Cronquist System

Order:

Sapindales

Family:

Aceraceae

Genus:

Acer

APG System

Order:

Sapindales

Family:

Sapindaceae

Genus:

Acer

Description

Description:

Acer negundo is a deciduous tree with a rounded crown. It grows as hig as 60 ft. , but 30 to 40 feet is more typical for an open grown tree, and 15 to 20 feet for one in the shade.

Branching:

Opposite

Leaves:

Pinnately compound leaves. There may be as few as three leaflets, but five or seven leaflets per leaf is more common.

Flowers:

Box elder flowers grow in panicles or racemes. They are pink in color. Flowering is often in March or April, sometimes as late as May.

Fruit:

The seeds are in doubles, hanging by a stem from the branch. Each seed has a wing.

Plant Relationships

Related California Species:

Acer circinatum
Acer macrophyllum

Vine maple
Bigleaf maple

Related Exotic Species:

Acer rubrum
Acer palmatum
Acer platanoides
Acer saccharum
Acer saccharinum

Red maple
Japanese maple
Norway maple
Sugar maple
Silver maple

Growing Conditions

Natural Range and Habitat:

Acer negundo is found throughout the United States and much of Canada, from coast to coast. It is more common east of the Missouri and east of the Mississippi. The local variety, Acer negundo var. californicum, is endemic to California.
Box elder is found in a wide variety of habitats, from sea level to 6000 ft. It is most common in or near riparian zones or moist meadows.

Sun and Exposure:

Box elder is shade tolerant, and is commonly found in riparian woodlands, however, shade grown plants have poor form, and have small, weak branches. The plant requires full sun to achieve a good form.
It is more common inland than along the coast, and can withstand heat far better than Acer macrophyllum.

Soil and Moisture Requirements:

Acer negundo grows where there is a stable water source during the summer. This can be a riparian zone, an elevated water table or a spring.

Horticulture and Restoration

Wildlife Habitat:

Restoration:

Acer negundo var. californicum is most commonly used in riparian restoration projects, often in the shade.

Uses in Landscaping:

When grown in the full sun in good conditions, it has the typical, sturdy maple tree appearance and can grow fairly large. If grown in the shade, as in a riparian zone, it is much reduced in size, with many small branches.

Horticultural Comments:

Sunset zones 1-10 and 12-24.
USDA zones 4-10
They are easy to grow from seed. The seed must be used fresh, because it dries out easily. Stratification is required for germination.
These trees are known for being infested by insects, but I have never seen it happen. Be aware of the potential for an insect problem, but don't let this be a factor in selecting or rejecting this tree.