Guest Column

Be on the lookout for toxic weeds that are sprouting up

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Poisonous weeds in the Western United States cause millions of dollars of damage each year. According to an article written by Raylene Owen, Elbert County master gardener, the weed problem is primarily due to overgrazing, disturbing the land and overuse of livestock on rangeland and pastures. Overgrazing reduces the more palatable and desirable plant varieties, leaving the less palatable and possibly poisonous plants and weeds. Removal of more desirable plants also leaves bare soil, contributing to soil erosion by both wind and water.

This is the time of year to start looking for death camas emerging from the soil in Elbert County pastures. It looks a little like garlic when it first starts to grow. Death camas is a native perennial found in the Western two-thirds of Colorado at elevations of 4,500 to 8,000 feet. A couple of years ago, I found death camas in my neighbor's pasture across the road from me. With proper precautions, we were able to dig the plants out and dispose of them safely.

A common species in the Elbert/Douglas counties area is meadow death camas. This hairless herb has grass-like leaves that are up to 12 inches long and can grow 8-14 inches tall. It blooms with greenish-white, cream, or yellow blossoms. The bulb is onion-like with a dark brown outer paper-like husk.

There are several species of death camas and all should be considered toxic. All parts are toxic including the leaves, flowers, bulb and pollen. The toxin in the plant is a steroidal alkaloid, zygacine. Death camas is often one of the first plants to emerge from the ground in the spring before other forage is available. If consumed, it is toxic to livestock, as well as people and pollinating insects. Sheep are most susceptible, followed by cattle, then horses.

Contaminated pastures should not be grazed by sheep until later in the spring when more forage becomes available. People have mistaken the bulb for wild onion (even though it has no onion odor), eaten the bulb and died.

Seeds are the most toxic, but are rarely eaten as they are dry and unpalatable. Next most toxic is the bulb, but it is rarely pulled out of the soil and eaten since it's buried 6-8 inches deep. The leaves are next in toxicity and are most likely to be eaten. Do not cut infested areas for hay, as dry leaves in hay retain their toxicity. There are no good medicinal remedies, but poisoned animals that are cared for and kept quiet may recover.

Some symptoms of ingestion include slobbering and vomiting, cyanosis, followed by weakness, staggering and convulsions, then coma for several hours or days followed by death.

For more information on how to control the death camas and to view photos, go to http://elbert.extension.colostate.edu/programs/gardening-horticulture/.

Elbert County Extension is a cooperative effort between CSU Extension and Elbert County government. Sheila G. Kelley is the Colorado State University extension director for Elbert County. She can be reached at sheila.kelley@colostate.edu.

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