Controlling Noxious Weeds

Now that the soil has been softened by fall rains, it is time to tackle some of the invasive weeds trying to overtake our yards and parks. One of the most easily identified is English Ivy, which was originally brought over from Europe to “green up” our fair city after the clear cutting in the early 1900’s.

It quickly became a pest, invading vacant lots and parks and attacking trees. It can be controlled by constant maintenance; with annual shearing, it can be a tolerable ground cover. But without a gardening staff to maintain it, it becomes a hazardous invasive, because it wants to climb upon every bush, shrub, tree and building. It flowers and produces berries which are transported by our avian friends to other areas. “Down with English Ivy” should be everyone’s mantra!

Another noxious weed in our midst is wild clematis, sometimes called “old man’s beard”, because of the tiny puff balls of seed pods it produces. These become airborne in winter and spring, sprouting everywhere. Wild clematis is also an aerial climber, like English ivy, and with time, it produces tarzan-like cables. In big winds, these cables act like sails, capable of bringing down full-grown trees.

Both ivy and clematis are fully controlled only by digging, but the roots can reach sizable proportions. Other invasive weeds that need controlling include Himalayan blackberries, Herb Robert (also called Stinky Bob) and Japanese knotweed to name a few.

It is possible to learn more about these weeds and recommendations for control by contacting the King County Noxious Weed Control Program at 206.296.0290. Washington State Noxious Weed Control has an illustrated booklet identifying noxious weeds. Call 360.725.5764 to order PUB 820-264W (n/6/09) or go to nwcb.wa.gov.