Saturday, June 26, 2010
Yucca Whipplei--Our Lord's Candle
Those creamy flowers are so beautiful against the white clouds and blue sky. See it today at the UC Botanical Garden. Supposedly the plant dies after it flowers, so maybe this will be your last chance to see it for awhile. Yuccas are pollinated by Yucca Moths (Tegeticula spp.). The plants can't set seed without the Yucca Moth, and the Yucca Moth caterpillars have nothing to eat unless the seeds develop, because that is the only thing they will eat. So these two organisms are dependent on each other. A female Yucca Moth gathers a ball of pollen. She pierces the ovary and lays one egg. Then she stuffs the pollen ball into stigma. The pollen grains grow down the stigma and into the ovary where they fertilize the seeds. The fertilized seeds grow, providing food for the larva, but not all are eaten. The uneaten seeds become the next generation of yuccas. For a more thorough explanation, read Waynes Word: http://waynesword.palomar.edu/ww0902a.htm. The flowers are lovely, yes, but the plant/insect interaction is amazing!