Toxic trees and shrubs grow right across Australia. Below is a collection of common trees and shrubs that are toxic to cattle.
Bellyache bush (Jatropha gossypiifolia)
Poisonous parts
All parts are toxic.
Location
Across northern Australia. Infestations often occur on river and creek flats.
Toxin
Toxalbumin.
Symptoms of poisoning
Toxalbumin will cause symptoms of gastroenteritis and will kill some animals.
Cattle will show signs of having a sore stomach and are likely to have severe diarrhoea causing dehydration.
Deaths mainly occur in severe drought when it may be the only feed available.
Treatment / management
Oral rehydration should be the priority in treating affected animals with bentonite or activated charcoal if possible.
Notes
Livestock are more likely to eat bellyache bush when there is not enough other feed.
Bellyache bush is similar to castor oil plant in both appearance and distribution. More information about the control of bellyache bush is available in this fact sheet from Biosecurity Queensland: Bellyache bush.
Additional information, including distribution, photo gallery, and similar plants can be found here.
Castor oil plant (Ricinnus communis)
Poisonous parts
Seeds, and to a lesser extent, leaves.
Location
Castor oil plant is found throughout Australia. It is most abundant along watercourses, floodplains, and disturbed areas.
Toxin
Ricin.
Symptoms of poisoning
Poisoning symptoms do not appear for a few hours or several days. Poisoning from the seeds cause gastrointestinal disorders while the leaves tend to cause neuromuscular disorders, including:
- swaying gait
- low exercise tolerance
- difficulty lying down
- muscle tremors
- salivation
- chewing movements
- excessive belching.
If the animals don’t die within 5-20 hours, they will recover naturally.
Treatment / management
No consistently effective treatment is known. Livestock do not consider castor oil plant to be palatable however will graze it when suitable pastures are unavailable.
Notes
Castor oil plant is similar to bellyache bush in both distribution and appearance. Castor oil plant is unpalatable and rarely grazed when there is sufficient other feed available.
More information about the castor oil plant is available in this fact sheet from Biosecurity Queensland: Castor oil plant; and Atlas of Living Australia, including a distribution map and a comprehensive photo gallery.
Coffee senna (Senna occidentalis)
Poisonous parts
Seedpods.
Location
Coffee senna has naturalised across Queensland, New South Wales, Western Australia and the Northern Territory.
Toxin
N-methylmorpholine from seeds, chrysarobin, toxalbumin and several anthraquinone derivatives.
Symptoms of poisoning
Diarrhoea may be the first sign of poisoning, but the more common clinical signs are associated with the toxin causing muscle tissue damage. Symptoms include:
- dark brown or red urine
- incoordination
- muscle weakness
- excessive salivation
- increased heart rate
- difficulty breathing
- death.
Treatment / management
There is no known treatment for poisoned livestock. Cattle become affected when they have access to dense stands of seedpod bearing plants. Poison or remove the plant where possible, alternatively, restrict grazing access in peak periods of risk.
Notes
Coffee senna is also known as arsenic bush or ant bush. Dogs have reportedly suffered muscle stiffness and an inability to work after eating meat from coffee senna poisoned stock.
These clinical signs are also descriptive of tick fever, however coffee senna poisoning will not cause a fever.
More facts about coffee senna, including distribution map and extensive photo gallery can be found on Atlas of Living Australia: Coffee senna.