Kentucky coffeetree

TheKentucky coffee tree(Gymnocladus dioicus), also known asAmerican coffee berry,Kentucky mahogany,nicker tree, andstump tree,is atreein the subfamilyCaesalpinioideaeof the legume familyFabaceae, native to theMidwest,Upper South,Appalachia, and small pockets ofNew Yorkin theUnited StatesandOntarioinCanada. The seed may be roasted and used as asubstitute for coffeebeans; however, unroasted pods and seeds are toxic. The wood from the tree is used bycabinetmakersandcarpenters. It is also planted as astreet tree.
From 1976 to 1994, the Kentucky coffeetree was the state tree ofKentucky, after which thetulip poplarwas returned to that designation.
The tree varies from 18 to 21 meters (60–70 feet) high with a spread of 12–15 meters (40–50 feet) and a trunk up to one meter (3 feet) in diameter. The tree grows at a medium rate with height increases of anywhere from 12" to 24" per year.A 10-year-old sapling will stand about 4 meters (13 feet) tall. It usually separates 3 to 4½ meters (10–15 feet) from the ground into three or four divisions which spread slightly and form a narrow pyramidal head; or when crowded by other trees, sending up one tall central branchless shaft to the height of 15–21 m (50–70 ft). Branches are stout, pithy, and blunt; roots are fibrous.
TheKentucky coffeetreeis a moderately fast-growing tree, and male trees are often grown in parks and along city streets for ornamental purposes. The tree is typically fairly short-lived, healthy trees living from 100 to 150 years.The Kentucky coffeetree sheds its leaves early during the fall and appears bare for up to 6 months. The naked appearance of the tree is reflected through the Kentucky coffeetree's Greek genus name, which means "naked branch".Like theSumac, branches are absent of fine spray; smaller branches are thick and lumpish. Because of the absence of smaller branches and its later leafing, the French in Canada named itChicot, "stubby". The expanding leaves are conspicuous because of the varied colors of the leaflets; the youngest are bright pink, while those which are older vary from green to bronze.
The bark is ash-gray and scaly, flaking similarly toblack cherry, but more so. The trees aredioecious, and thefruitis a hard-shelled bean in heavy, woody, thick-walled pods filled with sweet, thick, gooey pulp. Pod length ranges from 5 to 10 inches (130 to 250 mm); unfertilized female trees may bear miniature seedless pods. The beans are commonly thought to contain thetoxincytisine, although this has yet to be confirmed in a study.
Gymnocladusis derived from theAncient Greekκλάδος(kládos) "branch" andγυμνός(gumnós) "naked" and refers to the stout branchlets unclothed with small twigs.
It is one of five species in the genusGymnocladus, and the only one native toNorth America; the other four being native to South, Southeast and EasternAsia.
The name is sometimes hyphenated as 'coffee-tree'; the form 'coffeetree' here is as used officially by theUnited States Forest Service.
The Kentucky coffeetree is considered a rare tree species. "Rare species are those that are so uncommon that they should be monitored to determine whether their populations are becoming threatened."It is widely distributed, but rare.
The tree's native range is limited, occurring fromSouthern Ontario, Canada and in the United States fromKentucky(where it was first encountered by Europeans) andConnecticutin the east, toKansas, easternNebraska, and southeasternSouth Dakotain the west, to southernWisconsinandMichiganin the north, and to northernLouisianain the south. It is planted as an urban shade tree across the United States and eastern Canada, including California.It has adisjunct populationinCentral New York.
This tree usually occurs as widely dispersed individuals or small colonial groups with interconnected root systems. This tree is found in floodplains and river valleys but is also sometimes seen on rocky hillsides and limestone woods. In the northeastern part of its range, seemingly natural groves of this tree are actually associated with known prehistoric village sites. In some parts of its range, this tree may be used as an indicator of the presence of limestone or of calcareous soils.
The Kentucky coffeetree is considered an example of anevolutionary anachronism.The tough, leathery seed pods are too difficult for many extant animals to chew through (in addition to being poisonous) and they are too heavy for either wind or water dispersal. It has been hypothesized that the tree would have been browsed upon by now-extinct mammalian megafauna,which ate the pods and nicked the seeds with their large teeth, aiding in germination. This behavior is seen amongAfrican elephantseatingFabaceaerelatives in Africa. Because of this, its prehistoric range may have been much larger than it has been in historical times. Today, in the wild, it only grows well in wetlands, and it is thought that only in such wet conditions can the seed pods rot away to allow germination in the absence of large herbivores.
