60 ANNUAL REPORTS OF DEPARTMENT OF AGRICULTURE. 



much disagreement aiiioug hop experts as to what constitutes the 

 fundamental basis of quahty. A study of certain constituents, 

 especially of volatile oils, resins, and acids, is designed to throw light 

 on this important question. 



"Work on tanning crops has been continued on a small experimental 

 basis, test plats of })romising plants being grown in different testing 

 gardens of the Department. The commercial and agricultural require- 

 ments that must be met in order to bring success are many and rather 

 exacting. 



The tea work has been continued in South Carolina. Last season's 

 outcome was very satisfactory from the standpoint of production and 

 quality, and the increasing demand for limerican tea quickly absorbed 

 the crop. More tea was sold in the Southern States than heretofore. 

 Work on the prmiing machine after many trials seems to have resulted 

 in a practical means of eliminating a large item of expensive hand 

 labor. Prmiing, heretofore costing about S2.25 per acre, can now be 

 done equally well at 50 cents an acre. 



Perfumery-plant and volatile-oil investigations have shown that 

 many of the foreign plants used for purposes of volatile-oil production 

 can be grown and distilled satisfactorily in this country. A study of 

 the native oil-bearing plants has developed the fact that among them 

 are several species yielding oils containing constituents which make 

 the foreign oils now imported commercially insignificant. For exam- 

 ple, the native horse mints and their near relatives, growing luxuri- 

 antly on waste lands, yield oils rich in thymol, a valuable and much- 

 used antiseptic now derived from foreign sources. Certain of the 

 sagebushes of the arid plains of the West yield oils rich in substances 

 now in demand. Native plants are well worthy of further study in 

 this direction. 



It sometimes happens that crude drugs come on the market in a 

 more or less mixed condition, a situation at times not detected by the 

 manufacturer or pharmacist using them; consequently, confusion as 

 to the facts concerning crude drugs of native origin at times creeps in. 

 Some time since the drug known as pinkroot was investigated by the 

 Department, and the true status of the situation made clear. During 

 the past year the same thing has been done with the wild-yam root, 

 the true and the false types having been distinguished and the botan- 

 ical sources of each ascertained. 



POISONOUS-PLANT INVESTIGATIONS. 



The field work on poisonous plants during the past year has con- 

 sisted of two types: (1) Feeding experimentation, carried on at a. 

 temporary station located at Mount Carbon, Colo., and (2) recon- 

 naissance work, carried on wherever complaints of considerable losses 

 have seemed to demand attention. At Momit Carbon the harmful 



