Thursday, January 25, 2018
Horse Chestnut - Aesculus hippocastanum
The Horse Chestnut - Aesculus hippocastanum, is only native to a very small area of Mountains between Greece and Albania- it was not discovered/recorded until 1596. Once discovered it was rapidly planted and spread almost all over Europe in the early 1600's, then later by the early colonists of North America. It is a very common street tree from Ontario to Virginia. In the West it's spread ranges from British Columbia down through New Mexico, Utah and Colorado. It is one of the more common street trees in the United States and has naturalized in most regions. Growing to heights of 50-75 feet at maturity, this tree can live upwards of 300 years so when planted correctly it can be considered a permanent addition to most landscapes. It is recommended to be planted in hardiness zones 4-7
The name Horse Chestnut was thought to gain it's origin from the false belief that this tree was part of the Chestnut family, combined with the fact that despite the fruits being poisonous to horses they actually cured some chest related ailments when eaten by sick horses.
Image Citations (Photos 1 & 2):Norbert Frank, University of West Hungary, Bugwood.org
Although the Horse Chestnut is sometimes confused with the closley related American Buckeye, that name is generally reserved for the North American members of the Aesculus genus. The Horse Chestnut differs from the American Buckeyes because of it's shiny orange-brown terminal buds, bigger leaves on stalkless leaflets, 1 foot tall heads with predominently white flowers and very prickly husks that enclose the mahogany colored seeds. Each individual flower opens to reveal a bright splash of yellow at the base of every petal, once pollinated this yellow turns a deeper orange and then finally a crimson red.
Image Citations (Photos 3 & 4) :Paul Wray, Iowa State University, Bugwood.org
The flowers provide a rich source of nectar and pollen to insects, especially bees. Caterpillars of the triangle moth and horse chestnut leaf miner moth feed on the leaves. Deer and other mammals eat the conkers. The most famous use of Horse Chestnut is in the game of conkers. The first record of the game is from the Isle of Wight in 1848.
The wood of the Horse Chestnut is soft and often considered weak. It has a very straight light colored grain and is often used for wood turning, artificial limb production and wooden toy making. This weakness can be considered a liability as mature trees in full leaf have been known to drop large branches without warning during heavy storms.