Ailanthus altissima

Ailanthus altissima, the ailanthus, tree of heaven, tree of the gods b>, malhuele or false sumac, is an ornamental tree widely used in public gardens in southern Europe, originally from China. Fast growing, it is very resistant to contamination.

Description

It reaches a size of 17 to 27 meters. It can live 40 to 50 years. It is deciduous.

The trunk has gray and cracked bark, with brown tones in older specimens. It has leaves composed of eight pairs of leaflets, long petiolate; They give off the unpleasant odor that characterizes this species. The fruit is a samara that disperses very efficiently; often staying on the tree when it has already lost all the leaves, waiting for gusts of wind.

It was introduced from China in the middle of the 18th century, due to its rapid growth, and following the Chinese fashion of the time., with the intention of repopulating the mountains, however, the poor quality of the wood and its unfavorable characteristics made the project fail.

It is a good colonizer of degraded spaces (solar, open fields), growing even among the ballast of railway lines.

Invasive species

In Spain, and many other areas such as Australia, the United States or southern Europe, it has become an invasive wild species due to its rapid growth and its ability to thrive anywhere, forming dense groves on the margins of the roads. Due to its colonizing potential and constituting a serious threat to native species, habitats or ecosystems, this species has been included in the Spanish Catalog of Invasive Exotic Species, regulated by Royal Decree 630/2013, of August 2, being Its introduction into the natural environment, possession, transportation, trafficking and trade is prohibited in Spain.

The bioecological characteristics of the species make it highly invasive: it is resistant to pollution and a large part of environmental inclemencies, it produces an enormous amount of fruit each year, and it has a great capacity for regrowth. Furthermore, it directly affects the organization and functioning of the ecosystem in which it is established, since it reduces the vegetation cover of the herbaceous stratum due to the projection of shadow and the release of allelopathic substances through its roots, it increases the cover of the tree layer, reduces biodiversity and species richness and increases dominance in favor of itself.

Uses

Active ingredients: contains glycosides, resin, acrid essence, tannins, mucilage.

Indications: it is astringent, anthelmintic, antidiarrheal, rubefacient, emetic. Caution should be exercised when using it internally, since an excessive dose first has a purgative and then an emetic effect.

Other uses: the leaves are used for making paper and as a yellow dye for wool. Its leaves serve as food for a type of silkworm (Samia cynthia).

Taxonomy

The first scientific descriptions of ailanthus were made shortly after it was introduced to Europe by the French Jesuit Pierre Nicholas d'Incarville. D' Incarville had sent seeds from Peking through Siberia to his friend the botanist Bernard de Jussieu in the 1740s. The seeds sent by d'Incarville were believed to be from a similar tree of great economic importance, the Toxicodendron vernicifluum, which he had observed in the lower Yangtze region, rather than ailanthus. D' Incarville attached a note indicating this, which caused much taxonomic confusion in the following decades. In 1751, Jussieu planted some seeds in France and sent others to Philip Miller, the superintendent of the Chelsea Physic Garden, and Philip C. Webb, the owner of an exotic plant garden in Busbridge, England.

The name confusion began when the tree was described by the three men with three different names. In Paris, Linnaeus gave the plant the name Rhus succedanea, while it was popularly known as grand vernis du Japon. In London, the specimens were called by Miller Toxicodendron altissima and in Busbridge it was called in the old classification system as Rhus Sinese foliis alatis. There are extant records from the 1750s of disputes over the proper name between Philip Miller and John Ellis, curator of Webb's garden at Busbridge. Rather than settle the issue, more names for the plant soon appeared: Jakob Friedrich Ehrhart observed a specimen in Utrecht in 1782 and called it Rhus cacodendron.

The issue was clarified somewhat in 1788 when René Louiche Desfontaines observed the samaras of the Paris specimens, which have still been labeled Rhus succedanea, and concluded that the plant did not It was a sumac. He published a paper with an illustrated description and gave it the name Ailanthus glandulosa, placing it in the same genus as the tropical species then known as A. integrifolia(today, A. triphysa). The name is derived from the Ambonese word Ailanto, meaning 'sky tree'; or "tree that reaches to the sky". He gave it as a specific name glandulosa in reference to the glands in the leaves; that name persisted until as late as 1957, but was ultimately invalidated by a late namesake at the species level. The current species name comes from Walter T. Swingle who was hired by the United States Department of Plant Industry. He decided to transfer the older specific name of Miller to the genus of Desfontaines, resulting in the now accepted name of Ailanthus altissima. Altissima is the Latin expression that means & #34;the tallest", and refers to the heights that the tree can reach. This plant is sometimes called, incorrectly, by the specific epithet in the male form (glandulosus or altissimus), but this is not correct because botanists, as in the Classical Latin, treat most tree names as feminine.

Varieties

There are three varieties of A. altissima:

• Ailanthus altissima var. Altissima, which is the type variety and is native to mainland China.
• Ailanthus altissima var. tanakaiwhich is an endemism of the highlands of northern Taiwan. It differs from the type in which it has a yellowish bark, strangely painted leaves that are also of shorter average with 45-60 cm long with only 13–25 fascicles similar to a sickle. It is included in the IUCN Red List of endangered species due to the loss of habitat by construction and industrial plantations.
• A. altissima var. sutchuenensisIt's a difference in that she's got red ribs.

Common names

• Spanish: ailanto, glanulous ailanto, arcacia, Japanese varnish, road goose, malhuele, crazy noguera, oilanto, Chinese tree, sky tree, Japan tree, gods tree, Japan zumaque, fake zumaque.

Pests

A species of Lepidoptera native to America, Atteva aurea, has found an alternative host in the tree of heaven, causing great damage due to herbivory in some specimens.