Green ash

 Physical Information

Size and Form.  Green ash is a native , deciduous tree with a large trunk and high branches. This diecious tree grows 12-16 meters high with a diameter of30-60cm.The trunk can sometimes be poorly formed and supports a broad irregular crown The tree can sometimes be crooked with stout upright branches. Green ash has an extensive, moderately shallow root system, which contributes to a high degree of windfirmness. The roots often appear as a superficial fibrous root system.

 

 

 

 

Bark.  The bark is thick with many irregular, vertical, shallow furrows and interlacing ridges, and may appear scaly. It is colored brown or dark-gray to brown and the wood is heavy, hard, strong and yellowish with wide, white sapwood.

 

 

 

Leaves.  These are oppositely arranged and pinnately-compound. They are 25-30 cm long with leaflets 7-13 cm long and 2.5-4.5 cm wide. They can be oblong-lanceolate to oval shaped and slightly or completely serrate with petioles which are stout, glabrous or pubescent. The leaves are yellowish-green on both sides.

 

 

 

Twigs. Twigs are usually stout or densely pubescent, with the pubescence lasting 1-3 years.They are reddish-brown to ashy gray and turn reddish in early spring. Leaf scars are sometimes straight across at the top with the bundle scars forming a U-shaped or V-shaped line. Epidermis of older twigs does not peel or flake and leaf scars are sometimes straight across.

Winterbuds

The terminal bud is round and small with rounded bud scales.There are usually three pairs which are rusty brown in color.The upper pair of lateral buds are at the same level as the terminal bud.

Flowers Appear around May before or with the leaves. They are borne in compact panicles on the shoots of the previous season. The calyx is cup-shaped and four toothed with no corolla. The male flowers have two stamens while the female flowers have two-celled ovary. The trees are dioecious and are wind pollinated. The unisexual flowers are borne over the entire outer part of the live crown. The staminate flowers are dense panicles which are green with reddish anthers; pistillate flowers are greenish-yellow in short panicles.

Fruit.   Appear in September and persist until winter. They are 2.5-5 cm long and grow in open, paniculate clusters. They are winged, single-seeded samara and large seed crops are produced every year.The seed cavity is narrow and cylindrical.

Wood.   This is heavy, hard and strong wood which is coarse grained. It is light brown with thick yellow-streaked sapwood having porous rings. It has a high specific gravity and a low moisture content which make it a valued species for solid wood products.

  Horticultural Information

Green ash is exceedingly hardy to climatic extremes and will persists even on dry sterile soil. In a naturally moist environment such as along a stream-bank it becomes rapidly established. It occurs in a wide variety of soils and thrives best on deep, permeable, well-drained loams. Green ash can grow on medium to coarse-textured upland sands and loams with good moisture relations. It tolerates moderately strong acid (pH 4.0) to moderately basic soils. Green ash can persist on very dry soil and is therefore often used as shelter-beds. Under forest competition, green ash is intolerant to moderately tolerant of shade. Green ash is a fast growing species and is moderately long-lived.

  Distribution

Green ash is the most widely distributed of the American ashes. It is common, especially throughout the Mid-west and its range extends from Cape Breton Island and Nova Scotia to southeastern Alberta and Montana, and southward to central Texas and northern Florida. Fraxinus pennslyvanica var. subintegerrima (lanceolata) is found mainly in the northern Great Plains region.The tree can be found along roadside ditches, highway median strips and old fields. It is common to occasional throughout the state of Michigan and can be found in characteristic sites that are poorly drained or flooded during the spring. Even though Green ash is a flood tolerant tree it is not found  in areas of continuing high water tables such as in swamps. Green ash grows in a subhumid to humid climate with an average annual precipitation of 38-155cm and an average length frost free season from 120-280 days.

  Economic uses

Given its high specific gravity and low moisture content Green ash is used for solid wood products as well as for pulp and paper requiring hardwood fibers. Crating, boxing, handle stock and rough lumber can be obtained from green ash.

  Other uses

Green ash rates as having moderate potential for erosion control and for long term revegetation. Green ash woodlands are considered to be important habitats for a number of wildlife species. They provide year-round habitat for deer and contribute both browse and shelter. Other mammal species also found in green ash woodlands include: coyotes, rabbits, raccoons and several other species of small mammals.

Although green ash is of low palatability it is often browsed by deer and certain other species. Its nutritional value is low and its protein content is poor even though it has a fair energy value.

This tree has been used extensively in wind break plantings due to its survival and adaptability. Its moderate drought resistance makes it an ideal windbreaking plant in the central Great plains. Green ash is cultivated as an ornamental tree and is often planted for its shade and landscape beautification in parks and recreational sites.

  Medicinal uses

  References  

Bellah, R. Glenn; Hulbert, Lloyd C. 1974. Forest Succession on The Republican River Floodplain in Clay County, Kansas. Southwestern     Naturalist. 19(2): 155-166. (241).
Cram, W. H. ;Lindquist, C. H. 1982. Germination of Green Ash is Related to Seed Moisture Content. Forest Science. 28(4) : 809-812.
Dittberner, Philip L. ; Olson, Michael R. 1983. The Plant Information Network (PIN) Data base: Colorado: U.S. Department of the Interior, Fish and Wildlife Services. 786p. (806).
Fitzgerald, Charles et al. 1975. Characteristics and Growth of Natural Green Ash Stands. Journal of Forestry. 73: 486-488. (5122).

Websites:

www.http/plants.usda.gov/plants
www.mpelectric.com/treebook

This page written by E.Stephan Persad for Bio 141, Botany, Fall 98.