Scientific: Fraxinus uhdei
Common: Shamel ash or evergreen ash
Origin: Mountain canyons of south-central Mexico just north of Mexico City into central America.
Pronounciation: FRAX-i-nus UH-dee-ii
Sunset 9, 12-24
USDA 9 (needs cold protection when young)-11
Landscape Use: Large to massive evergreen to semi-evergreen shade tree, parks, commercial, large areas and mesic design themes. Not for small residential sites.
Form & Character: Briefly deciduous to mostly evergreen tree (depending on winter cold in Phoenix), upright and rounded, potentially massive and stout.
Growth Habit: Woody, mostly evergreen perennial tree, vigorous to 80-feet tall with a 60-feet spread.
Foliage/Texture: Large pinnately-compound green leaves, mostly 7 sometimes 9 leaflets per leaf. Leaflets are ovate to lanceolate with serrate, sometimes revolute margins, trunk and branches smooth when young becoming slightly rough with age; medium to medium coarse texture.
Flowers & Fruits: Dioecious, flowers inconspicuous born on separate trees in mid winter just before or at leaf emergence; fruit a winged achene, inconspicuous.
Seasonal Color: Marginal and inconsistent (from year to year depending on the weather) golden yellow early winter color.
Temperature: Freezing temperatures will defoliate most trees and can kill young twigs, injured trees recover quickly.
Light: Full sun
Watering: Apply regular water throughout the year.
Pruning: Elevate canopy base, not as susceptible to trunk scald like other Phoenix ash trees mainly due to greater heat tolerance and a wider canopy spread.
Propagation: Cutting or grafting most common.
Disease and Pests: None, appears to be mostly resistant to ash decline.
Additional comments: Lateral buttress roots of mature specimens of Shamel ash can heave concrete. Large canopies can shade out Bermuda turf grass, Ergo, use Shamel ash as a lawn tree and/or around concrete walks and drives with great discretion because of its heavy surface roots and dense canopy shade. The cultivar 'Majestic' is both relatively common and popular.