Black Ash (Nigra)

The Black Ash (Nigra) is generally described as a perennial tree. This is native to the U.S. (United States) has its most active growth period in the spring and summer . The greatest bloom is usually observed in the early spring, with fruit and seed production starting in the summer and continuing until summer. Leaves are not retained year to year. The Black Ash (Nigra) has a moderate life span relative to most other plant species and a moderate growth rate. At maturity, the typical Black Ash (Nigra) will reach up to 80 feet high, with a maximum height at 20 years of 20 feet.

The Black Ash (Nigra) is easily found in nurseries, garden stores and other plant dealers and distributors. It can be propagated by bare root, container, seed. It has a slow ability to spread through seed production and the seedlings have low vigor. Note that cold stratification is not required for seed germination and the plant cannot survive exposure to temperatures below -38°F. has low tolerance to drought and restricted water conditions.

Uses of : Landscaping, Medicinal, Culinary, etc.

Cultural: The primary use of black ash is as a source of basket-making materials, particularly for Native Americans.

Timber: It has some use as flooring, as which it performs admirably.

Wildlife: Young trees are preferred as deer browse.

General Characteristics

Black ash, is a native, deciduous tree which has important cultural significance to Native Americans. Alternative common names are descriptive of the preferred habitat and the primary use of the species. Black ash is a small to medium sized tree with opposite branching and compound leaves. Leaflets number 7-11 (typically more than green ash) and are green and smooth on both sides. The terminal leaflet has a short stalk, but the other leaflets are attached directly to the leaf stalk (petiole). The fruit is a samara with a broader wing than that of green ash. The bark is pale gray and flaky, and the crushed foliage smells like elderberry. The first key to identifying black ash is its location on poorly drained sites. It is slower growing (1.5-2.5 ft/yr) than associated trees such as red maple.

Required Growing Conditions

Black ash grows on sites and soils with generally poor drainage, including peat, fine sands, and loams in bogs, streambanks and other low spots. It can tolerate a wide range of soil pH. The range of the species extends from the Mason-Dixon Line north to western Ontario and east to the Maritimes. Black ash is shade intolerant and requires some soil disturbance to invade a site naturally.

Cultivation and Care

The seed of black ash seems to have both seed coat dormancy and chemical dormancy, with immature embryos thrown in for goods measure. Thus getting the seed to germinate in the nursery can be a challenge. Apparently planting the seed very soon after harvest is key to germination. Otherwise a series of natural or artificial cold and warm stratifications will likely be necessary to achieve germination.Direct planting of seeds is likely to be sparsely successful.Seedlings must be planted in appropriate soil and site conditions. The species often grows as an understory tree or partly suppressed by other species.

General Upkeep and Control

Little is known about managing young stands of black ash. Keeping competing vegetation from totally shading the ash, and protection from heavy deer concentrations are likely strategies. Livestock of all classes must be excluded from the site.

Cultivars, Improved, and Selected Materials (and area of origin) While none currently exist, the interest in the species will result in the culture of known source materials.

Plant Basics
Growth Rate Moderate
General Type Tree
Growth Period Spring, Summer
Growth Duration Perennial
Lifespan Moderate
Plant Nativity Native to U.S.
Commercial Availability Routinely Available
Physical Characteristics
Bloom Period Early Spring
Displays Fall Colors No
Shape/Growth Form Single Stem
Drought Tolerance Low
Shade Tolerance Intolerant
Height When Mature 80
Vegetative Spread None
Flower Color White
Flower Conspicuousness No
Fruit/Seed Abundance Low
Fruit/Seed Seasonality Summer Summer
Seed Spread Rate Slow
Gardening Characteristics
Propagations (Ways to Grow) Bare Root, Container, Seed
Moisture Requirements High
Cold Stratification Required Yes
Minimum Temperature -38
Soil Depth for Roots 40
Toxic to Nearby Plants No
Toxic to Livestock No
After-Harvest Resprout Ability Yes
Responds to Coppicing No
Growth Requirements
pH Range 4.2–6 pH
Precipitation Range 20–20 inches/yr
Planting Density 300–800 indiv./acre
Soil Textures Coarse, Medium
Soil Depth for Roots 40
Minimum Frost-Free Days 90 day(s)
Salinity Tolerance None
Sustainability & Use
Leaf Retention No
Palatability Low
Fire Resistant No

Source: USDA, NRCS, PLANTS Database,
National Plant Data Center, Baton Rouge, LA 70874-4490 USA