Between Urban and Wild: Reflections from Colorado

Weed Duty

103 Weed Duty By late spring, the season is in full swing. Weeds get an early start, even at this high elevation. As soon as their green shoots are large enough to be identifiable, I start pulling and I’ll spend a few hours a week at this task right on into fall. Some of my weeding is more puttering than sustained effort, plucking a seedling here and there when I step out of the house for a few minutes or when I’m walking to or from the barn. Beyond the driveway, I make more dedicated expeditions , thinning the nearby roadsides of pennycress, pepperweed , hoary cress, thistles, sticktights, and tumbleweed. One of the old-timers who lives nearby scoffed when I moaned about the weeds, telling me, “Mother Nature will take care of them.” I respect his judgment; his family homesteaded here in 1917, and he spent his whole life in these hills. But I pull weeds anyway. It’s true that Ma Nature is good at keeping her house in order, but we humans exhibit a talent for interfering with her domestic routines, and there are a lot more of us in her abode these days. Out in these parts, people weed duty 104 are apt to cut roads for driveways and bulldoze ground for houses and outbuildings. Every patch of disturbed earth harbors banked weed seeds, just waiting for the opportunity to sprout. We haul in gravel to maintain the roads and hay to feed our hobby livestock, and each load carries in undesirable seeds. We pretty things up with landscaping or a garden, importing exotic and occasionally aggressive plants. In this dry country, it doesn’t take long for a few too many horses or llamas to overgraze a pasture, creating conditions that only a weed could love. A weed is a plant that’s not desirable in the place it’s growing , so categorizing plants as weeds is a matter of context and opinion: a subjective judgment. The dandelion blooming on a lawn or golf course offends by disrupting a uniform carpet of turf. The aster in the rose garden or the grass in the perennial border or the squash plant springing up in the lettuce row violate our sense of order or composition. Human aesthetics can cut the other way with weeds, too, favoring their spread as well as their condemnation. A number of the most notorious weeds in the United States enter new habitats as ornamentals, deliberately planted and nurtured in new locations. When purple loosestrife, toadflax, dame’s rocket, or bachelor’s button escape the controlled habitat of the yard or garden, they can wreak ecological havoc. Free of the competitors, foragers, and pests of their homelands, such plants display an aggressive exuberance. They spread out of control, colonizing ground occupied by the native plants that sustain the local fauna or livestock grazing. Weeds don’t have to be intentionally cultivated to be a problem, of course, and crowding out forage plants is not their only offense. Bromus tectorum, aka cheatgrass, came to the West from the Mediterranean, most likely first arriving as packing material. In addition to a propensity for spreading quickly, it’s a notorious fire hazard. Cheatgrass greens up weed duty 105 early in the spring, absorbing water before native plants are ready to use it, then dries out quickly and catches fire easily. Surviving seeds can sprout in the ash that same year, ready to start the cycle over again the following spring. After a few repetitions of this pattern, even deep-rooted perennials may succumb to a newly established fire regime. When nonnative plants are so badly behaved that laws are written in an effort to control them, they are labeled as “noxious.” These plants earn their title both by spreading­ aggressively—­ some knapweeds emit chemicals through their roots that inhibit the growth of other plants, and leafy spurge develops tight seed capsules that pop open with enough force to eject seeds up to fifteen feet from the parent ­ plant—­ and by being difficult to control. Canada thistle spreads by way of windborne seeds, but also from root nodes, each of which is capable of developing into a new plant. Tilling a stand of Canada thistle, ­ then—­ or running through a roadside patch with a ­ grader—­ amounts to planting a new crop. Many plants are also considered weeds because they lack value as, or compete with, livestock forage. This criteria makes many native plants, despite their beauty...