Don't let puncturevine hitch a ride on your pants, warns National Park Service

The National Park Service is warning hikers to watch out for seed pods from invasive plant species, which can easily spread after becoming stuck on hiking pants and shoes when walkers are exploring in the fall. 

Canyonlands NPS posted a Tweet showing how to recognize the small, spiny pods of puncturevine (also known as goathead), and encouraging park visitors to clean their gear carefully to avoid spreading the weed on their clothing.

Puncturevine is a broad-leafed summer annual that's classified as a 'noxious weed' by the University of California's Integrated Pest Management Program. The spiked seed pods are sharp enough to injure people and animals, or even puncture bike tires (hence the plant's name). The leaves also contain compounds called saponins that can be toxic to livestock.

Puncturevine fruit are round with five lobes, and measure around 1/5in to 2/5in in diameter. They vary in color from gray to yellowish tan. When the fruit is mature, the lobes separate into 'nutlets', each of which has two sharp spines and several short prickles. Nutlets contain three to five seeds each.

PlayCleanGo, an awareness campaign run by the North American Invasive Species Management Association, advises you to remove plants, animals, and mud from your clothing, equipment, and vehicle; clean your gear before entering or leaving a recreation site; stick to designated roads and trails; and only use certified local firewood and hay rather than bringing in materials from outside the area.

Specific tips for hikers include picking seeds and burrs off your hiking boots, and brushing them down at designated stations, and using coconut oil to help ease stubborn seed pods out of your dog's coat.

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