Acer negundo.  Synonym: Negundo aceroides.  (Box Elder)
Sapindaceae (Soapberry Family) Synonym: Aceraceae (Maple Family)

Box Elder is common along lower elevation streams, sometimes growing to 35 feet tall and 3 feet in diameter. Often there are many small branches at the base and along the knobby, distorted trunk.  Box Elder is fast growing and its wood soft; branches often split from wind and snow.

The genus and species were first named Acer negundo by Linnaeus in 1753. "Acer" is derived from the Latin for "sharp" as in "acrid" or "acerbic". Romans apparently used some hard Maple wood for sharp spears. The Maple Family was called Aceraceae. "Negundo" is Sanskrit and of unknown meaning.

Acer negundo.  Synonym: Negundo aceroides.  (Box Elder)
Sapindaceae (Soapberry Family) Synonym: Aceraceae (Maple Family)

Semi-desert, foothills, montane. Washes, streamsides. Spring.
Top two pictures at left: Animas River Trail, May 15, 2007.
Dolores River Trail, April 28, 2008.
Durango, July 20, 2013.  

Box Elder is dioecious , i.e., male flowers are on one tree and female flowers are on another.  In late spring the winged seeds (samaras) develop on the trees bearing female flowers; the samaras do not drop from the tree until they are quite dry and uniformly light brown. When the seeds do drop, they rotate like helicopter blades and are a great toy for kids.  

Box Elder leaves, especially the young spring leaves, are very similar in shape and color to Poison Ivy leaves.

Box Elder branch tips and young vigorous trunks range from tan to light yellow-green.

Acer negundo.  Synonym: Negundo aceroides.  (Box Elder)
Sapindaceae (Soapberry Family) Synonym: Aceraceae (Maple Family)

Semi-deserts, foothills, montane. Washes, streamsides. Spring.
Grandstaff Canyon, Utah, April 19, 2004.

Handsome spring green on straight-growing Box Elders fills the eyes in Canyon Country.

Acer negundo.  Synonym: Negundo aceroides.  (Box Elder)
Sapindaceae (Soapberry Family) Synonym: Aceraceae (Maple Family)

Semi-deserts, foothills, montane. Washes, streamsides. Spring.
Highway 145 north of Dolores, September 30, 2000.

Fall leaf color is most often various intensities of yellow but can also range through reds and oranges.

Acer negundo.  Synonym: Negundo aceroides.  (Box Elder)
Sapindaceae (Soapberry Family) Synonym: Aceraceae (Maple Family)

Semi-deserts, foothills, montane. Washes, streamsides. Spring.
Lower Calf Creek Trail, Escalante/Grand Staircase National Monument, October 23, 2007.

Range map © John Kartesz,
Floristic Synthesis of North America

State Color Key

Species present in state and native
Species present in state and exotic
Species not present in state

County Color Key

Species present and not rare
Species present and rare
Species extirpated (historic)
Species extinct
Species noxious
Species exotic and present
Native species, but adventive in state
Eradicated
Questionable presence

Range map for Acer negundo