Field Guide to Plants Poisonous to Livestock: Western U.S.

Lantana spp.

Common name: Lantana
Family: Vervain
Region: U.S.
Habitat: Streamsides, ornamental
Toxic season: Spring and summer
Features: Shrub may reach 4' tall. Leaves opposite, egg-shaped, hairy, rough, toothed. Flowers white, pink or yellow, 5-petaled spreading out trumpet-like from thin tubes, clustered. Fruits are black, shiny berries, also clustered. Seeds oval, grooved, rough, brown.
Poison type: Triterpenoid compounds (lantadenes)
Signs/effects: Acute: severe bloody diarrhea, weakness, rapid heart rate, labored breathing, jaundice, death in 3-5 days. Chronic: photosensitization due to liver damage, labored breathing, constipation, swollen eyelids, possibly eventual death. Kidney damage also possible.
Treatment: Remove animals from access to plants, provide supportive treatment. Activated charcoal early after ingestion may revent absorption. Bentonite clay may also be effective. If photosensitization occurs, shelter animal from light and treat topically to avoid infection. If acute, cautious use of physostigmine may be considered.
Comments: Leaves and fruits (esp. green, unripened) are toxic. All livestock are susceptible, especially ruminants. Serious illness may occur with ingestion of 1% of body weight in green plant matter. Toxic to humans.

© Copyright 1998 by Shirley A. Weathers