Clover Elm ( Ptelea trifoliata )
The clover elm ( Ptelea trifoliata ), also called leather bush , leather sleeve tree or hop bush , is a deciduous shrub or small tree with a broad crown. It belongs to the diamond family and is native to North America .
The small tree or large shrub has several diverging trunks. It has thick fleshy roots. The bark is reddish to gray-brown, has short horizontal lenticels and warty cork-like elevations that are slightly scaly.
The branches are rather thin, brown, and have deep U-shaped leaf stigmas and short, light brown, fluffy buds. The leaves are alternate, 5–18 cm long and consist of three (rarely five) leaflets, each 1–10 cm long, slightly to completely serrated, shiny dark green on the upper side and paler on the underside. The western and southwestern forms have smaller leaves (5–11 cm) than the eastern variants (10–18 cm) for climatic reasons.
The flowers are small, 1–2 cm in diameter, with 4–5 narrow, greenish-white petals and appear in groups in spring at the end of the branches. Some find the smell unpleasant, others find it nice. The fruit is a disc-shaped round samara with a diameter of 2–2.5 cm. It is light brown and ripens in summer. It is surrounded all around by a thin wing, stays on the tree and is spread by the wind ( anemochory ). It smells pleasantly of citrus fruits.
The number of chromosomes is 2n = 42.
The species is naturally found in shady locations along forest edges, especially on the rocky slopes of the Mississippi Valley. It prefers moist, well-drained, fertile soils. It is quite drought resistant .
De Kleeulme is planted in gardens. It is one of the few American small trees that can tolerate full shade.
The vegetable juices are bilious and bitter. The bark has an unpleasant odor and bitter taste and is used in herbal medicine by the Native Americans for various applications. It is also used in homeopathy .
Taxonomy and systematics
Although mostly viewed as a species with multiple varieties or subspecies, some botanists suggest a group of four or more closely related species:
- Eastern native to North America ( Ptelea trifoliata var. Trifoliata , Ptelea trifoliata sensu stricto)
- Florida clover elm ( Ptelea trifoliata var. Baldwinii ( Torr. & A. Gray ) DB Ward , Syn .: Ptelea baldwinii Torr. & A. Gray )
- Narrow-native to North America ( Ptelea trifoliata var. Angustifolia (Benth.) MEJones , Syn .: Ptelea angustifolia Benth. , Ptelea lutescens Greene , Ptelea trifoliata L. subsp. Angustifolia (Benth.) VL Bailey )
- Ptelea trifoliata L. subsp. coahuilensis (Greene) VL Bailey , Syn .: Ptelea coahuilensis Greene : It occurs in Mexico.
- Ptelea trifoliata L. subsp. pallida (Greene) VL Bailey , Syn .: Ptelea pallida Greene : It occurs in Colorado, Utah, Arizona and New Mexico.
- Ptelea trifoliata L. subsp. polyadenia (Greene) VL Bailey , Syn .: Ptelea polyadenia Greene : It occurs in Oklahoma, Arkansas, Arizona, Texas and New Mexico.
- Description of the Kleeulmue ( Memento of the original from July 1, 2007 in the Internet Archive ) Info: The archive link was inserted automatically and not yet checked. Please check the original and archive link according to the instructions and then remove this notice. , Botanical Garden of the Ruhr University Bochum
- Harriet L. Keeler: Our Native Trees and How to Identify Them . Charles Scriber's Sons, New York 1900, pp. 32-35.
- Ptelea trifoliata at Tropicos.org. In: IPCN Chromosome Reports . Missouri Botanical Garden, St. Louis
- Edward F. Gilman, Dennis G. Watson: Ptelea trifoliata, Common Hoptree . USDA Forest Service Fact Sheet ST-530, 1994. (pdf)
- Ptelea in the Germplasm Resources Information Network (GRIN), USDA , ARS , National Genetic Resources Program. National Germplasm Resources Laboratory, Beltsville, Maryland. Retrieved June 11, 2017.