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Small cactus hairs like to bury themselves in fabric, making them incredibly difficult to remove. However, you can usually get a large portion of them out using duct tape or a similarly strong adhesive. To do so, cover the affected area with a strip of tape, then rip the tape off. Repeat this multiple times for the best results. Do not use this method on your skin. Doing so may cause additional damage to the stabbed area. Unlike small needles, large cactus spines and ball-like hitchhikers are easy to remove from clothing. To do so, grab a fine-toothed comb and place it just above the needles. Then, run the comb down through the needles to brush them off.  Once you’ve removed most of the needles, get rid of any stragglers using duct tape or a pair of tweezers. When combing, make sure to keep you hand as far away from the needles as possible. Once you’ve removed as many needles as you can, place your clothing items in a washing machine and run them through a normal cleaning cycle. Doing so will remove any small hairs you couldn’t get out by hand. Do not wash your affected clothes with other garments, otherwise you may simply move the cactus needles from 1 item to another.

Summary:
Remove small cactus needles using duct tape. Pull out large cactus needles with a comb. Clean your clothes in a washing machine to remove leftover needles.