Press Release
Eddy County Cooperative Extension Service
1304 West Stevens
Carlsbad, NM 88220
For More Information, Contact:
Woods Houghton, Eddy County Agriculture Agent
Eddy County Cooperative Extension Service
Phone: 505-887-6595 Fax: 505-887-3795
whoughto@nmsu.edu
FOR IMMEDIATE RELEASE
GOLDEN ROD POISONING
I am getting lots of reports of horses and cattle getting the trembles. This is a sign in goldenrod poisoning. So far in
Eddy County I know of 2 horse deaths and lots of sick animals. This is not the first time to have such a rash of
problems with this weed. It happen when it snows and this is what is stick up out of the snow. Here is some
information you need to know.
Rayless goldenrod (Haplopappus heterophyllus), rosea, or goldenrod or jimmy weed, is an erect, bushy, unbranched
perennial shrub, growing from 3 to 4 feet tall. The leaves are alternate, linear, and sticky, and the flowers are yellow.
It is toxic to horses, cattle, sheep, and goats. The reported toxic substance, trematone, is the same toxin found in
white snakeroot (Eupatorium rugosum), a common poisonous plant in the Ohio river valley and eastern United
States. Trematone is excreted in the milk of lactating animals so that the young may become poisoned by the
consumption of contaminated milk (milk sickness). The toxin is present in both green and dry plant material.
Where and When It Grows
This shrub grows on the dry rangelands from southern Colorado into Texas, New Mexico, and Arizona. It grows
especially well in river valleys and along drainage areas. Poisoning is most common in late fall and winter, particularly
after snowfall that covers other forage. It is often planted as an ornamental along highways in Northern New Mexico.
How It Affects Livestock
Daily consumption of 1 to 1.5 percent of an animal's weight of the green plant for 1 to 3 weeks will produce signs of
poisoning in horses, cattle, and sheep. Death will result if the affected animals are not removed from access to the
plant early. The condition it produces in all livestock is known as trembles. As the toxin is secreted in milk, nursing
young may become poisoned by consuming milk. The dam may not show any signs of poisoning when grazing
goldenrod. The animal may not show signs of poisoning until they are moved or exercised.
Signs and Lesions of Poisoning
 Lassitude and depression
 Stands in a humped-up position; stiff gait when walking
 Trembling of muscles of nose and legs, especially after exercise; as the condition
worsens, the whole body may shake
 Weakness
 Constipation and dribbling of urine
 Recumbency
 Acetone odor on the breath
 Coma
 Terminal respiration consists of prolonged inspiration, a short pause, and forced
expiration
 Death
 Myocardial necrosis and fibrosis of cardiac and skeletal muscles
 Degenerative changes of the liver
How to Reduce Losses
If you have an animal that show symptoms, try not to move or excite the animal and feed good quality hay for up to
10 weeks. Treat with mineral oil and activated charcoal if possible to move the toxic weed out of the digestive system
as soon as possible. Consult with your Veterinarian immediately after seed symptoms. Poisoning of livestock by
rayless goldenrod can best be prevented by preventing livestock from grazing on ranges infested with this plant for
extended periods. Rayless goldenrod can be controlled by a number of herbicides picloram or dicamba and
milestone in late summer following adequate rainfall. Follow precautions for handling herbicides. Eddy County
Extension Service, New Mexico State University is an equal opportunity/affirmative action employer and educator. All
programs are available to everyone regardless of race, color, religion, sex, age, handicap, or national origin. New
Mexico State University, U.S. Department of Agriculture, and the Eddy County Government Cooperating
Eddy County Extension Service and New Mexico State University is an equal opportunity employer and
educator. Eddy County Government, New Mexico State University and the U.S. Department of Agriculture
cooperating, to put knowledge to work.
Woods E. Houghton
Eddy County Agriculture Extension Agent
1304 West Stevens
Carlsbad, NM 88220
Office phone: (575) 887-6595
Cell phone: (575) 361-2852
E-mail: whoughto@nmsu.edu
Web page: http://eddyextension.nmsu.edu