Gymnocladus dioicusis considered well-suited to urban environments, as it is tolerant of poor soils, has extreme drought tolerance, and is not vulnerable to serious insect infestations or disease problems.It is cultivated by specialty treeplant nurseriesas anornamental treefor planting ingardensandparks. The peculiarly late-emerging and early-dropping leaves, coupled with the fact that the large leaves mean few twigs in the winter profile, make it a tree that is ideal for urban shading where winter sunlight is to be maximized (such as in proximity tosolarhot-air systems).
It is often planted because of its unique appearance and interesting character.There are several Kentucky coffeetrees atMount Vernon, in the gardens along the path leading up to the house ofGeorge Washington.
Trees prefer a rich moist soil, such as bottom lands.Their growth is largely unaffected by heat, cold, drought, insects, disease, road salt, ice, and alkaline soil.
Kentucky coffeetree is easy to grow from seed. Filing the seedcoat by hand with a small file, and then soaking the seeds in water for 24 hours will ensure rapid germination.Propagationis also easy from dormantroot cuttingsfrom December through March.
The Kentucky coffeetree is typically found on "alluvial soils of river and flood plains and nearby terraces".Here it may be locally abundant and form largeclonal colonies, reproducing by shoots sprouting from roots.
The beans of the tree were eaten, after roasting, in theMeskwaki(Fox),Ho-Chunk(Winnebago) andPawneeNative American cultures.
The Meskwaki also drank the roasted ground seeds in a hot beverage similar to coffee.The common name "coffeetree" derives from this latter use of the roasted seeds, which was imitated by settlers because it seemed asubstitute for coffee,especially in times of poverty, similar tochicory. The European colonialists, however, considered it inferior to real coffee:
The roasted seeds can be eaten like sweet chestnuts.Usefully, the fruits can be collected and picked up from the tree or ground at any time during fall, winter, and spring.
Caution should be used when consuming, as unroasted or only partially roasted beans and pods are considered poisonous and are reputed to contain the alkaloidcytisine.The pods, preserved like those of thetamarind, can be eaten and are slightly aperient (laxative).Many sources claim that roasting the seeds for a certain length of time can reduce or eliminate the cytisine thought to be in them, but this is not based on scientific evidence. There are however, many anecdotal accounts of people drinking a coffee-like drink made from the seeds without suffering any adverse health effects, although most reported the taste to be unpleasant.
The plant is toxic to some animalsand may intoxicate dogs.
In addition to use as a food, the seeds of Kentucky coffeetree were used byNative Americansfor ceremonial and recreational purposes. Seeds were used as dice ingames of chancethat were common in eastern tribes. It is likely that indigenous community members carved patterns on coffeetree seeds used in ceremonial dice games, which also served to scarify the seeds and prepare them for germination.The seeds were also used in jewelry. The importance of the Kentucky coffeetree to Native Americans undoubtedly contributed to its dispersal.
Gymnocladus dioicusis used as a street tree as far north asQuébec city,Québec. It resists harsh winters and de-icing salts.
The wood is used both bycabinetmakersandcarpenters. It has very littlesapwood.
A specimen with a height of 26 metres (85 ft) was referenced in La Turpinerie, commune ofGeay, a short distance from theCharentein south-west France, growing in a typical calcareous soil (see Minutes of Congrès international de sylviculture de Paris, June 1900). Cut during the 20th century, it had a circumference of 2.8 metres (9 ft 2 in) and was the tallest in the country at this time.
A Kentucky coffeetree, said to have been brought to theUKin 1812, stands inMountsfield Parkin theLondon Borough of Lewisham.
A Kentucky coffeetree found in the Will Rogers Park inAmarillo, Texashas been confirmed to be the largest of its kind inTexas.Texas A&M Forest Service said, has a circumference of 92 inches, a height of 51 feet and a crown spread of 52 feet.
A Kentucky coffeetree lives in Rhode Island in theRoger Williams Park Zooat 1000 Elmwood Avenue, Providence.
At theU.S. Space & Rocket CenterinHuntsville, Alabama, 19 Kentucky coffeetrees are planted in the Apollo courtyard prior to entry into the museum.
In 2022, the Tree Board for the town of Hillsborough, North Carolina, selected a grove of Kentucky coffeetrees as its 2022 Treasure Tree. Originally the grove was mis-identified as a part of a program to remove invasive species, but the North Carolina Forest Service helped to confirm the proper identification of the trees.
The largest Kentucky coffeetree inNew Hampshire, at 91 ft tall, is on the campus ofDartmouth College.