The plant you ask about is Coleus forskohlii (also known as 'Plectranthus barbatus') in the family of plants called Lamiaceae. It actually grows wild in parts of West Bengal. The article referenced below, entitled "Development of Coleus forskohlii as a medicinal crop", from the Food and Agriculture Orgainization Document Repository, should give you much information of interest. The website is listed below:
www.fao.org

Here is an excerpt from the above web document:
Coleus forskohlii grows wild on sun-exposed arid and semi-arid hill slopes of the Himalayas from Simla eastward to Sikkim and Bhutan, Deccan Plateau, Eastern Ghats, Eastern Plateau and rainshadow regions of the Western Ghats in India. Latitudinal and altitudinal range for the occurrence of the species is between 8 degrees and 31 degrees N and 600-800 m respectively. The species was studied for its ecological preferences in its native habitats throughout its distribution range excluding Eastern Plateau, Sikkim and Bhutan. Before the botanical studies were undertaken, the species was studied in the regional floras and herbarium specimens were examined in seven zonal herbaria of the botanical survey of India at Dehra Dun (Himalayan flora), Allahabad (Central India flora), Shillong (northeastern India flora), Jodhpur (Rajasthan flora), Pune (western India flora), Coimbatore (southern India flora) and Port Blair (Andaman and Nicobar group of islands flora), as well as at the Forest Research Institute, Dehra Dun and the Blatter Herbarium in Bombay. Eleven representative ecogeographic areas were selected for habitat and population studies; between 1982 and 1985, 27 botanical trips were made for the purpose. Coleus-growing areas in the Himalayas in Uttar Pradesh were visited every month from April to December, and the other areas were visited at least twice during the blooming period. The following is the summary of the observations made on different populations and habitats of C. forskohlii (Shah 1989).
• C. forskohlii is a subtropical and warm temperate species naturally growing at 600-1800 m elevation
• The species grows on sun-exposed hill slopes and plateaus in arid and semi-arid climatic zones
• The species inhabits loamy or sandy-loam soil with 6.4 to 7.9 pH
• The species is herbaceous with annual stems and perennial rootstock

The market for the substance taken from this plant, a diterpene called forskolin, is large, judging from the number of results I got when I put "coleus forskohlii" into the search engine, Google. Most of them were to sites that offer herbal remedies, vitamins, that sort of thing. And the fact that the above-quoted and referenced article even exists, demonstrates that there is a market for the plant due to its derivative, forskolin.

New York University's Langone Medical Center has information about the plant's medicinal uses, as well as some words of caution about drug interactions (with anti-coagulants and anti-hypertensives). The medicinal uses of this plant have not been evaluated fully for safety. Sloan-Kettering Cancer Center also has useful information about Coleus forskohlii. Here is a brief excerpt: "Very limited data are available concerning the efficacy of forskolin. Most studies performed with forskolin have been human trials; those performed on heart failure and glaucoma are inconclusive."

Season All Season
Date 2006-10-17
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The ‘chat’ or ‘khat’ tree is Catha edulis (Celastrus edulis), and the leaves and branchlets have properties that stimulate the central nervous system. In addition to the euphoric or inebriating properties, chewing the leaves can cause irritability, decreased appetite, gastric upset, constipation, and inflammation of the mouth. Habitual use can lead to periodontal disease, and increased risk of esophageal cancer. The active compounds are Alkaloid D-norpseudoephedrine, as well as other alkaloids, and tannins. (Source: Medical Botany: Plants Affecting Human Health by Walter H. Lewis; John Wiley & Sons, 2003, 2nd ed.)

The Handbook of Medicinal Herbs by James A. Duke (CRC Press, 2002, 2nd ed.) indicates that Catha edulis has been used medicinally to treat a great number of ailments, including asthma, depression, diarrhea, glaucoma, and low blood pressure. Use of khat “is an ancient, socially acceptable tradition in the Afro-Arabian culture (and)…became known as a recreational drug in the USA after American soldiers were exposed to its use in Somalia. Khat is subject to legal restrictions in many countries.” (Medicinal Plants of the World by Ben-Erik van Wyk; Timber Press, 2004).

As for whether to report the harvesting of leaves from your tree, that would depend on whether khat use is specifically prohibited by law in Australia.

Season All Season
Date 2006-12-07
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I would suggest proceeding with extreme caution, and talking to your physician before endeavoring to make sassafras tea. According to Medical Botany: Plants Affecting Human Health by Walter Lewis (Wiley, 2003), the active component in Sassafras albidum, safrole, is no longer generally regarded as safe. It is toxic to the liver and can cause cancer. Here is information from British Columbia Cancer Agency and the U.S. Food and Drug Administration. This is an excerpt from the FDA site:
"Aromatic sassafras tea, once popular as a stimulant and blood thinner and as a reputed cure for rheumatism and syphilis, causes cancer in rats when taken in large amounts. Oil of sassafras and safrole, major chemical components of the aromatic oil in sassafras root bark, were taken out of root beer more than 30 years ago. And sassafras bark was banned from use in all food. Safrole-free extract, however, is allowed in food."

Although historical sources may discuss the best time to harvest parts of the Sassasfras plant for medicinal uses, I would recommend against using it for this purpose, given the associated health risks. Tyler's Honest Herbal by Steven Foster and Varro Tyler says that the root bark was used as a febrifuge prior to 1512 by native dwellers in Florida. The fact that its reputation for usefulness persists is mainly due to its pleasant aroma and flavor, but the authors make clear that it is unsafe.

You are welcome to come in to the Miller Library and explore our resources on medicinal plants and herbs, but I would not advise you to follow any recipes you might find there.

Season All Season
Date 2008-07-17
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