St John’s Wort
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St John’s Wort
Names: Hypericum perforatum, klamathweed, goatweed
Description: Perennial that grows up to three feet. Stems have woody base and reddish stems. Leaves are small and oval and grow opposite. Flowers are bright yellow and may have black dots on the edges of petals. Fruit is in a capsule with dark brown seeds.
Concern level: Adult plant is unpalatable, the young plant is attractive to grazers. However concern should be high due to it’s extreme toxicity.
Toxic parts: All parts of the plants are toxic.
Symptoms: Occur within 24 hours of ingestion, nflammation, redness and ulceration of light colored skin, lack of appetite, severe itching, blindness, convulsions, coma.
Danger: Contains Hypericin which causes a chemically induced sunburn on light colored skin. Can be fatal.
More information: Herbs at a Glance
Poisonous plants by letter
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Q
R
S
T
U
V
W
X
Y
Z
Looking for a plant but don't know the name? Try the toxic plant identifier
This information is for reference only, if you think your horse has eaten something toxic, call your vet right away.
