Yucca

Yucca is a genus of perennial shrubs and trees in the family Asparagaceae, subfamily Agavoideae. Its 40–50 species are notable for their rosettes of evergreen, tough, sword-shaped leaves and large terminal panicles of white or whitish flowers. They are native to the hot and dry (arid) parts of the Americas and the Caribbean. Early reports of the species were confused with the cassava (Manihot esculenta). Consequently, Linnaeus mistakenly derived the generic name from the Taíno word for the latter, yuca (spelled with a single 'c'). It is commonly found growing in rural graveyards and when in bloom the cluster of (usually pale) flowers on a thin stalk appear as floating apparitions. The natural distribution range of the genus Yucca (49 species and 24 subspecies) covers a vast area of the Americas. The genus is represented throughout Mexico and extends into Guatemala (Yucca guatemalensis). It also extends to the north through Baja California in the west, northwards into the southwestern United States, through the drier central states as far north as southern Alberta in Canada (Yucca glauca ssp. albertana). Yucca is also native to some of the Caribbean Islands, northward to the coastal lowlands and dry beach scrub of the coastal areas of the southeastern United States, along the Gulf of Mexico and South Atlantic States from coastal Texas to Maryland. Yuccas have adapted to an equally vast range of climatic and ecological conditions. They are to be found in rocky deserts and badlands, in prairies and grassland, in mountainous regions, in light woodland, in coastal sands (Yucca filamentosa), and even in subtropical and semitemperate zones, although these are generally arid to semi-arid. Yuccas have a very specialized, mutualistic pollination system, being pollinated by yucca moths (family Prodoxidae); the insect purposefully transfers the pollen from the stamens of one plant to the stigma of another, and at the same time lays an egg in the flower; the moth larva then feeds on some of the developing seeds, always leaving enough seed to perpetuate the species. Certain species of the yucca moth have evolved antagonistic features against the plant and do not assist in the plants pollination efforts while continuing to lay their eggs in the plant for protection. Yucca species are the host plants for the caterpillars of the yucca giant-skipper (Megathymus yuccae), ursine giant-skipper (Megathymus ursus), and Strecker's giant-skipper (Megathymus streckeri).