MEDICINAL PLANTS AND EXOTIC MUSHROOMS
Dr. Deborah B. Hill
Professor and Forestry Extension Specialist
University of Kentucky
Lexington, KY 40536-0073
Introduction:
Much of the midsouthern part of the United States, including Kentucky and Tennessee, is blessed with an abundance of forest land. Much of this land is rolling or hilly topography, especially in the eastern parts. The species mixture is varied and predominantly hardwoods. Traditional forest products of sawtimber and pulpwood have been harvested on these lands for more than a hundred years, and some mismanagement in the history of both states has resulted in large acreages of less than premium quality timber. Another common denominator between the two states is large numbers of small private ownerships. There is little industrial or corporate ownership in Kentucky, and Tennessee is likely to be similar. Both states have public forest lands in their National Forests - the Daniel Boone in Kentucky and the Cherokee in Tennessee. Well more than three-quarters of the merchantable timber in both states is owned by individuals. In Kentucky, we have probably close to a half million owners, but the average woodland ownership is 25 acres and about 60% of those owners own even smaller woodlots, more like 10 acres. What this means in terms of forest management is that “business as usual”, meaning timber harvesting, may not be feasible either economically or ecologically for these owners. It is important then for such owners to look to their forest lands as an opportunity for some short term, non-timber forest products to give their farm economy supplemental income. This conference is one attempt to expose farm and forest landowners to a variety of options that they might consider for that purpose.
Income opportunities vary from agritourism or bed and breakfast, to apiculture (bees and hive products), to aquaculture (catfish, paddlefish and shrimp), to Christmas trees and floral greens, to crafts materials of every description, to fenceposts and fuelwood, to native fruits and nuts (e.g., pawpaw and persimmon, walnut and hazelnut), to game preserves and lease hunting, to high value timber such as paulownia and walnut, to maple syrup, to medicinal plants and mushrooms usable for culinary or medicinal purposes. This presentation will focus on medicinal plants and exotic mushrooms.
Medicinal Plants:
The medicinal plant that is best known and which has the highest economic value is American ginseng (Panax quinquefolium L.). It has been used for millenia as a general blood tonic and the active ingredient, ginsenoside, appears to boost the immune system and oxygenate the blood. The plant grows naturally in this area - the distribution map covers much of the United States east of the Mississippi River - and Kentucky and Tennessee are right in the middle of the natural range. American ginseng is a forest floor plant which makes a single palmately compound leaf (that means the spread of the leaflets looks like your hand with the fingers extended). Very young plants will have only one or two of these leaves (also called “prongs”); older plants will have up to five. Regardless of the age of the plant, it does not seem to form more than five leaves. One unusual thing about its life cycle is that it takes 18 months for the seed to germinate - it apparently needs to go through two cold cycles before it is ready to put up a leaf. It is the root of the plant that is valuable, and ginseng naturally forms a taproot like a carrot or parsnip. It takes a minimum of five years to produce a marketable root, and the longer the root grows, and the more peculiar its shape, the more valuable it becomes. A serious problem with ginseng is vandalism. It happens only too frequently that someone is growing a patch of ginseng in the woods and has waited patiently until the roots should be old enough to harvest, and then found them removed by someone else before the owner has a chance to do so. Since much ginseng is grown from seed (it can also be grown from 1- or 2-year rootlets), the seed balls that are formed - usually after the third year - are another potential source of income. Seeds are usually ripe in late summer or early fall and change color from green to red. The roots should not be harvested (when they are old enough!) until after the seeds have ripened. Woods grown or wild-simulated grown ginseng (if you can hold onto it!) is worth at least $300 per pound dried root. Ginseng can be grown like any other shade-grown crop on raised beds under shade cloth, but it has a very low value - more like $20 per pound. The ginseng market is now both national and international, and brokers are available both in state and in other parts of the U.S. Because the vandalism problem is so serious, it is important to work with local officials to see that the existing laws that protect woods grown ginseng from overharvesting and from vandalism are strictly enforced.
Probably the second most familiar woods grown medicinal plant is goldenseal (Hydrastis
canadensis L.). This, too, has a long history of use in this country. It was used by Native Americans for eye afflictions, and is also used as an immune system booster. If you look around in markets today, you will find readily available bottles of medicinal plants such as Echinacea and Goldenseal for colds and flu symptoms. Goldenseal is also a forest floor plant and often grows in the same areas as ginseng naturally. They can therefore be grown together intentionally. Goldenseal varies from ginseng in that the marketable root, which is a fibrous root rather than a taproot, will form within three years. Also, both the root and the leaves are marketable. Goldenseal forms one leaf per stem as does ginseng, but it is a simple leaf with fairly deep-cut lobes, not separate leaflets. Goldenseal will have two or three leaves on a single plant, each coming directly from the soil. Goldenseal can be grown from seed (it also forms a seed ball like ginseng, but it is much smaller), but is often propagated from the bud of new growth that occurs at the base of the leaf stem. Goldenseal also can be grown repeatedly in the same area, whereas ginseng usually cannot. The market for goldenseal is about $30-50 per pound dried root.
There are many other common forest floor or forest-based medicinals. Both black cohosh (Cimicifuga racemosa Nutt.) and blue cohosh (Caulophyllum thalictroides Michx.) are in increasing demand for the treatment of gynecological problems, and bloodroot (Sanguinaria canadensis L.) and wild ginger (Asarum canadense L.) are also marketable. Other medicinals such as witch hazel (Hamamelis virginiana L.) and slippery elm (Ulmus rubra L.) bark are also marketable. Medicinal plant brokers are scattered all over the U.S. They will help you with details like what time of year to harvest, what part or parts of the plant they want, how to dry them correctly and how to package them for shipment.
