Palo Colorado
Coulteria platyloba
Family: Fabaceae
OTHER NAMES
Curly Paela
CHARACTERISTICS
This is a mostly evergreen tree (in protected locations) reaching up to 30’ tall, but in cultivation rarely over 20. Yellow flowers appear spring into late summer followed by legume pods. Rare in the trade.
LANDSCAPE USE
Specimen tree.
GROWING CONDITIONS
AN EXPLANAITION OF TERMS USED
SUN full to part sun
WATER moderate
SOIL not picky, but well-drained
HARDINESS can tolerate light frosts when established but best planted in a protected microclimate
BASIN high zone
CONTAINER does moderately well in containers but will not attain full size
NUTRITION low
MAINTENANCE very little
Photo of Coulteria platyloba at University of Arizona arboretum
ECOLOGY
Bees especially love the flowers though they are visited by many nectar-seeking insects.
ETHNOBOTANY
In the wild, larger trees are difficult to find because of over-harvesting. The hard wood is valued for fenceposts, which reportedly last a century in the ground.
NATURAL DISTRIBUTION
Native from Chihuahua and Sonora and south at least to the state of Colima, Mexico.
TAXONOMY AND NAME
This plant is in the Fabaceae, the legume family. The genus Coulteria has 18 species.
This plant was formerly known as Caesalpinia pumila.
The genus Coulteria was named for the Irish botanist Thomas Coulter (1793–1846) who collected in central Mexico (1825–1834) and was curator of the herbarium at Trinity College, Dublin, Ireland. Platyloba is from the Greek πλατύς (wide, flat, wide, large) characteristic of the leaves.
Coulteria platyloba on iNaturalist
Coulteria platyloba at the UA Campus Arboretum where you can go see some plants
Trees are almost always multi-trunked though they are very upright-growing. Photo by J. Fernando Pío León, iNaturalist
Legume pods follow the flowers. Photo by elsamariaguadalupeibarracarranza on iNaturalist
Flowers occur in spring, into summer. Photo by Carlos Domínguez-Rodríguez, iNaturalist