Thursday, July 27, 2017

The "American Elm" - Ulmus americana

The "American Elm" - Ulmus americana" is a medium to large sized deciduous tree that is native to Eastern North America. Found naturally from Nova Scotia, Manitoba, Ontario, Southern Saskatchewan, Montana and Wyoming in the North continuing South through to Florida and Texas. It is an extremely hardy tree and can withstand temperatures as low as -44 degrees F. It's numbers have significantly decreased over the last century due to Dutch Elm disease. The Elm family is made up of about 45 species and are found from Northern and Central Eurasia and Eastern North America South through Panama. Elms are not found in the Rocky Mountains or on the West Coast of North America.

Image Citation: Joseph O'Brien, USDA Forest Service, Bugwood.org

The American Elm is the largest and most widespread of all the Elms in the North America. It grows in a beautiful upright vase shape, and was often used as a focal point or large Ornamental planting along Main Streets and Park areas throughout it's hardiness zones. However, in more recent decades it has been destroyed in many areas by Dutch Elm disease. The leaves are broad and flat, with a simple shape and fine teeth along the edges. They are bright green in color during the growing season and yellow-green to yellow in the Fall. The wood is grained in a fine wavy pattern that is remarkably durable when wet. Elm logs were hollowed out and used during Roman times as water pipes, some have even been unearthed in good condition. The wood wears well and takes well to polish. It has traditionally been used in making coffin boards, stair treads, chairs and paneling. The flowers are perect in form and contain both sexes on one flower. They grow in bunches or on long slender stalks in racemes.

Image Citation: Tom DeGomez, University of Arizona, Bugwood.org

Image Citation: Joseph O'Brien, USDA Forest Service, Bugwood.org

Dutch Elm disease was introduced to the US in 1930 and has been devestating to the American Elm ever since. Dutch Elm disease is recorded in 41 states across the US. The disease is generally characterized by a gradual wilting and yellowing of the foliage, followed by death of the branches and eventually the whole tree. American Elm is also attacked by hundreds of insect species including defoliators, bark beetles, borers, leaf rollers, leaf miners, twig girdlers, and sucking insects. Both birds and mammals feed on fruit and buds, and mammals will chew the bark and twigs of younger trees. Animals and insects are not nearly as damaging to this species as Dutch Elm disease is.

Image Citation: Linda Haugen, USDA Forest Service, Bugwood.org 

The Buckley Elm of Michigan, a National Tree Champion was killed by Dutch Elm in 2001, it was estimated to be over 100 feet tall with a diameter of 8 feet.

The Oklahoma Survivor Tree is a very notable American Elm tree. Standing on the site of the Oklahoma City Bombings it has witnessed and withstood the unimaginable. You can learn more about it by checking out one of my previous blogs: http://destinationtrees.meetatree.com/2015/03/oklahoma-citys-survivor-tree-oklahoma.html

The tallest American Elm on record in New England "Herbie", was located in Yarmouth, Maine. It stood in this location until it too was killed by Dutch Elm disease and had to be removed in January of 2010. Herbie was estimated to be 110 feet tall and 217 years old.

Meet More Cool Trees on our website www.ArundelTreeService.com or our blog www.MeetATree.com

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