Using livestock to graze noxious weeds can be an effective option if done correctly. The goal when grazing noxious weeds with livestock is to target the noxious weed(s) while leaving the native vegetation alone so that it can compete with the weeds. Typically, the grazing situation uses a large number of stock for a short duration of time. This may be days or even hours. The livestock are then removed from the area. They can be placed in dry lot pens for several days to allow any viable seed to pass through and prevent it from being deposited else where. After this holding time, the animals can then be moved to other locations. The process is then repeated, grazing - quarantine, grazing – quarantine, etc. The stock can be returned to a previously grazed location if the native vegetation has recovered and the noxious weeds warrant the grazing stress.

Before beginning a grazing program identify what weeds (noxious and otherwise) the stock will be consuming. Most plants have the potential to be toxic. The toxicity may depend on the plant species, the growth stage of the plant, the time of year, weather and on the animal’s physiology.  For instance, some plants are more toxic to horses than to sheep. Some plants are more toxic after a frost. Some plants are toxic to gestating animals. Some plants may cause infertility. Some plants are deadly. Therefore, do your research and determine if grazing the noxious weeds on your property is the best choice for you and them.

When grazing noxious weeds with livestock it is important to monitor the condition of the animals, as well as their physical development. Continue to monitor their body condition even after they are removed from an area. Some toxicity’s are accumulative in nature and may end in death. Some toxicity’s only cause chronic illnesses. It may be necessary to provide various supplements or even additional feed to help support the animals.

The following link is to a program that Utah State University has been working on. They have been evaluating in depth the use of livestock grazing on noxious weeds. The Fact Sheets link under Educational Products is very useful.
http://www.behave.net/

The following link provides a comprehensive list of toxic plants, poisoning symptoms, corrective measures as well as pictures.
http://www.vth.colostate.edu/poisonous_plants/

If you have any questions or need help in identifying the weeds on your property, please call 970-304-6496 ext. 3770 to schedule a farm visit free of charge.

The following link is to a coopertive research project between Nevada, Idaho and Western Region of Sustainable Agriculture Research and Education. The book is called Livestock Grazing Guidelines For Controlling Noxious Weeds In The Western United States. The 80 page book covers 26 weed species, which livestock are best at grazing, timing of grazing and other important information. This is a very useful book when considering grazing your livestock. http://www.unce.unr.edu/publications/files/ag/2006/eb0605.pdf