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White Ash

Fraxinus americana

Leaves: Deciduous. Pinnately compound leaves 8-15” long, 5-9 leaflets, usually 7. Each leaflet is 2-6” long, 1-3” wide, ovate and pointed at the end. Dark green color with a lighter underneath. Dark purple to yellow fall color.

Bark/Twigs: Ash gray to gray-brown colored bark. Furrowed into close diamond shaped areas. Bark very distinctively cross-hatched.

 Flowers/Fruit: Inconspicuous flowers. Dioecious- species have both male and female trees. Female trees produce 1-2” long, ¼” wide seeds which look like a canoe paddle.

Mature size and shape: Large. 50-80’h x 50’w. Younger trees are pyramidal to upright oval. As it ages the tree develops a rather open rounded crown.

General information/special features: Plant in full sun. Grows best in deep, moist, well-drained soil, but can withstand soils that are not too dry and rocky.

Landscape use and Maintenance: Good shade tree. Medium growing rate. Average maintenance. Easily transplanted. Buy male varieties to avoid messy seeds.

USDA Hardiness Zone: 4-9

Family/Origin: Oleaceae – Olive. A large tree native to moist sites in most of the eastern U.S.

Campus use: Somewhat common. Can be found west of Building 379 along Mario Capecchi Dr.

 

Velvet Ash (Dixie White Ash)

Fraxinus velutina

Leaves: Deciduous.  Pinnately compound leaves 3-6” long. 3-9 leaflets (typically 5) each 1-2” long, ovate with pointed tips. Soft velvety undersides as its name suggests. Bright medium to dark green summer color with bright yellow fall color.

Bark/Twigs: Ash gray to gray-brown colored furrowed bark. Distictive cross-hatch pattern similar to the green ash.

Flowers/Fruit: Inconspicuous flowers followed by the production of showy, persistent fruits. Dioecious- species have both male and female trees. Female trees produce 1” long, ¼” wide seeds which look like a canoe paddle.

Mature size and shape: Medium. 30-50’h x 45’w. Slightly pyramidal when young, developing into an upright-spreading habit. Crown is extremely irregular in shape and roundish.

General information/special features: Plant in full sun. Grows in almost all soil types. Tolerates heat, drought, and alkaline soil.

Landscape use and Maintenance: Drought tolerant shade tree for warmer dry climates. Fast growing rate. Average maintenance. Transplants readily. Buy male varieties to avoid messy seeds. Sometimes called a ‘Modesto’ ash since that is the most common cultivar. Also called the “Dixie White Ash” named for southern Utah.

USDA Hardiness Zone: 6-9

Family/Origin: Oleaceae – Olive. Native to the southwestern U.S. and northern Mexico including the canyons of extreme southwestern Utah.

Campus use: Rare. Only specimen. Can be found west of George Thomas (Bld 5).

 

Flowering Ash (Manna Ash)

Fraxinus ornus

Leaves: Deciduous. Compound leaf is 5-8” long, usually with 7 leaflets (5-9), each leaflet 2-4” long, ¾-1¾” wide, oval shaped with a point at the end. Irregularly serrate leaf edge and dull dark green color. The autumn color is variable, yellow to purplish.

Bark/Twigs: Bark is smooth and gray, even on older trees.

Flowers/Fruit: Showy, off-white, fragrant flowers. Borne in 5” long clusters (panicles) in May.

Mature size and shape: Large. 40-50’h. Rounded, spreading form.

General information/special features: Plant in full sun. A sugary extract from the sap was compared in late mediaeval times with the biblical manna, giving rise to the English name of the tree. In fact, the sugar mannose and the sugar alcohol mannitol both derive their name from the extract.

Landscape use and Maintenance: Ornamental shade tree. Average growing rate. Average maintenance.

USDA Hardiness Zone: 6-9

Family/Origin: Oleaceae – Olive. Native to southeastern Europe and western Asia.

Campus use: Extremely uncommon. Can be found east of the Officer’s Club (Bld 649).

 

 

Green Ash

Fraxinus pennsylvanica

Leaves: Deciduous.  Pinnately compound leaves 10-12” long. 7-9 leaflets each 2-5” long, 1-2” wide, ovate with pointed tips. Bright medium to dark green summer color. Yellow fall color.

Bark/Twigs: Ash gray to gray-brown colored bark. Furrowed into close diamond shaped areas.  Flowers/Fruit: Inconspicuous flowers. Dioecious- species have both male and female trees. Female trees produce 1-2” long, ¼” wide seeds which look like a canoe paddle.

Mature size and shape: Large. 50-60’h x 25-30’w. Slightly pyramidal when young, developing into an upright-spreading habit. Crown is extremely irregular in shape.

General information/special features: Plant in full sun. Grows in almost all soil types. Tolerates salt, drought, alkaline soil, and wind.

Landscape use and Maintenance: Good shade tree. Grows anywhere, but needs a very large space. Fast growing rate. Average maintenance. Transplants readily. Buy male varieties to avoid messy seeds.

USDA Hardiness Zone: 3-9

Family/Origin: Oleaceae – Olive. Native from the Great Plains east, including southern Canada.

Campus use: Very common. Can be found in President's Circle and west of George Thomas (Bld 5).

German Ash

Fraxinus holotricha

Leaves: Deciduous.  Pinnately compound leaves 7-9” long. 7-9 leaflets each 1 ½ -2 ½ ” long, lance-shaped with pointed tips. The leaf is dark green, underneath grey and hairy and turns golden-yellow in fall.

Bark/Twigs: Ash gray to gray-brown colored bark. Furrowed into close diamond shaped areas.

Flowers/Fruit: Inconspicuous flowers. Dioecious- species have both male and female trees. Female trees produce ½ -1 ½ ” long, ¼” wide seeds which look like a canoe paddle.

Mature size and shape: Medium to large. 30-45’h x 25-30’w. Pyramidal when young, developing into a spreading pyramidal habit.

General information/special features: Plant in full sun. Tolerant of pollution. Does not tolerate compacted soil.

Landscape use and Maintenance: Shade tree. Good in industrial areas. Fast growing rate. Average maintenance. Used as a street tree in Europe. The common cultivar is ‘Moraine’ and produces very little flowers and fruit.

USDA Hardiness Zone: 6-8

Family/Origin: Oleaceae – Olive. Native to south east Europe.

Campus use: Rare. Only specimen. The tree south of the Park Building (Bld 1) is on the Utah Big Tree Registry.