The branches are very rough, the leaves long, unequally toothed, rough with hairs on both sides, the leaf-buds covered with a dense yellow Wool. The flowers are stalkless.

The inner bark has important medicinal value and is an official drug of the United States Pharmacopoeia.

The bark, which is the only part used, is collected in spring from the bole and larger branches and dried. Large quantities are collected, especially in the lower part of the state of Michigan. As the wood has no commercial value, the tree is fully stripped and consequently dies.

The bark as it appears in commerce for use in medicine consists only of the inner bark or bast and is sold in flat pieces 2 to 3 feet long and several inches wide, but only about 1/8 to 1/16 of an inch in thickness. It is very tough and flexible, of a fine fibrous texture, finely striated longitudinally on both surfaces, the outer surface reddish-yellow, with patches of reddish brown, which are part of the outer bark adhering to the inner bast. It has an odour like Fenugreek and a very mucilaginous, insipid taste. The strips can be bent double without breaking: if broken, the rough fracture is mealy, strongly but finely fibrous. The clean transverse section shows numerous medullary rays and altemate bands of bast parenchyma, thus giving it a chequered appearance. A section moistened and left for a few minutes, and again examined, shows large swollen mucilage cells.

The powdered bark is sold in two forms: a coarse powder for use as poultices and a fine powder for making a mucilaginous drink. The disintegrated bark forms, when moistened, a flexible and spongy tissue, which is easily moulded into pessaries, teats, and suppositories.

It is recommended that ten-year-old bark should be used.

The powder should be greyish or fawncoloured. If dark or reddish, good results will not be obtained. The powdered bark is said to be often adulterated with damaged flour and other starchy substances.

---Constituents---The principal constituent of the bark is the mucilage contained in large cells in the bast. This mucilage is very similar to that found in linseed. It is precipitated by solutions of acetate and subacetate of lead, although not by alcohol The mucilage does not dissolve, but only swells in water and is so abundant that 10 grains of the powdered bark will make a thick jelly with an ounce of water.

Microscopic examination of the tissue of the bark shows round starch grains and very characteristic twin crystals of Calcium oxalate.

---Medicinal Action and Uses---Demulcent, emollient, expectorant, diuretic, nutritive. The bark of this American Elm, though not in this country as in the United States an official drug, is considered one of the most valuable remedies in herbal practice, the abundant mucilage it contains having wonderfully strengthening and healing qualities.

It not only has a most soothing and healing action on all the parts it comes in contact with, but in addition possesses as much nutrition as is contained in oatmeal, and when made into gruel forms a wholesome and sustaining food for infants and invalids. It forms the basis of many patent foods.

Slippery Elm Food is generally made by mixing a teaspoonful of the powder into a thin and perfectly smooth paste with cold water and then pouring on a pint of boiling water, steadily stirring meanwhile. It can, if desired, be flavoured with cinnamon, nutmeg or lemon rind.

This makes an excellent drink in cases of irritation of the mucous membrane of the stomach and intestines, and taken at night will induce sleep.

Another mode of preparation is to beat up an egg with a teaspoonful of the powdered bark, pouring boiling milk over it and sweetening it.

Taken unsweetened, three times a day, Elm Food gives excellent results in gastritis, gastric catarrh, mucous colitis and enteritis, being tolerated by the stomach when all other foods fail, and is of great value in bronchitis, bleeding from the lungs and consumption (being most healing to the lungs), soothing a cough and building up and preventing wasting.

A Slippery Elm compound excellent for coughs is made as follows: Cut obliquely one or more ounces of bark into pieces about the thickness of a match; add a pinch of Cayenne flavour with a slice of lemon and sweeten, infusing the whole in a pint of boiling water and letting it stand for 25 minutes. Take this frequently in small doses: for a consumptive patient, about a pint a day is recommended. It is considered one of the best remedies that can be given as it combines both demulcent and stimulating properties. Being mucilaginous, it rolls up the mucous material so troublesome to the patient and passes it down through the intestines.

In typhoid fever, the Slippery Elm drink, prepared as for coughs, is recommended, serving a threefold purpose, to cleanse, heal and strengthen, the patient being allowed to drink as much as desired until thirst has abated, and other remedies can be used. If the patient is not thirsty, a dose of 2 large tablespoonfuls every hour for an adult has been prescribed.

The bark is an ingredient in various lung medicines. A valuable remedy for Bronchitis and all diseases of the throat and lungs is compounded as follows: 1 teaspoonful Flax seed, 1 OZ. Slippery Elm bark, 1 OZ. Thoroughwort, 1 stick Liquorice, 1 quart water. Simmer slowly for 20 minutes. Strain and add 1 pint of the best vinegar and 1/2 pint of sugar. When cold, bottle. Dose: 1 tablespoonful two or three times a day.

