Trichogramma wasps kill off over 200 kinds of destructive caterpillars. This feature makes them the most popular bio-control in the world. Although referred to as wasps, they never sting. They are so tiny (1/50-inch from wingtip to wingtip) you will likely never even notice them! These wasps work by laying their eggs inside moth eggs. This kills the caterpillar before it even has a chance to develop. Instead of a caterpillar, another trichogramma wasp hatches and repeats the cycle. Trichogramma development â€” from egg to adult â€” typically takes 8 to 10 days. The wasps live another 8-10 days as adults. During this period, each trichogramma female eliminates as many as 100 pest eggs. For best results, release the trichogramma when the moths first appear. Continue further releases weekly or bi-weekly while moths are present. Nature's Control packages these wasps as ready-to-hatch eggs. They glue 3,000 eggs to a small piece of cardboard. The eggs, which are extremely tiny, hatch within a few days. All eggs usually at the same time. A 16X magnifier allows you to view this process. To delay hatching, keep the eggs in the fridge for a couple of days. To speed up the process, keep the eggs in a warm room. As soon as the eggs hatch, wedge the cards among plant foliage. You can also staple them to leaves or branches. For best results, release the hatched wasps in the early morning or evening. The wasps fly out from there, searching a large area in which to continue the process. If using multiple cards, space them evenly throughout the crop area. This product ships directly from the supplier. This product can only be shipped ground to customers in OR, NM, Northern WA, and Southern CA. This product ships 2nd day air to all other addresses to best ensure survival of the insects.