Iowa is well supplied with four species of ash trees. They are white, green, blue, and black. Ashes range from medium to large in size, attaining a height of from 80 to 90 feet, with the green and white ash growing the largest. They all do best on a moist soil, but can adapt to a variety of conditions.
Green ash can be grown easily from seed and has been planted extensively throughout the state. Green ash is found mostly on flood plains when growing in its natural state. Blue ash and white ash are not considered to be flood plain trees, and are found growing on well-drained bottomlands and moist slopes. Blue ash is restricted to the extreme southeast corner of the state. White ash is the most important of the four from a commercial standpoint.
All of the ashes have opposite-branching and pinnately compound leaves which almost immediately identify them. The ashes have five or more leaflets. The seeds look like miniature canoe paddles -- a double samara.
White Ash - Fraxinus americana
White Ash: Flower, Leaf, and Seed (Photos by: Paul Wray)
White Ash: Twig (Photos by: Paul Wray)
Green Ash - Fraxinus pennsylvanica
Green Ash: Flower, Leaf, and Seed (Photos by: Paul Wray)
Green Ash: Twig (Photos by: Paul Wray)
Blue Ash - Fraxinus quadrangulata
Blue Ash: Twig (Photos by: Paul Wray)
Black Ash - Fraxinus nigra
Black Ash: Flower, Leaf, and Seed (Photos by: Paul Wray)
Black Ash: Twig (Photos by: Paul Wray)