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Foxtail Alert in Boulder: The Hidden Springtime Danger for Dogs

A Silent Threat Growing in Boulder’s Trails and Fields
As the grasses in Boulder County dry out in the spring and early summer, a natural but dangerous threat begins to emerge—foxtails. These barbed grass awns may look harmless, but for dogs, they can cause severe injuries and even life-threatening complications. Found along trails, in open fields, and even in some neighborhood parks, foxtails are especially prevalent in South Boulder, Marshall Mesa, North Boulder trails, and the areas surrounding Boulder Reservoir.

What Are Foxtails?
Foxtails are the seed heads of certain grasses—like wild barley—that break apart easily and are designed to burrow into the ground. Unfortunately, they don’t just burrow into the soil—they can burrow into your dog’s skin, ears, eyes, nose, and paws, causing infections, abscesses, and in extreme cases, requiring surgery.

A close-up of a golden foxtail in Boulder, Colorado—beautiful but dangerous for dogs during spring and summer hikes

Why Boulder Dogs Are at High Risk
With Boulder’s abundance of open space and dog-friendly areas, pets are frequently exposed to foxtails, especially when off-leash. Dry, grassy areas that haven’t been mowed recently are the biggest hotspots, with places like Chautauqua Park, Shanahan Ridge, and trails near Wonderland Lake seeing yearly increases in foxtail growth during the warmer months.

Symptoms to Watch For
If your dog is frequently licking a paw, shaking their head, sneezing excessively, or showing signs of discomfort after a hike, a foxtail may be the culprit. Prompt vet attention is critical, as foxtails can travel internally and lead to much more serious problems.

How to Protect Your Pup

• Avoid tall, dry grasses during peak foxtail season (late spring to early fall)

• Inspect your dog after every outdoor adventure—especially in the ears, paws, nose, and underbelly

• Consider using protective gear like booties or dog snoods on high-risk hikes

• Keep your yard trimmed and check for foxtail growth regularly

Boulder Vets See a Spike Every Season
Local veterinarians report a sharp increase in foxtail-related cases each spring. The cost, pain, and recovery time for your pet can be significant, making prevention key. This is especially important as more new residents and first-time dog owners explore Boulder’s trails.

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