The Black Locust is a memeber of the Pea Family.  It grows quickly and can reach heights between 40 and 100 feet.  The bark of mature trees is dark and has deep grooves with flat ridges (5).  

The leaves of the Black Locust are alternate, compound, and have seven to twenty-one leaflets.  Each leaflet is oval in shape (5).  Thorns can be found at the base of the leaf stalk.  At night the leaflets droop and the leaf seems to be folding up.  The undersides of the leaves are pale and the tops are dark green.  In the fall the leaves turn yellow.

The white flowers of the black locust appear in late spring and are found in drooping clusters (5).  

The fruit of this tree is a pod that is two to four inches long and contains four to eight seeds (5).  The pods hang on the tree throughout the winter (8).

Location on Campus

The Black Locust on campus is found just south of the White House (4141 East Ave) and just north of parking lot C.

Native Habitat and Current Range

Leaves of the Black Locust (11)

The Black Locust is native to the southeastern United States and can be found in the southern Appalachians, Virginia, the lower Ohio Valley, and in the Ozarks (4).It was introduced into Europe during the 1600s (4). It has since become an invasive species there.

Optimal Growing Conditions

Fruit of the Black Locust (11)

The Black Locust grows best in full sun and well drained soil where there isn’t a lot of competition.  It has also been found growing in disturbed areas such as fields and along road sides (5).

Economic Importance

Bark of the Black Locust (9)

The Black Locust is the only species of locust that is important for its timber.  The wood is often used for fence posts and hardwood lumber, and is also valued as a source of fuel (12). It is widely planted throughout the Eastern United States and parts of Europe for various reasons including erosion control and to increase soil fertility via nitrogen fixation (7). Black Locusts are also often planted for shade or for ornamental purposes (8).  The flowers provide a good source of nectar for honeybees (5).

 

Ethnobotanical and Cultural Information

Flowers of the Black Locust Taken by Kathy Bolin (5)

Virginian Native Americans used the wood to make bows.  Wood from the Black Locust was used for the corner posts of the colonists’ first houses (2).Components of the roots of the Black Locust were used to induce vomiting, to reduce a toothache, and to cure a headache.  The bark was once used to add flavor to medicines (10). The seeds are eaten by birds and some small mammals.  They have even been used as a substitute for coffee (1).

Fascinating Facts

• Other names common names for the Black Locust include: Yellow, White, Red, Green, Post, Honey Locust, and False Acacia (4).

• Black Locusts can live to be 60 to 80 years old (3).

• Horses are most likely to be poisoned by Black Locusts because they will chew on the bark or leaves for food when nothing else is available (6).

• Locusts are subject to attack by a wood boring insect, Cyllene robiniae (7).

Other interesting sites

http://www.biosurvey.ou.edu/shrub/rops.htm
This site contains descriptions of leaves, flowers, fruits, bark, etc.

http://www.hort.purdue.edu/newcrop/proceedings1993/V2-432.html
This site has some more ecological information about Black Locusts.

http://www.hort.agri.umn.edu/h5015/00papers/sabo.htm
This site contains some information about the invasiveness of the Black Locust and how to control it.

References: Articles, Books, Reference Materials, and the Web

1. Domtar Inc.  2003.  Black Locust.  <http://www.domtar.com/arbre/english/p_roaca.htm>  Accessed 2003 Nov 14.

2. eNature.com  2003.  Black Locust.  <http://www.enature.com/fieldguide/showSpeciesRECNUM.asp?recnum=TS0146>  Accessed 2003 Nov 14.

3. Ostermiller S.  1997.  Black Locust.  <http://www.ostermiller.org/tree/blacklocust.html>  Accessed 2003 Nov 14.

4. Peattie DC.  1966.  A natural history of trees of eastern and central North America.  Boston: Houghton Mifflin Company.  606 p.

5. Plant Conservation Alliance.  1998.  Black Locust.  <http://www.nps.gov/plants/alien/fact/rops1.htm>  Accessed 2003 Nov 14.

6. Purdue University.  1999.  Black Locust.  <http://www.vet.purdue.edu/depts/addl/toxic/plant48.htm>  Accessed 2003 Nov 14.

7. Record SJ, Hess RW.  1972.  Use and abuse of America’s natural resources.  New York: Arno Press.  640 p.

8. Rogers JE.  1905.  The tree book.  New York: Doubleday, Page & Company.  589 p.

9. The Nature Conservancy.  2003.  Wildland Invasive Species Team  Robinia pseudoacacia. <http://tncweeds.ucdavis.edu/esadocs/robipseu.html>  Accessed 2003 Nov 18.

10. University of Michigan Dearborn.  2003.  <http://herb.umd.umich.edu/>  Accessed 2003 Nov 14.

11. Virginia Department of Forestry.  2003.  <http://www.vdof.org/mgt/trees/locust-black.shtml>  Accessed 2003 Dec 1.

12. Wisconsin Department of Natural Resources.  2003.  Black Locust.   <http://www.dnr.state.wi.us/org/land/er/invasive/factsheets/locust.htm>  Accessed 2003 Nov 14.