Hemp Dogbane
Latin Name: Apocynum cannabinum
Identifying Characteristics:
- 2-6 feet tall
- Woody stem
- Opposite leaves (2 leaves per node)
- Smooth leaf edge
- Flowers are arranged in clusters
- Opposite venation on leaf midrib
- Internal sticky milky sap
- Underground rhizomes (horizontal stems)
Plant Longevity:
- Perennial
Where Commonly Found:
- Moist areas
- Near streams
- Roadsides
- Waste areas
- Pastures
Time of Most Concern:
- Late spring up until early fall
Compound that Causes Concern:
- Cardiac glycosides
Part of Plant Most Toxic:
- Any green part of the plant or dried hay
Livestock Species Affected:
- Cattle
- Horses
- Sheep
- Goats
Pasture, Stored Feed, Both:
- Both
Clinical Signs:
- Rapid pulse
- Dilated pupils
- Convulsions
- Vomiting
- Death
Amount Needed to be Consumed for Clinical Signs / Death:
- 0.5gm/kg (0.0023 oz/lb) of animal’s body weight
- 2.3 oz in a 1,000 lb cow
- 15 g (0.5 oz) of green leaves have been reported to cause death in some cows
Identifying Characteristics:
- 2-6 feet tall
- Woody stem
- Opposite leaves (2 leaves per node)
- Smooth leaf edge
- Flowers are arranged in clusters
- Opposite venation on leaf midrib
- Internal sticky milky sap
- Underground rhizomes (horizontal stems)
Plant Longevity:
- Perennial
Where Commonly Found:
- Moist areas
- Near streams
- Roadsides
- Waste areas
- Pastures
Time of Most Concern:
- Late spring up until early fall
Compound that Causes Concern:
- Cardiac glycosides
Part of Plant Most Toxic:
- Any green part of the plant or dried hay
Livestock Species Affected:
- Cattle
- Horses
- Sheep
- Goats
Pasture, Stored Feed, Both:
- Both
Clinical Signs:
- Rapid pulse
- Dilated pupils
- Convulsions
- Vomiting
- Death
Amount Needed to be Consumed for Clinical Signs / Death:
- 0.5gm/kg (0.0023 oz/lb) of animal’s body weight
- 2.3 oz in a 1,000 lb cow
- 15 g (0.5 oz) of green leaves have been reported to cause death in some cows