Green Ash, one of the most common and rapidly growing woodland trees in Ohio, is also a popular shade tree for urban areas, well-known for its adaptability to almost any site.
One of the first trees to change color and drop its leaves in autumn, it is native to eastern and central North America, where it is found primarily in floodplains, cut-over forests, and abandoned fields.
It grows to about 60 feet tall by 40 feet wide when found in the open, with a medium to rapid growth rate. Its shape is upright oval when young, becoming upright spreading to upright rounded with maturity. In addition, its lower branches become both pendulous and upswept with age. As a member of the Olive Family, Green Ash is related to the other Ashes, as well as the Fringetrees, Forsythias, Privets, and Lilacs.
Historically, Green Ash was once considered a variety of Red Ash. The old Red Ash was distinguished by the ruddy fuzziness on its leaflet undersides and stems, and for the tendency of its fall foliage to have traces of a burgandy or red color. The old Green Ash had leaf and stem features that were smooth. Now, these two types of Ash are considered as one, and are collectively called Green Ash.
Planting Requirements - Green Ash is very adaptable to a wide range of soil types (organic, clay, sandy, or rocky), soil pHs (acidic, neutral, or alkaline), and moisture levels (wet, moist, or dry). It is noted for being extremely tolerant to many types of environmental stresses (summer heat, reflected light, sweeping winds, drought, flooding, poor soils, compacted soils, high pH soils, winter salt spray, winter salt deposition, and air pollution). It grows in full sun to partial sun, and is found in zones 3 to 9.
Potential Problems - Among the common ash trees, Green Ash is generally the most healthy. This is why it is overplanted as a street tree and shade tree in urban areas (only the seedless male cultivars are sold as landscape trees today). However, borers and scales are still occasional pests, while leaf anthracnose and trunk canker are occasional diseases. In addition, seed litter from female trees, surface roots (with age in compacted or shallow soils), and storm damage at maturity due to easily splittable wood with weak crotch angles are potential liabilities, primarily in urban areas.
Emerald Ash Borer(Agrilus planipennis), is a destructive exotic pest from Asia. This metallic wood-boring beetle attacks all of Ohio's native ash species, and has no known significant natural enemies in this country. EAB has been discovered infesting ash trees in Michigan, Ohio, Indiana, and Illinois. The first Ohio discovery was in Lucas County in February of 2003