Foxtail is a common annual grass weed found in hayfields across many regions, often thriving where desirable forage grasses have thinned out. Species like Yellow, Green, and Giant foxtail are fast-growing and reproduce prolifically, frequently contaminating hay harvested late in the season. Identifying foxtail in baled hay is crucial for livestock owners, especially those who feed horses, to protect animal health.
The Physical Danger of Foxtail Contamination
The danger associated with foxtail consumption stems from the structure of the mature seed head. These plants produce sharp, rigid bristles known as awns, which are barbed spikes attached to the seeds. When an animal consumes contaminated hay, the awns readily break off and embed themselves into soft tissue.
The barbs prevent the body from easily dislodging them. Awns commonly lodge in the gums, tongue, lips, and cheeks, causing mechanical irritation and inflammation. This constant irritation can lead to painful lesions, ulcers, and deep-seated abscesses in the oral cavity. Awns can also migrate into the eyes or nasal passages, causing localized infections and discomfort that makes eating or drinking difficult.
Detailed Identification of the Foxtail Seed Head
The seed head is the most recognizable part of the foxtail plant, often described as resembling a dense, cylindrical brush or a fox’s tail. When dried and mixed into hay, these structures typically appear as stiff, straw-colored or tan clusters. The overall shape may range from an erect spike to a distinctive arching or nodding form, especially in varieties like Giant foxtail.
Close inspection reveals the numerous, sharp awns radiating outward from the central axis. These bristles give the dried foxtail its characteristic bristly texture. In Yellow foxtail, the awns often take on a noticeable yellow hue when fully mature and dried, making them stand out against green or brown hay.
Since these seed heads are fragile when dry, look for individual, shattered awn fragments embedded deep within the hay bale. Even without the full head, these stiff, sharp fragments maintain their barbed structure and pose a risk upon ingestion.
Recognizing Foxtail Stems and Leaves in Dried Hay
While the seed heads are the primary danger, the vegetative parts offer clues for identification, even when dried. Foxtail grasses possess a structure in the collar region—the junction where the leaf blade meets the stem. Unlike desirable hay grasses, such as Timothy, foxtail species feature a fringe of fine hairs in this area instead of a tall, membranous ligule.
The leaf blades show distinguishing characteristics among varieties. Giant foxtail leaves are noticeably wider, often measuring between 3/8 and 5/8 of an inch, and may have a fine, dense layer of hair on the upper surface.
Yellow foxtail can be identified by sparse, long, silky hairs located near the base of the upper leaf surface. Additionally, the stem base of Yellow foxtail is often flattened near the soil surface, contrasting with the round, cylindrical stems of Green and Giant foxtail.
Immediate Action When Foxtail is Found
Upon confirming foxtail seed heads or awn fragments in a batch of hay, isolate the contaminated forage immediately. Do not feed any hay from the affected bale or stack until the extent of the contamination is known. Contact the hay supplier promptly to report the issue and request a replacement of the contaminated bales.
If an animal has already consumed the hay, monitor them closely for signs of oral discomfort, such as refusing to eat, excessive salivation, or reluctance to chew. Any animal showing these symptoms should be examined by a veterinarian, as removing embedded awns may require sedation and specialized instruments. Discarding the contaminated hay is the safest course of action to prevent further injury to livestock.