Sally – The most lyrical description of the relationship I’ve read was Chris Clarke’s essay in the Insecta issue of qarrtsiluni, which focused specifically on the Joshua tree (a type of yucca, of course): Yucca Moths.

Fred – Of course yuccas do flower here, they just don’t set seed. From what I could gather on the web, I think this cultivar is most likely a species native to the southeast, where it was spread around by the Indians who grew it for fiber (those filaments) and soap (the roots).

brendanblue – sometimes I think deserts make the best natural gardens: hardly anything looks like a weed! Well, except for all the invasive grasses and thistles.

Shai – Thanks for the interesting exegesis. I think it shows that by focusing on concrete particulars, a poem can often gain more resonance than if it tries to remain non-commital enough to serve as an extended metaphor. The seeds of the universal germinate in the particular, or something like that.

It seems to me that the image of a plant removed from its native ecological milieu and turned into what ecologists call an exotic is not only an important subject in its own right, but rich with lessons for human beings as well. Plants that — unlike yuccas in the northeast U.S. — are able to reproduce effectively in their new environments so often become horribly invasive, crowding out the natives, because they are liberated from all the checks and balances of their own native environment. But eventually, maybe in a hundred years, those diseases and insect predators will catch up with them, and they’ll start acting more like natives in their new land. (Of course, they may have driven several rare species to extinction by then.)

(You had actually mixed blockquote and link tags in your first comment.)