Tree Indiana Native Fraxinus quadrangulata [Blue Ash] The Blue Ash earned its common name from the blue dye made by early Americans from the inner bark, which contains a substance that turns blue with exposure to air. This tree is naturally found upland in dry, rocky limestone areas and is very drought tolerant. As with all ashes, Fraxinus quadrangulata is extremely susceptible to the Emerald Ash Borer. Damage from this pest can be prevented with the soil drench method imidacloprid, but the…
