Yucca Moths

If you’ve spent much time in western North Dakota, you’ve probably run across yucca (Yucca glauca). This is the time of year that yucca are blooming. If you get a chance to look inside some of a yucca’s flowers, there is a good chance you’ll find one or more of these little moths. This is a yucca moth (Tegeticula yuccasella). Yucca moths provide a critical service to yucca plants as they are the yucca’s only pollinator. In return, yucca larvae feed exclusively on yucca seeds (yucca moth adults do not eat at all during their short existence). To avoid laying so many eggs in a flower that most or all of the seeds are eaten, female moths mark flowers they visit with a pheromone. This is believed to cause other females to either lay no or fewer eggs in the marked flower.