The Enemy: Poinsettia (Euphorbia pulcherrima)
Strategy: During the 14th to 16th centuries, the sap was used to control fevers and the bracts (modified leaves) were used to make a reddish dye. Joel Roberts Poinsett was the first U.S. ambassador to Mexico, being appointed by President John Quincy Adams in the 1820s. In 1828 he found a beautiful shrub with large red flowers growing next to a road. He took cuttings from the plant and brought them back to his greenhouse in South Carolina. Even though Poinsett had an outstanding career as a U.S. congressman and as an ambassador, he will always be remembered for introducing the poinsettia into the United States.
Attack: Poinsettias normally do not become a weed, especially because they do not adapt to our regions, although many are grown in geothermal greenhouses near McCall. The milky sap, as with all Euphorbias (Leafy spurge) can be toxic and cause skin and eye irritations, especially in children. It has been known to be a weed where it grows as a shrub in Mexico along roadsides and causes problems similar to brush species in the United States.
Defense: Most people here simply throw them away. Women purchase 80 percent of the poinsettias bought in the U.S. Of these most are the red variety. If it does become a problem, simple mechanical control is available. If you have had them in your house for a while, you may find a white fly that likes to attack them and other plants. Simple herbicides such as 2,4-D will take the plant out as long as you spray it early in the season. As with other weeds, you know — a plant out of place — proper identification is key to controlling it.