Using this manual
Under each poisonous plant discussed in this manual are a number of topics that deserve a word of explanation at this point. When looking for a poisonous plant it is best to check the questionable ones by the description, the illustrations, symptoms/clinical signs of the animal, habitat, and distribution in the state.
Description
Descriptions of the plants are brief and in many cases general; often, closely related species can be distinguished only by a specialist. Descriptive terms are explained in the glossary. Illustrations are given for those plants most likely to cause serious poisoning or death. Anyone in North Carolina may send in questionable plants for identification and information. Specimens can be sent fresh in a plastic bag, or pressed and dried between folds of newspaper for two to three days. Usually definite identification can be made only if the flower or fruit and an entire twig with leaves are sent in.
Send specimens to:
Department of Botany, Campus Box 7612
NC State University
Raleigh, NC 27695-7612
Habitat
The types of habitats in which the species is usually found are given. In general, a plant species is more or less restricted to a particular type of environmental condition, although some are found in many different habitats.
Distribution
The general range of each species is described and maps are given for those not found throughout the entire state. Shading on the maps indicates the general area in which the species grows. Written distributions usually are given in terms of the three physiographic provinces in North Carolina (Map 1). Note that the piedmont is subdivided here into upper and lower, relative to elevation rather than to north and south. Little can be said about the distribution of cultivated plants or those that escape cultivation, except to point out where they are usually found, since presumably most could grow throughout the entire state.
Group Number
Because conditions under which poisonous plants are eaten are so variable, and because there are so many factors influencing the degree of poisoning, any ranking or grouping of plants on the basis of their relative importance is purely arbitrary and subjective. Any one plant may be thought relatively unimportant and yet, under a certain set of circumstances, may cause the fatal poisoning of a whole herd of cattle.
For this reason, plants described here are arranged by family and not by their relative importance. However, they are placed in one of five groups based on past history of poisoning in North Carolina. These five groups are as follows:
GROUP 1. Those that are most likely to cause serious poisoning or death.
GROUP 2. Those that may cause serious poisoning or death, but are eaten rarely by livestock.
GROUP 3. Those that may cause serious poisoning or death, but are uncommon in North Carolina.
GROUP 4. Those that cause only minor disorders or irritation.
GROUP 5. Miscellaneous cultivated plants of the house, field, and garden that may cause poisoning but are usually unavailable to livestock but may be available to house pets.
Poisonous Principle
When known, the kind of poison is given. Often the type of treatment may depend on the type of poison. The different poisonous substances are described in a later section.
Parts of the Plant
Detailed pictures or drawings are provided, and the specific portions of the plant that are poisonous are named. Notes on this topic are given so that pet and livestock owners can see which parts may have been grazed. Also, in the case of flowers or seeds, the plants may be controlled by cutting or pruning early in the season.
Periodicity
Although most poisonous plants are dangerous throughout the year, or growing season, many are most dangerous during certain seasons. For example: heaths (laurel, fetterbush, and others) are dangerous during the winter because of their evergreen nature, which makes them one of the few types of green vegetation available. Water hemlock is most dangerous in early spring because it is one of the first green plants to appear; it becomes relatively coarse and unpalatable later in the summer. Some plants are toxic by accumulation; that is, fresh material or plants dried in hay or other feed can cause harm when eaten over a long period of time rather than when ingested in a single feeding.
Animals Poisoned
The most dangerous plants are usually poisonous to all livestock, but occasionally only poultry or swine or cattle may be affected by a particular species. Some animals, by nature of the way they eat, may graze a particular plant or plant part that is unavailable to other animals. Also, because of physiological differences among different kinds of animals, a plant may be readily grazed by deer, for instance, but be poisonous to cattle or horses.
Symptoms/Clinical Signs
There is disagreement in the literature about the various symptoms/clinical signs of poisoning. These are quite variable and are usually not specific for particular plants. Early diagnosis is important in controlling losses by poisonous plants. In cases of suspected poisoning call a veterinarian as soon as possible, and move the livestock from the area where the poisoning occurred. You should survey the stock often to catch symptoms early while a remedy may still be possible. However, most of the damage may have been done by the time the sick animal is discovered, and too often poisoning is only noticed after the animal has died.
Abortions in livestock are often caused by an animal eating some poisonous plant in sufficient quantity to cause abortion but not enough to kill the animal or even cause outward symptoms. Abortions in cows have been caused by Gelsemium, Phytolacca, Cicuta, Conium, and by nitrate poisoning.
Treatment
Call a veterinarian! Remove animals from pasture or their feed!
For all practical purposes, treatment of plant-associated poisoning is symptomatic and supportive and no generally accepted antidotal agents are available. There are some exceptions, such as the treatment for nitrate/nitrite poisoning. In many cases, however, there is no particular treatment recommended, and, generally, specific treatments and dosages of the many curative drugs have not been included here because they vary so greatly. In some cases the drugs used for treatment may even be poisonous in improper doses. Try to find and identify the poisonous plant, but leave the treatment to the veterinarian.
Necropsy
If an animal dies of unknown causes, it is wise to request that your veterinarian perform a postmortem examination. Finding the cause, by clinical signs, may lead to a definite diagnosis and may suggest a means of safeguarding the remainder of the herd. Information on necropsy is given for veterinarians.
Site developed by Krings, 2000
