State gets tough on invasive plants

If you have English ivy, butterfly bush or Scotch broom on your property (or have a hankering to have them), you need to know about their status in our state.

The Oregon Department of Agriculture's noxious weed quarantine (OAR 603-52-1200), which was amended earlier this year, contains changes in the ranking of these three popular, but potentially invasive, plants.

The English ivy quarantine perhaps draws the most attention. Effective June 1, 2010, the propagation, transport, purchase or sale of English ivy (Hedera helix) will be prohibited in Oregon. The prohibition includes outdoor, indoor, topiary or patio uses, as well as in floral arrangements. Go back and read those two sentences again. This can have quite an impact if you love English ivy — or even if you don't and want to rid your property of it.

The Department of Agriculture is serious about this, because English Ivy spreads easily and can literally smother trees and other vegetation if left unchecked. If you have English ivy on your property, this does not mean that the "Ivy Police" will arrest you, but it does mean that you may not carry the English ivy you pull down from your trees — or even that floral arrangement with ivy in it that you got as a gift — out to the forest and dump it. Cities, park departments and the state of Oregon spend thousands of dollars a year trying to eliminate this "pretty" plant.

Also effective immediately, the propagation, transport, purchase or sale of butterfly bush (Buddleja davidii) is prohibited. Sterile varieties are the exception here, as they produce little or no seed. These may be propagated and labeled as "Seedless Butterfly Bush," provided they produce less than two percent viable seed.

The problem with butterfly bush is that it can outcompete natural vegetation, making it a threat to the state's natural habitat. It can choke streams and is easily spread by birds, which love the seed.

The state's Noxious Weed Quarantine amendment also includes Scotch broom (Cytissus scoparious), regardless of variety or cultivar.

Like the earlier examples, the growing or selling of this plant is prohibited. Scotch broom burns fast and hot and is a serious threat when it comes to the spread of wildfires.

What should you do if you already have one of the seed-producing varieties of butterfly bush in your yard? If you can't bear to remove it, be sure to cut off all the spent blooms before they have a chance to form seeds.

English ivy goes in the garbage, not the recycle bin.

As for Scotch broom — the only plant whose blossom makes me sneeze — consider eliminating it, too, especially if you live on a property where wildfires may be a threat.

If you have further questions, telephone Gary McAninch at 503-986-4644 or e-mail him at

Coming up: On Monday, June 7, Steve Renquist, Douglas County horticulture agent, will teach a class on pruning shrubs, flowering trees and shade trees at the Oregon State University Research and Extension Center, 569 Hanley Road, Central Point, from 7 to 9 p.m. Cost of the class is $5. On Tuesday, June 15, master gardener Ellen Scannell will talk about how to grow and use herbs. The class will be at the OSU extension center from 7 to 9 p.m. Cost is $5. Telephone 541-776-7371 for information on either class.

Carol Oneal is a past president of the OSU Jackson County Master Gardeners Association. E-mail her at

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