• Certain ash trees bear ornamental fruit.mountain ash tree, ashberry, rowa-tree image by Canoneer from Fotolia.com
  
  Although there are over 70 species of ash tree in the world, only a handful of those are regularly used in landscaping. Ash trees are enjoyed for their oval-shaped growth habit and profuse, slender leaves, which provide abundant shade. Ash trees are hardy trees but are susceptible to pests such as the emerald ash borer, a wood-boring beetle that currently threatens millions of trees across America.
  
  

European Ash

• The fast-growing and resilient European ash is a popular tree with landscapers and gardeners in the northern United States. Native to Europe, the European ash is found in abundance across the continent with the exception of the southern area of the Iberian Peninsula. Growing to a height of over 100 feet, the European ash is a large tree with a spreading habit, making it an effective shade tree. Like most varieties of ash tree, the European ash is slow to leaf in the spring but will produce an abundance of foot-long pinnate leaf structures with 7 to 12 slender, serrated leaflets.
  
  

Blue Ash

• Native to the Midwest and parts of the American south, the blue ash is a medium-sized tree that grows up to 80 feet tall. Blue ash trees have a relatively narrow trunk that only reaches 40 inches in diameter, but the compact grain of the wood makes it exceptionally sturdy. The blue ash blooms early in the spring before producing 14-inch long leaf structures that bear up to 11 leaflets, each with a serrated edge. In autumn, the blue ash bears abundant two-winged fruit, commonly referred to as whirligigs or keys.
  
  

White Ash

• The white ash is found throughout the eastern United States and Canada, from Nova Scotia to Florida and is one of the longest living ash trees, often reaching 300 years of age. The white ash is similar in growth habit and production cycles to most other ash trees, bearing flowers in the early spring, serrated leaves in summer and fruit in the autumn. Often confused with the green ash, the white ash is identifiable by the pale undersides of its leaves. The white ash wood is widely used by woodworkers, most famously in the production of baseball bats.
  
  

Green Ash

• The green ash is the most widely distributed ash tree in the United States, with a range that stretches from eastern Canada and the Atlantic seaboard to central Montana. The green ash is among the most commonly planted ornamental trees due to its attractive growth habit and resiliency to disease and extreme temperatures. The average height of green ash trees is 60 feet, although certain specimens have been measured at heights exceeding 150 feet. The green ash changes color early in the autumn, from light green to golden yellow. The only serious concern when planting green ash trees is its susceptibility to the emerald ash borer, which is a wood-boring beetle that damages the structural integrity of the tree.