he leaves of the Blue Ash are dark green and turn pale yellow in the fall. The bark of the tree is gray, platelike, and sometimes shaggy. The Blue Ash is known for its tolerance of drought and lime, making it a potentially great choice for street landscaping.
The Blue Ash, scientifically known as Fraxinus quadrangulata, is native to the American Midwest, including regions such as Kentucky, Tennessee, and parts of Alabama. It can also be found in Southern Ontario and some sections of the Appalachian Mountains. This species thrives on calcareous substrates, particularly limestone, and can be found growing on limestone slopes and in moist valley soils at elevations ranging from 120 to 600 meters.
One interesting feature of the Blue Ash is the blue dye that can be obtained from its inner bark. This dye has historical uses, as European colonists and American pioneers extracted it to color yarn for textile production, sewing, crocheting, knitting, weaving, and embroidery. Beyond its dye properties, the wood of the Blue Ash is extremely versatile and is used to make various products, including flooring, baseball bats, furniture, tool handles, crates, and barrels.
The city of Blue Ash, Ohio, derived its name from the abundance of blue ash trees in the area. These trees were used to build many of the community's earliest buildings, showcasing the significance of this species in the region's history.
Importantly, the Blue Ash serves a vital ecological role. North American native ash tree species, including the Blue Ash, are critical food sources for North American frogs. The fallen leaves of ash trees are particularly suitable for tadpoles to feed upon in ponds, puddles, and other water sources. However, the emerald ash borer, an invasive beetle, has posed a threat to the survival of many ash tree species. The Blue Ash has shown increased resistance to this beetle, potentially due to its higher tannin content. While this resistance may benefit the Blue Ash, it may result in decreased availability of suitable food for the frogs most threatened by the beetle.
In terms of conservation, the Blue Ash is currently less threatened compared to other North American ash species. Approximately sixty to seventy percent of Blue Ash trees survive the infestation of the emerald ash borer, while other ash species experience higher mortality rates. However, all native ash species face endangerment due to the emerald ash borer's population increase, resulting in their assessment as Critically Endangered.
Overall, the Blue Ash is a remarkable tree with its square twigs, dye-producing inner bark, and versatile wood. Its tolerance of drought and lime makes it a potential choice for street tree planting, and its ecological role as a food source for North American frogs highlights its importance in maintaining a balanced ecosystem. As efforts continue to conserve native ash species, the Blue Ash stands as a resilient and valuable member of the natural world.