Battle against invasive weeds goes regional

Battle against invasive weeds goes regional
Posted on 06/30/2016

Regardless of how pretty they might be, invasive weeds are no joke. Rod Cook, La Plata County’s weed manager knows this both in theory, and on the ground. And his newest enemy, the oxeye daisy, is among the most formidable given its friendly face. After all, what could be wrong with a flower long honored in song, chains, and names – among other cultural threads? As it turns out, plenty.

The oxeye daisy, despite its innocent bright yellow-and-

white appearance – is actually an aggressive invader, taking over alpine meadows at near warp speed and leaving what Cook calls a “biological desert” in its wake. Pollinators don’t like the flowers, nor do grazing animals, so oxeye daisies propagate unabated through formerly diverse fields, painting them white with abundant flowers.

The problem is quite literally growing exponentially. Cook says that there are 1,500 acres of oxeye daisies in La Plata and San Juan counties, and much of the infestation is on federal lands. With a spread rate of approximately 50 percent a year, oxeye daisies are threatening to drastically change the landscape in oxeye daisy in harris parkSouthwest Colorado – throughout many jurisdictions.

Cook and Ron Mabry, his counterpart for Ouray and San Miguel counties, convened a group that aims to do just that throughout Southwest Colorado. The San Juan Mountains Cooperative Weed Management Area is a multijurisdictional collaboration that pulled together to make best use of the limited resources each entity has available to fight weeds – largely oxeye daisy – in the region. The U.S. Forest Service, Colorado Department of Agriculture, Mountain Studies Institute and local volunteers have united in a common effort, albeit a huge and growing one. Given the free-wheeling nature of the oxeye’s spread –combined with limited resources at the local, state and federal levels to fight the weed - a regional collaboration is the only hope of getting a handle on the plant’s infestation.

The goal is as ambitious as the resources are limited, and the collaborative aims to first contain and curtail new infestations of oxeye daisy while simultaneously studying the best treatment options for widespread eradication. A third prong is to work with property owners and businesses – ski areas in particular – where oxeye daisies are setting up shop. Eliminating large plots of the daisies will be challenging: herbicide costs are about $85 an acre to effectively treat the weed; at 1,500 acres and growing, the problem would require $127,500, to say nothing of staff and equipment time in applying the treatment. young oxeye daisy leaves

The collaborative group is working around the edges, then, deploying teams of trained applicators to tackle the oxeye throughout the region. Additionally, Cook and Mountain Studies Institute are setting up test plots on Coal Bank Pass to study the effectiveness of various treatments: herbicides, hand-pulling, mulching, re-seeding and combinations thereof. By gathering data on how the weeds respond to these methods, the group can then inform the next phase of its attack plan.

To find out more about invasive weeds and how to manage them – or to get involved with the oxeye daisy project – contact Rod Cook at (970) 382-6470 or