Mushrooms:
There are several types of edible and/or medicinal mushrooms that either grow on wood (i.e., logs) or on the forest floor. My extension program in Kentucky focuses on the production of shiitake (Lentinula edodes L.) mushrooms because they are becoming the best known of the exotic mushrooms, but there are several others to consider.
Shiitake are brown-capped, white stemmed mushrooms native to Japan and have been cultivated in the Orient for centuries. Mushroom strains and spawn began to be produced in the United States during the 1970s. They grow on virtually any variety of hardwood log native to the United States, although some species of trees are more productive than others. Shiitake have become close to a mainstream product, as they can be found in many major supermarkets on a regular basis. Shiitake is now primarily either imported from the Orient in a dried form, or distributed from growers who are producing them on artificial substrate blocks rather than on natural hardwood logs. There is a quality and shelf-life difference between the two, and mushrooms from natural logs are considered to be superior in all respects. Shiitake, under proper management, can be expected to flush several times during the growing season in the open. It is also possible to manage the logs under cover over the winter.
Maitake (Grifola frondosa L.), also called “hen-of-the-woods”, is native to the hardwood forests of the United States and will grow both on the forest floor - usually at the base of a tree - or inoculated on logs. Both shiitake and maitake mushrooms have medicinal value as well as being delicious culinary mushrooms. Maitake grows in a series of shelf or fan-like forms rather than the classic stipe (stem) and parasol (top) shape common to shiitake and button mushrooms (Agaricus spp. L.). These fans are largely brown with white markings near the edges. Medicinal effects are at least as an immune system booster, can assist with heart/blood ailments and are antiviral. Maitake usually fruit in the fall.
Oyster mushrooms (Pleurotus spp.) are also native and come in a variety of shapes, sizes and colors. They are probably the best known “other” mushroom to buttons and Portabellas (also Agaricus spp.) and shiitake in the marketplace. They are commonly used, as are shiitake, in Oriental cooking. They, too, can be grown on logs or on other types of high cellulose substrates, and can be managed to fruit or flush on a regular basis during the growing season or year-round under cover.
Morels (Morchella spp. L.), also called “dry land fish”, are also native to the United States and extremely desirable for their culinary taste as well as for their economic value. Although the life cycle of these mushrooms is known, there are a couple of details that no one seems to have quite figured out. It is known by morel hunters that the same areas yield morels frequently, if not annually, but it is very difficult to start a morel bed from scratch. This is a mushroom that grows on the forest floor, and can be persuaded to grow in a sawdust mixture on the forest floor. However, all suppliers who sell kits to do this make no guarantees of success because it is such an iffy venture. Morels are common near old apple orchards and near elm trees. They fruit in the late spring and are so distinctive in appearance with their cone-shaped tops and their deeply pitted or sponge-like surface, it is difficult to confuse them with any other type of mushroom. The most frequently found varieties of morels are either dark brown, golden, or creamy colored on top with usually white or creamy stems.
King Stropharia (Stropharia rugosa-annulata L.) is another native mushroom. These ruby red-topped, white stemmed mushrooms can grow to truly giant size (tops measured a foot or more across), but are usually harvested at a smaller size for culinary use (tops more like a few inches across). Stropharia has an unusual talent - it is considered one of the organisms that can be used for bioremediation. If you have an area with water seepage and are concerned about the quality of that water - possibly near a spring - you can grow Stropharia on sawdust on the wet ground and the mushrooms will remove a variety of toxins. Of course, you would not want to use those mushrooms for eating, but if you are growing them elsewhere for food, some of the spawn you use to start your culinary bed may also be used to do a bit of environmental cleanup. Because they can grow to such a large size, I think this was probably the kind of mushroom Lewis Carroll had in mind when he had the caterpillar conversing from a mushroom top with Alice in Wonderland!
Lion’s mane (Hericium spp. L.) are yet another native mushroom. This is a type of fungus that can be found growing on living trees in our forests. It is a large (6"+ across)whitish or creamy mass with many small finger-like projections that point downward, thus giving it the appearance of a “mane” of hair. It is also called pompom or bearded tooth because of its appearance. It is slow growing and probably will produce only a single mass per log or substrate. It can be chopped and sauteed like other mushrooms or shredded into soups or stews as a thickener.
Reishi (Ganoderma lucidum L.) is edible, but is most often used for its medicinal value. Unlike most of the other mushrooms, it forms an often shiny (shellac-look) kidney-shaped top of dark red or mahogany brown. Depending on the light and moisture conditions under which it is grown, it can also take an “antlered” form. It can grow on logs or on sterilized substrates. The Orientals consider it to be the “elixir of life” and its medicinal properties are excellent. Because of its smooth and shiny exterior, it dries easily and stores well and can be ground up for teas or other
uses. Like shiitake, it requires freshly-cut living trees to colonize and will be ready to fruit in 4-6 months. It can be kept in production throughout the growing season.
Shiitake Mushroom Production:
Shiitake spawn, the active ingredient, comes in three forms: sawdust spawn, dowel spawn, and thimble spawn. Sawdust spawn is recommended because it usually is less expensive per unit or per log inoculated, gives a more thorough and faster “spawn run”, and is easy to use. The dowel spawn is the next most common and is very easy to use, as you just pound the dowels into the drilled holes with a hammer, but there is a smaller surface area to attach to the walls of the drilled holes. Thimble spawn is a recent addition from the spawn suppliers. It is pressed sawdust in the shape of a thimble and has a styrofoam plug attached to the top, so it is considered a “waxless” type of spawn. This cuts out a whole step in the inoculation process, and so can save considerable time. It is awkward to store, however, and must be used quickly upon receipt so that it doesn’t dry out. For most people, especially if you plan to inoculate many logs, it will not be worth the extra handling requirements and expense.