also smells really awful, so that’s a clue.

More noxious weeds FAQ at http://www.kingcounty.gov/environment/animalsAndPlants/noxious-weeds/faq.aspx