horsechestnut (Aesculus hippocastanum)

Third place champion horsechestnut in Denver at University of Denver.

Species info:

Leaves: Opposite, palmately compound with usually 7 obovate, serrated leaflets (each 4–6 inches long). Leaflets are elliptic-oblong and pointed at the tip.

Leaflets: 5–7 per leaf, arranged in a fan-like pattern.

Leaf Surface: Dark green above, paler beneath; large and coarse-textured; turn yellow-brown in fall.

Bark: Light to dark brownish gray, becoming scaly and rough with irregular ridges on older trees.

Flowers: Creamy white in large, showy, upright clusters (5–8 inches long), aging to dull red; bloom in spring.

Fruit: Rich brown, shiny nuts (conkers) enclosed in a leathery, spiny husk; 1–3 seeds per husk. Nuts are moderately toxic if eaten.

Botanical: Ulmus parvifolia

Family: Ulmaceae

Mature Height: 40–60 feet

Canopy Spread: 25–50 feet

Foliage Type: Deciduous

Tree Shape: Rounded, stately form with dense canopy

Growth Rate: Medium (approximately 18 inches per year when young, slower with age)

Fall Color: Yellow-brown

Water Use: Moderate; prefers moist, well-drained soils but tolerates drought once established

Hardiness: Zones 3–7

Soil Preference: Prefers deep, fertile, moist, well-drained soils; tolerates a range of soil types

Wildlife Value: Limited; seeds are not palatable to most wildlife due to toxicity

Pests/Pathogens: Prone to leaf blotch and leaf scorch, particularly during hot or dry periods; may appear unsightly in midsummer

Planting Recommendations: Recommended for most sites along the Front Range; poor salt tolerance

Information Sources:

• Front Range Tree Recommendation List

• Michael Dirr, Manual of Woody Landscape Plants (University of Georgia, 1990)

• Michael Kuhns, Trees of Utah and the Intermountain West (Utah State University Press, 1998)