In my Docent studies I've been trying to learn all the plants in our yard. It's a big yard--nearly an acre--and there are a lot of shrubs, scrubby plants and trees that I can't identify yet. Among the things I can identify are a barrel cactus (fishhook barrel) which actually is crestate (see picture) and a yucca, which I believe is soap-tree yucca, a plant that had great value to the native Americans and the Tohono O'odham. It served as a source of soap, fiber, and basketry. In the spring it has spikes of gorgeous creamy white flowers.
Many yuccas are fertilized by a tiny moth that flies (at dusk) from flower to flower, gathering pollen in a little ball that she carries under her head. When she has created a pollen ball BIGGER than her head, she chooses a flower to fertilize. First, she cuts a hole in part of the flower's ovary apparatus and lays her eggs. Then she crawls up the stigma of the flower and deposits her ball of pollen. The pollen fertilizes the flower, and when the moth eggs hatch the larvae have plenty of seeds to eat. But they only eat a few of them, so the yucca is able to reproduce also.
I continue to sleep happily surrounded by lots of roosting quails.