June 15. I swat yet another mosquito as I stand waiting in Deerlodge Park on the banks of the Yampa River, watching, as utter chaos unfolds before me. The scene under observation is a mixture of tourists, guides, screaming children, screaming adults, park service personnel and an incalculable amount of gear being tossed from shore to boat. It is my first river trip. Unsure of what to expect (thoughts of mauling mosquitoes, gigantic rapids, and that groover device flitting through my head), I stand in eager anticipation, an armada of butterflies swarming in my stomach as I await our launch. This is no ordinary river trip; this is a tamarisk trip, and we are warriors. We are weed warriors, and our enemy is the dreaded species Tamarix spp. With a group of 20 folks I have met only yesterday, I am about to embark on a six-day journey where we will saw, clip, cut, hack, dig and wrench as many tamarisk plants as possible from the banks of the Yampa. Although I am not 100 percent clear as to what a tamarisk even looks like, I will begin to understand throughout the next six days the scale of Colorado's fight against the tamarisk as well as the multitude of other invasive species that infect the state - and, more importantly, what is being done to combat this problem.
As one of the most troublesome weeds in the west, the tamarisk covers a range of roughly 1.5 million acres of land in the western United States, 7,500 acres alone on the portion of the Colorado River from the headwaters to the Colorado-Utah state line. The tamarisk originated in central Asia and was brought to this country in the early 19th century for use as an ornamental, in windbreaks and for erosion control. It is a deciduous shrub or small tree with an extensive root system that is well suited to the heat, arid climates and alkaline soils common in the western U.S. Studies have shown that in the presence of established native vegetation, tamarisk seedlings are not strongly competitive. Therefore, as long as native plant communities remain intact, tamarisk invasion by seed is not likely to occur. Unfortunately, disruption of native plant communities as a result of natural or human influenced activities will allow new infestations to occur. Once a stand is mature, it will remain the dominant feature of an ecosystem unless removed by human means.
Although tamarisk is the poster child of invasive weeds in the west, Colorado has plenty of other species to deal with, and, more specific to the region of Routt and Moffat counties, troublesome species include but are not limited to: Russian olive, leafy spurge, hoary cress, toadflax and Canadian thistle. These noxious weeds slowly are encroaching on native plant communities and have a multitude of negative biological implications. Generally speaking, these plants are aggressive, possess an ability to reproduce profusely and resist control. These species also threaten wildlife habitat, cause economic hardship to agricultural producers, and are a nuisance for recreational activities.
Fortunately, there is a several-fronted battle going on against the invasion of these nonnative weeds. For example, the efforts of groups such as Friends of the Yampa and Dinosaur National Monument in organizing annual tamarisk trips. For the past several years, this group of Steamboat locals has been dedicated to manually combating the spread of invasive species throughout the Yampa river system. Biological warfare is also occurring as a nonnative beetle (Diorhabda elongate) originating in Asia has been introduced along many of Colorado's rivers with the result that it preys exclusively on the leaves of the tamarisk. Studies have indicated that repeated defoliation will cause the plant to die. In recent efforts, a partnership formed to develop a strategic plan for the Colorado River's riparian areas impacted by invasive trees, principally tamarisk (Tamarix spp.) and Russian olive (Elaeagnus angustifolia). The Colorado Headwaters Invasive Partnership is a statewide eradication plan for the Colorado, Gunnison, Uncompahgre, Dolores, White and Yampa/Green watersheds prepared by the Colorado River Water Conservation District, The Nature Conservancy and the Tamarisk Coalition. The goals and objectives of this plan are basically to control nonnative weed infestations and re-establish local plant and animal communities by providing a mechanism for communication among diverse parties and land managers throughout Colorado's watersheds.
Being a newcomer to this state and essentially the whole concept of invasive weeds in the West, my personal experience throughout the past few months in participating in some of the many facets of the weed solution has been enlightening. First, as a weed warrior in pulling weeds from the banks of the Yampa, spraying and controlling weeds at The Nature Conservancy's Carpenter Ranch and now, doing my part to ensure the success of the CHIP plan in Routt and Moffat counties has given me quite a taste for not only the scale of the weed problem, but also how collaboration, communication, compromise and public awareness are absolutely imperative in accomplishing our goals.
As for my first river trip, well ... let's just say it was six of the most memorable days of my life. I did survive - the bugs, the groover and a nice, long, icy swim through Warm Springs. I took great satisfaction in ripping out as many tamarisk as possible, laughed so hard I cried, hiked, swam and breathed that sweet breath of the river. I am a weed warrior for life.
Lucy Parham is the Carpenter Ranch Outreach and Stewardship Assistant for The Nature Conservancy. To learn about TNC's work in Colorado and around the world, visit www.nature.org.