Slippery elm bark.

Botanical name: 

From: "linda greene"
Subject: [Herb] (slippery elm)
Date: Sat, 18 Jan 2003 22:22:16 -0500

I have heard/read mixed information on slippery elm. One herbalist told me the elm tree in endangered; information I received in pharmacy school all state that slippery elm is dangerous or toxic even; and a local pharmacy that compounds herbal products exclusively sells tons of it and the pharmacist there seemed to think it was basically a safe herb. I am preparing a lecture on the safe use of herbs, so any comments on slippery elm would be greatly appreciated. Thanks, Linda Greene, Pharm D.

From: Henriette Kress

Elm trees in North America have been severely decimated by Dutch Elm Disease; this includes slippery elm, Ulmus fulva. You use the bark of the tree. Now, how do you get the bark? You either cut off branches or you cut down the tree. You get more bark from larger trees, but your larger trees are decades if not centuries old. How long does it take to get new trees to replace the ones you've just cut down?

Other species of Ulmus give equally good inner bark, but they're not generally used. Yes, anybody who sells elm bark by the ton is decimating the stands. I don't even know if it's cultivated - but cultivation would require extreme long-term tree farms.

There are tree farms, but they're usually for trees where you use the leaf (ginkgo, chinese tea, and the like) or the fruit (nuts, oranges, apples, and similar). I know of none where you'd use the bark; bark from cultivated trees would probably be rather too expensive.

So use crushed linseed, if you need the mucilage. Or use mallow species - any of them will do. Or psyllium seed.

Also note, if you buy slippery elm in powder, it's generally adulterated with other, cheaper powders. Like starches and such. Which of course makes it easier to sell tons of the stuff, no?

Update 2015: "I just wanted to bring to your attention that Botanical Plantations is a group of Certified Organic Farms supplying Cultivated Organic slippery Elm Bark."
I'm sure there are other suppliers as well, these days.

From: Joyce Wardwell

>...Use the bark of the tree. Now, how do you get the bark? You either cut off branches or you cut down the tree.

In the long run, it is best not to cut branches off living trees. Too often unsanitary pruning practices are used introducing disease through the open wound. Go back to the tree 5 to 10 years later and you will often see fungal, parasitical or viral illness manisfestations on the tree you so "gently just took a couple of branches."

>You get more bark from larger trees, but your larger trees are >decades if not centuries old.

In the case of slippery elm, you may get more, but it is decidely more difficult to peel the inner bark as the tree gets older. Now older slippery elm outer bark is useful for wigwam covering... so you can harvest and use both inner and outer bark.... but unless you are living primitively, it really isn't needed.

Best way to harvest bark medicinally is to find a cluster of thumb to wrist size saplings. Pick the saplings that are too crowded, bent or not receiving enough sunlight. In mid-spring, cut down take out these saplings. Take no more than YOUR FAMILY will use. Make your cut angled 45 degrees as saplings stands often share rootstock, and the angle cut will help the stump remains shed water. This will leave a healthier stand, and be the easiest bark to peel.

The general rule of thumb for optimal growth IN A WOODLOT is to leave 4-5' diameter spacing between saplings, 8-10 feet diameter once the tree is larger than 6" diameter, 12-15 feet for mature trees.

Dutch elm disease has pretty much wiped out the American Elm. I have seen in Southern Ohio it start to attack slippery elm now that the American elms are gone. Here in northern Michigan, becasue we are a peninsula, the disease is just starting to attack the American elms. But I imagine in 25 years or so, the slippery elms will be next. So for long term use, we will HAVE to find substitutes.

Slippery elm is probably one of the least toxic herbs out there. Since toxicity is largely a question of dose, I suppose if I drank about 7 liters of slippery elm tea at once, my stomach might burst from all the liquid.....