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If I don’t have a field guide with me, how can I tell if a plant is safe to eat?
– Caleb Gordon, via email
Plan A: Stick with what you know. Odds are, you’re familiar with yard plants—clover, dandelions, and chickweed—and other common edibles.
Plan B is a song and dance we call the Universal Edibility Test. If you’re an impatient eater, beware: this is not a quick process.
First rule out known baddies like poison ivy, then wildcards like mushrooms, many of which can kill you in just one bite. About 95 percent of all other plants are at least partially edible, according to North Carolina foraging instructor and author Alan Muskat. Even so, don’t go munching willy-nilly without expert supervision unless you’re really starving.
Divide a plant into leaves, stems, and buds, and test each separately. Nix anything with a foul odor or pale, milky sap. Next step: Touch a small piece to the inside of your arm. If you’re reaction-free after 15 minutes, try your lip and wait again. Tongue’s next. If there’s still no reaction, ingest a small piece and wait eight hours. Getting ill? Bring it back up til your stomach’s empty. If you’re symptom-free, try a small handful. Feel good after eight more hours? Green light.
UV purification pens are pretty effective. Can I achieve the same
effect using sunlight?
– Shelby Terraza, via email
All UV rays destroy pathogen DNA, but unlike an easy-to-use Steripen, sunlight takes some coaxing. Grab a clean, clear plastic bag or bottle. A new PET water or soda bottle works best. A clear Nalgene will do if it’s not too scratched up: Without near-perfect transparency (of both water and plastic), the sun can’t do its job.
To test, try to read the large text in your guidebook through the bottom of your bottle. No dice? That means the UV can’t penetrate. (Strain murky liquid through fabric.) When all’s clear, find direct sunlight. Lay the bottle on a dark surface and hunker down; zapping germs this way takes at least six hours. If over half the sky is gray, wait a full 48 hours. If the whole business is cloudy? Best work on your rain dance.