Yes. In hard times, elk will consume plants that do more harm to them than good. In the winters of 2004 and 2008, elk in southern Wyoming ate poison lichen that led to muscle weakness, nerve damage and the eventual deaths of more than 600 animals. The state reports that in fall 2012 elk died of lichen poisoning as well, and they have put out an alert to watch for more. Locoweeds are found in nearly every state west of the Mississippi and contain a chemical substance similar to morphine, producing symptoms of lethargy, incoordination and sometimes blindness and death. Juniper and some varieties of sagebrush contain antimicrobials called terpenoids, which can kill intestinal flora that break down cellulose, thus inhibiting the elk’s ability to digest forage.
So, why do elk consume these plants? Sometimes they have no choice. During times of drought, harsh winters or poor range conditions, the delectable and healthy grasses and forbs elk love may not be available. Even the less nutritious browse that elk depend on during winter may disappear leaving hungry elk with a few unsavory options.