Green cestrum (Cestrum parqui) is an medium-sized, branched, erect perennial shrub that is toxic to horses. It is found worldwide, in warmer temperate and sub-tropical regions. C. parqui has shiny, green, lance-shaped leaves and ripe berries. The leaves produce a pungent, foul smell when crushed. The flowers are normally yellow but may have a green tinge and grow in clusters at the end of branches. The flowers produce an unpleasant perfume during the day but can smell quite sweet in the evening. C. parqui berries each contain several wrinkled seeds which are about 3-5 mm long. The dark pulp of the berries will stain fingers a purple color if they are squashed.
All parts of C. parqui are toxic to horses. It contains varying amounts of tropane alkaloids, solanines, and carboxyatractyloside. Ingestion of the plant can result in sudden death in acute cases and severe liver damage if the animal survives the acute toxic episode. C. parqui plants that have been cut down or killed with herbicide will retain poison in their leaves, branches and berries. In fact, recently sprayed wilting plants are more palatable then fresh healthy plants and potentially can cause more deaths.
- Abdominal Pain
- Sudden Death
PHYSICAL CONTROL: Green cestrum can be controlled by repeated cutting down, digging or pushing out by mechanical equipment. All the yellow roots must be removed and destroyed appropriately to prevent regrowth. The roots can be burnt.
CHEMICAL CONTROL: Herbicides are often the most effective and economical way of controlling green cestrum.
Mulch can be used to suppress seedling growth after chemical or physical control. Mulch also retains moisture in the soil and provides protection for native plants that can be sown to replace the green cestrum plants.