Utah Ash

Year-round

Utah ash (Fraxinus anomala) is a slow growing, deep rooted small tree built for hot dry canyons and washes, and it needs very little care once it is established in your yard.

• This tree evolved in dry rocky canyons and washes with as little as about 5 to 19 inches of rain a year, so once roots are established it needs very little supplemental water.
• Give it full sun and well drained soil. It tolerates sandy, gravelly, and even clay soils, which is unusual for a desert tree.
• Growth is slow. Expect a compact, rounded tree around 15 to 20 feet tall over time, good for a smaller yard.
• Unlike most ash trees, this species usually grows simple, single leaflets instead of the typical compound ash leaf. That is where the names Utah ash and singleleaf ash come from.
• We could not confirm this tree's toxicity to pets. It has no entry on the ASPCA's toxic and non toxic plant list, so its status is undetermined rather than confirmed one way or the other. Keep an eye on pets around any tree you are unsure about.
• Prune only while the tree is dormant in late fall or winter, and trim off any root suckers at the base to keep a single clean trunk.

Fall

Fall is this tree's best season to look at. The leaves turn a bright, clear yellow before dropping, and it is also the right time to start easing off on water.

• Foliage turns a bright, clear yellow in fall, one of this tree's best ornamental features.
• Cut back on watering as temperatures drop and the tree heads into dormancy.
• Rake and clear fallen leaves from around the base to keep the area tidy and reduce spots where pests can hide over winter.
• Late fall, once the tree is bare, is a good time to start structural pruning since you can finally see the branch shape clearly.
• This is a slow grower, so do not expect dramatic size change year to year. Fall color is the main show.

Raking fallen leaves and starting cleanup pruning once the tree is bare keeps a front yard planting looking tidy for HOA-conscious curb appeal.

Winter

This is a fully deciduous tree, so expect bare branches all winter. It needs almost no water, and this is the best time to prune.

• Utah ash drops all its leaves and goes fully dormant in winter. Bare branches are normal, not a problem.
• Established trees need little to no supplemental water during winter in most climates.
• Dormant season is the best time to do any shaping or dead wood pruning, since the branch structure is easy to see without leaves in the way.
• This species naturally grows at elevations up to about 11,000 feet in canyon country, so mature trees handle cold well. A young, newly planted tree can still use basic trunk protection if a hard freeze is expected.

A clean, intentionally shaped winter silhouette from dormant season pruning reads as cared for rather than neglected, good for HOA-conscious curb appeal.

Spring

Spring is leaf out and bloom time. New foliage appears along with small, easy to miss flowers, and root suckers start showing up at the base.

• New leaves emerge in spring. Watch for the tree's simple, single leaflet look, its most distinctive trait among ash trees.
• Flowers are small, greenish, and wind pollinated, with no petals or scent, so do not expect a showy bloom.
• If your tree is young or was recently planted, give it a deep, slow soak every few weeks through spring to help the roots settle in. Established trees can go much longer between waterings.
• Check the base of the trunk for root suckers and clip them off while they are small, before they turn into a thicket of extra stems.
• Once leaves are fully out, take a look for any branches that did not survive winter and prune those out.

Clearing root suckers and any winter killed branches keeps a front yard tree looking tidy and intentional, good for HOA-conscious curb appeal.

Summer

Summer heat and dry spells are exactly what this tree evolved for, so summer care is mostly about resisting the urge to overwater.

• This species is documented tolerating as little as about 5 inches of annual rainfall in parts of its native range, so it is built to handle a hot, dry summer without regular irrigation.
• Once established, skip a regular watering schedule. An occasional deep soak during a long heat wave is enough, especially for a tree still under 3 to 5 years old.
• Full sun all summer is normal and expected for this canyon and wash growing species.
• Watch newly planted or younger trees for leaf scorch or early leaf drop during extreme heat spikes. That is a sign they need a deeper soak.
• Palm Springs area yards sit lower and hotter than the rocky canyons this tree usually grows in, so a young tree here may appreciate a little afternoon shade or extra water until its roots go deep.