Plants of Palermo: 'Desert Museum' Palo Verde trees

This site has been highlighting some of the plants on the city's approved landscaping plan for Palermo Palm Springs. Our Feb. 24 posting looked was the "agave desmettiana" that is now flowering our the development. Our March 30 posting focused on the "bougainvillea oh la la" plant. Today we're looking at the hybrid Palo Verde trees. The scientific name is Cercidium h. Desert Museum, because it was developed at the Arizona Sonora Desert Museum in Tucson. The very top picture is of a tree flowering at Palermo last year. The middle picture is of the tree lit up at Christmas. The lower picture is from the Palermo landscaping plan. Here is some information about it: "This semi-evergreen, thornless, Palo Verde hybrid exhibits qualities found in Foothill, Blue and Mexican Palo Verde, provides ample shade, distinctive rich green trunks and branches that, similar to the Palo Brea, remain smooth as they mature, and abundant brilliant yellow flowers that appear in spring and intermittently during the summer months. In the late 1970s Mark Dimmitt with the Arizona Sonora Desert Museum began noticing Blue Palo Verdes that exhibited characteristics suggesting they were hybrids of other Palo Verde species. He collected and planted seeds from the assorted trees he had observed and began evaluating them. By 1981 he had identified a thornless seedling as clearly superior to the others collected. Careful evaluation of the genetic composition of this hybrid, named 'Desert Museum,' revealed it to be a complex hybrid having genetic characteristics from Mexican, Blue and Foothill Palo Verde. Dimmitt suspects that 'Desert Museum' gets it vigorous growth, sturdy, upright branching habit and bright flowers from P. aculeate, and its small delicate leaves from the Cercidium species. Trees have tolerated temperatures of 15 degrees without damage . The most remarkable and unique feature of this hybrid is the absence of thorns. Flowers are slightly larger than those of P. aculeata and other Cercidiums and trees have been observed to flower abundantly as early as mid-March with intense, full bloom lasting into late spring and early summer. Intermittent flowering can continue into the mid to late fall. Pruning and staking is best done during the growing season when the trees limbs are more flexible. The v-shapes branching, thornless growth and ample shade make Desert Museum a pedestrian friendly desert adapted tree that could be used in a wide array of landscape applications. Foster the development of a more dispersed root system and reduce the risk of wind throw by arranging irrigation emitters at varying distances from the trunk to encourage roots to "seek out" water and nutrients. Prune as needed to reinforce the structure and form of the tree. Periodic thinning is the most desirable method of pruning. Avoid hedging or heading back desert species, as this will only stimulate excessive branching. Do not remove more than 30% of the canopy during the summer as this can lead to sunburn injuries that can later be invaded by wood boring insects." Miss Penny Lane says: For the last several years she's awaited the yellow flowers every spring and celebrates them by buying a bag of lemons for an evening martini.