Part 1

Produced by Tom Cosmas compiled from images made available by The Internet Archive.

Transcriber Note

Text emphasis is denoted as: Italics and =Bold=.

POISON-ivy

POISON-oak

and

POISON sumac

IDENTIFICATION PRECAUTIONS ERADICATION

Farmers' Bulletin No. 1972

U. S. DEPARTMENT OF AGRICULTURE

POISON-IVY, poison-oak, and poison sumac remind most people of painful experiences to be avoided, yet many do not know any one of the offending plants or their equally poisonous relatives. Learning to recognize them on sight is relatively easy, especially by examining the distinctive identifying characters described in the pictures and legends of this bulletin. There is then a good chance to avoid them or, if one must work among them, to take preventive measures to escape poisoning.

These plants are very common throughout the United States. They are found in fields and woods, along fence rows, rock walls, and hedges, in lawns and gardens, and even sometimes vining on houses. Usually in any one locality it is necessary to be certain of the identity of only two or three of them. Maps show at a glance where they are likely to be found. Frequent observation and recognition of the plants as they are encountered almost daily is the best way to become poison-oak or poison-ivy conscious. Nonpoisonous sumacs are easily distinguished from the poisonous species by the seed heads and leaves.

The old proverb, "an ounce of prevention is worth a pound of cure," is good advice to everyone, particularly as regards ivy-poisoning. Previous escape is not proof of immunity when conditions are right, and after poisoning occurs there is no quick cure known. Some relief may be obtained and recovery hastened by use of some of the tested remedies. In case of severe poisoning a physician should be consulted.

Poison-ivy and other poisonous plants growing in grounds frequented by people should be eradicated. In some places this can be done by careful grubbing. In others weed-killing chemicals may be better and more certainly would avert poisoning for most of us.

This bulletin supersedes Farmers' Bulletin 1166, Poison Ivy and Poison Sumac and Their Eradication.

Washington, D. C. Issued August 1945

POISON-IVY, POISON-OAK, AND POISON SUMAC: IDENTIFICATION, PRECAUTIONS, ERADICATION

By Donald M. Crooks, principal horticulturist, Division of Tobacco, Medicinal, and Special Crops, and Leonard W. Kephart, senior agronomist, Division of Cereal Crops and Diseases, Bureau of Plant Industry, Soils and Agricultural Engineering, Agricultural Research Administration

Contents

Page

A widespread menace to health 1 Forms of poison-ivy and poison-oak 2 Common poison-ivy 2 Oakleaf poison-ivy 9 Western poison-oak 9 Poison sumac 16 Confusion of poisonous and harmless sumacs 19 Introduced poisonous sumac and related species 21 Poisoning 21 Precautions against poisoning 22 Treatment for poisoning 23 Eradication of plants 25 Chemical weed killers 25 Eradication by mechanical means 25

A WIDESPREAD MENACE TO HEALTH

EVERY year sees many adults, and especially children, accidentally poisoned from contact with plants that they did not know were harmful. Had the sufferers known how to detect poisonous plants they could have avoided them and escaped the painful experience of severe skin inflammations and water blisters. Very few persons have a sufficient degree of immunity to protect them from poisonous plants, and many do not recognize them in the various forms that they assume in different parts of the country.

One or more kinds of poison-ivy--common poison-ivy, oakleaf poison-ivy, and western poison-oak--occur in abundance in almost every part of the United States. Poison sumac is of more limited distribution and occurs chiefly east of the Mississippi River, usually in swampy regions.

Poisoning by these plants is largely preventable. A knowledge sufficient to identify them in their various forms is easily gained by anyone who will make a study of pictures and general descriptions and train himself by a little diligent practice to observe the plants in his locality. It is important to become poison-oak or poison-ivy conscious. This can be accomplished only by learning to know the plants by repeated experience in observing them in their various forms. Persons who learn both to know and to avoid the plants can save themselves much inconvenience and discomfort. The simple means of learning to recognize them will pay big dividends. It is the first step to the prevention of poisoning and to the eradication of the pests from private grounds and public places.

The most effective method of prevention is to eradicate the plants, and wherever possible this should be done. They should not be allowed to grow in lawns or gardens, with ornamental shrubbery, or on houses. Communities should not countenance the growth of poison-ivy or poison-oak in school grounds, on public roadways, or in parks, especially those frequented by children. The cost of medical aid for one season in treating pupils using an ivy-infested schoolyard is likely to be more than that of eradicating the plants, to say nothing of the suffering and inconvenience they may cause.

FORMS OF POISON-IVY AND POISON-OAK

Poison-ivy and poison-oak are known by a number of local names, and several different kinds of plants are called by these names. The plants exhibit a good deal of variation throughout the United States, so much so that even technical botanists cannot agree on the number of species and names that should be applied to them. They grow in the form of (1) woody vines attached to trees or objects for support, (2) trailing shrubs mostly on the ground, or (3) erect woody shrubs entirely without support. They may flourish in the deep woods, where soil moisture is plentiful, or they may be found in very dry soil on the most exposed hillsides. The plants are most frequently abundant along old fence rows and edges of paths and roadways, and they ramble over rock walls and climb posts or trees to considerable heights. They often grow with other shrubs or vines in such ways as to escape notice.