MICHIGAN ACADEMY OF SCIENCE. 171 



sively in making permanent mounts of objects for examination under the 

 miscroscope ; the hemlocli, the bark of which is extensively used in tanning; 

 the several spruces, which furnish a gum usefl chiefly in the manufacture of 

 chewing 'gum ; dogwood, witehhazel, black cherry, prickly ash, sassafras, 

 white oak, the barks of all being of medicinal interest. The list of herbaceous 

 plants, including golden seal, blood root, mandrake, wiutergreen, etc., is too 

 long to be included here, and would contain nearly all of the important official 

 articles collected in the United States.* 



The principal object of this article is to present a summary of last year's 

 experiments in the growing of medicinal plants at the University of Michigan 

 Botanical Gardens. These experiments, taken in conjunction with the rather 

 extensive farms already established in various parts of Southern Michigan, 

 seem to show that this state is destined to become one of the great drug- 

 pi'oducing states in this country. In manufacturing pharmacy, she holds first 

 place. Probably one-half of the medicines used in the United States are the 

 output of the manufacturing laboratories located in Detroit alone. At the 

 present time there is a greater acreage in Michigan devoted to the cultivation 

 of medicinal plants than in any other state. Tlie story of the peppermint 

 industry in Michigan affords one of the most interesting chapters in the devel- 

 opment of our natural resources. By the application of industry and the 

 ability to form rational conclusions, followed by simple field experiments, the 

 mint industry has been developed, adding wealth and honor to the pioneer 

 and enriching those who were willing to duplicate his experiments. 



The interest in the cultivation of medicinal and economic plants began 

 with the early settlers. Hops may be considered the first medicinal plant 

 to be grown in the United States. It was first grown in Virginia, but with 

 very poor success. Later it was found that a colder climate was better suited 

 for the growth of the hop plant and the cultivation was taken up by some 

 of the farmers in New England. It was then introduced into New York state 

 and later into Michigan, and some of the other middle and western states. 

 It is from these states that our commercial supplies are chiefly obtained. 



It is not always easy to determine what plants can be successfully grown 

 in any given locality. Only actual field tests can give the correct' data. 

 Failure, while it has a practical significance, acts only as a stimulas to the 

 pioneer. There are indeed very few plants that have not become established 



*The following? are some of the works dealing with the Flora of Michigan, all of 



which are in the I^ihrary of the University. 



Beal, W. J. Michigan Flora. Published by the Michigan State Agricultural Col- 

 lege, 1S'.I2. 



Beal, W. J. Michigan Flora, a list of the fern and seed plants growing without 

 cultivation. I'ublislied by the State Board of Agriculture, Agricultural 

 College, Michigan, 1904. • 



Farweil, O. A. A catalog of tlie flora of Detroit. Reprinted from the second annual 

 report of the Michigan Academy of Science. 



Otis, Charles II. Michigan trees. ' University Bulletin, v. 14, No. 16, 101.3. 



Transeau, E. II. The bogs aiul the bog flora of the Huron River valley. Reprint 

 Botanical CJazrttr 40: .■?.51-."'.7r), 418,448, 1905, and 41: 17-42, 1906. 



Wheeler, Charles E'. and Smith, E. F. A catalog of the Phaenogainous and vascular 

 Cryptoganio\is plants of Michigan, 



