BLACK WALNUT (Juglans nigra) – Black walnut is a large tree growing in rich forest soils throughout Ohio. Leaves are alternate and are pinnately compound with numerous toothed leaflets. The twigs have a characteristic chambered pith. Black walnut fruits consist of a nut surrounded by a thick husk and do not split open when ripe.
The toxic phenolic compound, juglone, is found in the bark, wood, nuts, and roots of black walnut. Horses are primarily affected when exposed to shavings that contain black walnut wood. Shavings contaminated with less than 20% black walnut can cause poisoning in 24 hrs. Affected horses exhibit depression, lethargy, laminitis, distal limb edema, and increased temperature, pulse, respiration rate, abdominal sounds, digital pulse, and hoof temperature. Consumption of the shavings may also cause signs of mild colic. Symptoms usually disappear within a few days after shavings are removed.
Horses on pasture may show mild respiratory signs from pollen or fallen leaves.
Black walnut toxicity - jugulone (aka 5-hydrocy-1,4-naphthoquinone
yellow aromatic oil
toxicity to horses from direct contact (shavings) or ingestion
direct contact - laminitis, reluctance to move, limb edema, incresed limb pulses
ingestion - dark staining mucosa of mouth, lips
believe this is primarily a problem of horses (not ruminants) but will investigate.....dl (cow)
Perhaps (probably) this a coincidence, but I had a 3 1/2 year old cow die two months ago right next to the dry creek. Full of Black Walnut trees. I found her just laying down like she was chewing her cud, no signs of distress, just dead, laying under one of the trees.
Dogs can be affected by walnut poisining. So "justme" keep the corgi's away from the nuts!
I didn't see anyother species that are bothered except for man. I remember my mother-in-law used to gather them up & crack them. Her hands would get dyed black from the hulls. She finally got smart & put them in the driveway & let the trucks run them over to break the shells.