Select a Plant by:


BLACK WALNUT

Juglans nigra

BLACK WALNUT PLANT BLACK WALNUT PLANT BLACK WALNUT PLANT BLACK WALNUT PLANT
(67K) (38K) (69K) (32K)

For additional images, click:

Select an image to see a magnified version. Note the file size beneath each image since large files will take longer to load from home with a modem.

 
Description. Walnut trees are 50-100 meters tall and have dark, deeply furrowed bark, alternate pinnately compound leaves with approximately 20 leaflets and a spherical fruit 3-7 centimeters in diameter.  A thick green husk breaks open to reveal a hard, brown, furrowed nut.
Geographic range black walnut trees range widely throughout the eastern United States as far west as the Missouri river.  They prefer the moist, rich soils of bottom lands.
Exposure: shavings or sawdust from walnut trees is occasionally used as animal bedding.  Horses are most at risk.
Toxic principle: unknown.  A compound known as juglone has been suspected to be the toxin, but efforts to document this have been inconclusive.
Diagnosis

Clinical signs in horses occur within 24 hours of exposure to walnut shavings and include rapid onset of laminitis, a digital pulse, distal edema of the limbs, polypnea and elevated temperature.  Necrosis of the dorsal laminae may occur and complicate recovery.

 Laboratory diagnosismicroscopic examination of the bedding for the presence of walnut shaving confirms exposure.

 Lesionsconsistent with laminitis.

Treatment
  • The source of the walnut should be removed, and gastrointestinal detoxification carried out using mineral oil or activated charcoal and a mild cathartic.
  • The legs and feet should be washed.
  • Phenylbutazone or acepromazine can be used to treat pain associated with laminitis.
CLICK ROR ANIMAL LESION


 


Copyright 2002

University of Pennsylvania
Created by:    Alexander Chan (2003), Daphne Downs (2002), Chris Tsai (2001), Brett Begley (2000), Janet Triplett (1997)
Faculty Advisor:  Dr. Robert Poppenga