Cercidium Desert Museum’
Cercidium hybrid ‘Desert Museum’ 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.
Cercidium heralds the arrival of the desert spring (and in some years 100 degree temperatures) as brilliantly and conspicuously as the blooming of the Palo Verdes. With a succession that includes Blue (Cercidium floridum), Foothill, Mexican and Sonoran, Palo Verdes color the desert a brilliant yellow from spring to early summer. Other than Mexican Palo Verde (Parkinsonia aculeata) all the Palo Verdes are popular and widely used landscape trees. All these species are so closely related botanically that hybridization between species is quite common in native and nursery environments. In the past this hybridization went largely unnoticed or was mistaken for genetic seed variation within a single species. The potential for hybrids to offer advantages like increased vigor, greater cold hardiness, enhanced flowering and absence of thorns eventually brought them to the attention of horticultural professionals.
Cercidium 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. Always use clean, sharp tools that are cleaned regularly in a 10% solution of bleach. For detailed Cercidium pruning guide see Pruning Desert Trees.