Yucca Plant

By William T. Hathaway

Yucca Plant (Yucca filamentosa)

The Yucca or Spanish-bayonet (Yucca filamentosa) flowers are pollinated only by the Yucca Moth. Without these moths, flowers cannot form seeds and plants can only reproduce by root offshoots. The tiny female moths make a sticky pollen mass from one flower and carry it to another yucca flower. Pollen masses touch the stigma of the new flower as she inserts her eggs into the ovary. Her larvae develop in the ovary and feed on the seeds. Since there are many more seeds than larvae, perpetuation of the yucca plant is assured. This is a mutual benefit to both the plant and moth.

On local field trips during late April and early May it has never failed to surprise students, when shaking a cluster of yucca flowers resulted in a flittering swarm of elfin moths. Can you see a couple of moths in the picture?