What grows one to three feet high, has small blue-green leaves, clusters of pretty yellow flowers, and is a stubborn, nasty, and aggressive noxious weed that is supported by an extensive system of underground stems? Probably the only good news is that it isn’t typically a weed in most landscapes, but if you’ve been out hiking much lately, you’ve likely encountered Leafy Spurge.
A weed is…
I subscribe to a variety of online gardening groups, mostly on Facebook. Lately there has been a lot of ranting discussion about whether or not dandelions are weeds. On the one hand, various gardeners are asking for help controlling dandelions in their lawns and gardens, often to please a landlord. On the other hand, various opinionated persons climb onto their soapboxes and extol the virtues of dandelion leaves, wine, and bee-friendly flowers, chastising anyone who would dare to disagree. (more…)
After the storm earlier this week, snow blankets the fields, hiding most signs that anything ever grew there. But interspersed with the even white blanket and occasional dried grass leaves are spikes, sticking up like posts in the empty landscape. We’re finally noticing the dead and dried flower/seed stalks of Common Mullein (Verbascum thapsus).
The flowers could be considered somewhat pretty—a white or lavender tuft reminding me of cornflowers (aka bachelor’s buttons). The somewhat pretty flowers are probably the only positive aspect of these plants. A common noxious weed, knapweed is the bane of my garden.
The problem is that we live immediately adjacent to an open space, a few supposedly wild acres left by the developer (probably because it’s too steep to build on). There’s Gambel’s oak, six Ponderosa pines, a smattering of yucca, assorted wildflowers, and some rather nasty weeds.
Most of us are familiar with teasel. It grows in most states, including Colorado where it is designated a “List B” species in the Colorado Noxious Weed Act. That means that, if you live in Colorado (or several other states), you need to declare war on any plants on your property. Good luck.
Teasels are easily identified by the spiny flower head left behind after the petals have fallen, as you can see in these photos. There are two species listed as noxious weeds in Colorado—the Common Teasel (Dipsacus fullonum), shown, and its lookalike cousin Cutleaf Teasel (Dipsacus laciniatus).
Fresh as a daisy. Daisy chains. “The daisy’s for simplicity and unaffected air.”*
Symbols of simple charm, it’s hard to imagine that daisies could be anything but pure and innocent. Yet, the familiar Oxeye daisy has a dark side. Under that attractive and cheerful guise lurks… a noxious weed!
Take a trip to the mountains to see the wildflowers, and you’re bound to see Oxeye daisies as well. They’re all over the Rockies, preferring the higher elevations. Unfortunately, they don’t belong here. They’re native to Europe, and we heartily wish they had stayed there!
Spring flowers are finally filling the fields. Milk vetch, penstemons, wild onions and marsh marigolds all caught my eye as I hiked though the towering cottonwoods along Fountain Creek, at the base of the Rockies here in central Colorado. I was particularly impressed by huge swaths of a foamy white flower I didn’t immediately recognize.
Counting the petals—each tiny flower had four—and examining the foliage led us to conclude the plants were Crucifers, members of the mustard family. Sure enough, we were enjoying the pretty flower heads of Whitetop (Cardaria draba), an aggressive import from Europe and Asia that is listed as a noxious weed here in Colorado (List B). Oh dear.
I recently read a confounding article on Garden Rant (a gardening blog like no other). The author was reporting on some new research suggesting that not all invasive species should be eradicated.
Specifically, a Penn State biologist named Tomas Carlo studied Japanese Honeysuckle (considered a noxious weed in much of the eastern US) and found that its presence increased the biodiversity of bird species as well as the number of individual birds. In fact, the fall berries are a major source of food for fruit-eating birds.
Mountain Plover 