In Pleurisy, the following is also recommended: Take 2 oz. each of Pleurisy root, Marsh Mallow root, Liquorice root and Slippery Elm bark. Boil in 3 pints of water down to 3 gills. Dose: 1/2 teaspoonful every half-hour, to be taken warm.

As a heart remedy, a pint of Slippery Elm drink has been prescribed alternately with Bugleweed compound.

Slippery Elm bark possesses also great influence upon diseases of the female organs.

It is particularly valuable both medicinally and as an injection in dysentery and other diseases of the bowels, cystitis and irritation of the urinary tract. The injection for inflammation of the bowels is made from an infusion of 1 OZ. of the powder to 1 pint of boiling water, strained and used lukewarm. Other remedies should be given at the same time.

An injection for diarrhoea may also be made as follows: 1 drachm powdered Slippery Elm bark, 3 drachms powdered Bayberry, 1 drachm powdered Scullcap.

Pour on 1/2 pint of boiling water, infuse for half an hour, strain, add a teaspoonful of tincture of myrrh and use lukewarm.

As an enema for constipation, 2 drachms of Slippery Elm bark are mixed well with 1 OZ. of sugar, then 1/2 pint of warm milk and water and an ounce of Olive Oil are gently stirred in.

Injection for worms (Ascarides): 1/2 drachm Aloes powder, 1 drachm common salt, 1/2 drachm Slippery Elm powder (fine). When well mixed, add 1/2 pint warm water and sweeten with molasses, stirring well.

Slippery Elm mucilage is also prescribed to be mixed with Oil of Male Fern (2 oz. of the mucilage to 1 drachm of the oil) as a remedy for the expulsion of tapeworm

The Red Indians have long used this viscous inner bark to prepare a healing salve, and in herbal medicine a Slippery Elm bark powder is considered one of the best possible poultices for wounds, boils, ulcers, burns and all inflamed surfaces, soothing, healing and reducing pain and inflammation.

It is made as follows: Mix the powder with hot water to form the required consistency, spread smoothly upon soft cotton cloth and apply over the parts affected. It is unfailing in cases of suppurations, abscesses, wounds of all kinds, congestion, eruptions, swollen glands, etc. In simple inflammation, it may be applied directly over the part affected; to abscesses and old wounds, it should be placed between cloths. If applied to parts of the body where there is hair, the face of the poultice should be smeared with olive oil before applying.

In old gangrenous wounds, an excellent antiseptic poultice is prepared by mixing with warm water or an infusion of Wormwood, equal parts of Slippery Elm powder and very fine charcoal and applying immediately over the part.

A very valuable poultice in cases where it is desirable to hasten suppuration or arrest the tendency to gangrene is made by mixing the Slippery Elm powder with brewer's yeast and new milk.

Compound Bran poultice is made by mixing with hot vinegar equal quantities of wheaten Bran with Slippery Elm powder. This is an excellent poultice for severe rheumatic and gouty affections, particularly of the joints, synovitis etc.

Herbal poultices, generally made from the bruised, fresh leaves of special herbs, are frequently mixed with Slippery Elm and boiling water sufficient to give the mass consistency.

Marshmallow Ointment, one of the principal ointments used in herbal medicine, has a considerable proportion of Slippery Elm bark in its composition. It is made as follows: 3 oz. Marshmallow leaves, 2 OZ. Slippery Elm bark powder, 3 oz. Beeswax, 16 OZ. Lard. Boil the Marshmallow and Slippery Elm bark in 3 pints of water for 15 minutes. Express, strain and reduce the liquor to half a pint. Melt together the lard and wax by gentle heat, then add the extract while still warm, shake constantly till all are thoroughly incorporated and store in a cool place.

The bark of Slippery Elm is stated to preserve fatty substances from becoming rancid.

It has been asserted that a pinch of the Slippery Elm powder put into a hollow tooth stops the ache and greatly delays decay, if used as soon as there is any sign of decay.

Lozenges or troches containing 3 grains of Elm flavoured with methyl salicylate are used as a demulcent.

---Preparations---Mucilage, U.S.P., made by digesting 6 grams of bruised Slippery Elm in 100 c.c. and heated in a closed vessel in a water-bath for 1 hour and then strained.

---Other Species---
Fremontia Californica, or Californian Slippery Elm, has bark with similar properties, and is used in the same way, but is not botanically related.