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Weed Identification

green ash



Scientific Name

Fraxinus pennsylvanica

Synonyms (former Scientific Names):

Fraxinus pennsylvanica var. lanceolata
Fraxinus campestris
Fraxinus lanceolata
Fraxinus pennsylvanica var. subintegerrima
Fraxinus pennsylvanica var. integerrima
Fraxinus smallii
Fraxinus darlingtonii
Fraxinus pennsylvanica var. austinii


Fruits are straw-colored, one-seeded, winged (samaras), 1 to 2 1/2 inches long, borne in dense branching clusters; flowers are inconspicuous, without petals, borne in dense clusters (panicles) near the ends of the twigs, male and female flowers on separate trees; leaves are opposite, pinnately compound, 4 to 6 inches long, 7 to 9 leaflets, narrowly elliptical, long-pointed, entire, bright green above, paler below; stem straight, bark thin with network of interlacing ridges, brown to dark gray, twigs smooth; roots are shallow, wide-spreading

Identifying Characteristics

Fraxinus pennsylvanica Marsh., green ash, is a deciduous, medium-sized tree with an open, irregular crown reaching about 50 feet in height. Native to eastern North America and is fairly common west to Wyoming and Colorado along plains watercourses at elevations below 6,000 feet. The tree is fast growing on moist bottomlands, and is extremely hardy to climatic extremes once established.

Where Found

Green ash is widely adapted to soils, moisture conditions and pH found east of the Rocky Mountains. The species will tolerate seasonal flooding, but is intolerant of shading from surrounding trees. Green ash is a fairly early successional tree on most sites. Green ash is distributed throughout the east and midwest of the United States.

Growth Habit

woody bush or tree

Thorns or Spines

not present

Approximate Flower Diameter


Dominant Flower Color


Flower Symmetry

bilateral symmetry

Leaf Hairs

no hairs

Leaf Shape


Leaf Arrangement


Leaf Margin


Leaf Structure


Leaf Stalk

longer than leaf

Stem Hairs

no hairs

Stem Cross Section

round or oval

Milky Sap

not present

Life Cycle



not present

Plant Type