Scorzonera laciniata– I swear this weed is sentient.  I finally took the ShopVac to a south-facing hillside covered with its dandelion-like seedheads, only to have them reappear the next day.  Then the following day, I spent another 30 minutes sucking up fluff…and they reappeared. 

Third day, following a vigorous vacuuming I watched in disbelief as the seedheads that had not yet opened recover the entire hillside slowly over about 4 hours, albeit a bit less dense. 

I’ve pulled it and left on the ground it will go to seed quickly, spreading its seeds as fast and far as the wind will take it.  I’ve mowed it only to have it sprout more stems and flowers at ground level below the mower blade.

Despite its name, cutleaf vipergrass is not a grass.  It’s a broadleaf plant with a non-woody stem that is native to Europe and a member of the Asteraceae (Aster) plant family, as are sunflowers and dandelions. 

It was originally imported for erosion control, and I suspect it was in a grass mix I spread many years ago on this hillside.  It looks and acts a bit like western salsify (Tragopogon dubious), and in fact, one of its alternate common names is false salsify.  

A couple of years ago, I was in the little greenhouse at Ace Hardware shopping deals and a fellow brought a sample of this nuisance to the employee watering plants, asking what it was. 

In recent years the Schutter Diagnostic Lab in Utah has had an increasing number of questions and identification requests related to this plant, mainly from lawn, roadside, and pasture settings. It’s listed as a noxious weed in Utah based on its observed rapid spread in disturbed areas, but not (yet!) in Routt County.  At a recent County-sponsored Weed Day, a group of us marshalled all our plant identification apps to figure out what we were looking at.

Cutleaf vipergrass is a biennial plant, meaning it forms a rosette in the first year and flowers, sets copious seed, and dies during the second year.

Fortunately for those of us tired of trying to interrupt its uncanny ability to grow, it reproduces only by seed and has a narrow pullable taproot. Plants are 6 to 18 inches tall with hollow stems. Bright yellow flowers are about ½-to 2 inches wide and resemble those of western salsify or dandelion.

Each stem has one flower at the end, and the flowers are open for a few hours daily. The flower and seed heads have a teardrop shape. Leaves are often deeply dissected with long, linear lobes. These long narrow leaf segments may resemble grass, leading to the common name, cutleaf vipergrass.  It also has white milky sap, again resembling western salsify or dandelion.  With its leggy, ground-hugging stems, it is not particularly attractive. 

Weeds are a plant out of place – something growing where you either don’t want it or where it will take over and create a monoculture – like white top and field bind weed.  Other weeds are deleterious – poisonous plants like hounds tongue or larkspur on rangeland. 

At CSU, we preach the gospel of integrated pest management – treading as lightly as possible to remove pests and using as few chemicals as possible to control nuisances. Cutleaf vipergrass may be one of those plants, like whitetop or field bindweed, where any bit of the root left in the ground will create a new plant. My best advice is to identify the first-year rosettes or second year flowering plants and pull or mow them when the ground is moist well before they go to seed.  Happy gardening!