Pherocon AM No-Bait Sticky Traps provide pest managers, farmers and consultants with an early-warning system to avoid insect damage by monitoring key pests and tracking their migration into non-infested areas. Insects are attracted to the bright yellow card become trapped in the sticky coating. This determines when pest movement begins and when to time treatments. Place traps in the perimeter of your rows or greenhouse. Use for: Citrus Psyllids, Corn Rootworm, Flea Beetles, Pear Thrips, Greenhouse Whitefly, Walnut Husk Fly, Fungus Gnats and Aphids. Replace every two to three weeks outdoors. Package of 25 traps. Traps measure 9" x 11" unfolded with a 7" x 9" sticky grid. Made in the USA.