Excerpts: Sumac, known to the public in the United States chiefly as a vigorous beautifier of roadsides and wastelands, contains much tannin in its leaves and leaf stems. Tannin extracted from the leafage of this shrub or small tree is regularly used by tanners in this country in producing certain types of leather. For almost a century several of our native sumac species have been recognized as a plentiful source of this substance essential to the tanning and dyeing industries. Nevertheless United States industries, thus far, have used only very small quantities of native sumac material as a source of tannin; they get the sumac tannin they need mainly by importing, from Sicily, leaf material of the sumac species Rhus coriaria. Interest in our native sumacs as a source of tannin has increased from time to time as domestic supplies of the vegetable tanning materials commonly used in the United States have gradually declined. Improvement in the quality of the domestic harvested product would certainly increase the demand for it. Sumac can flourish under a great variety of environmental conditions, and it grows naturally in almost all parts of the eastern half of the United States. Efforts to grow the commercially used native species as a farm crop have sometimes been suggested, particularly when the supply of American chestnut wood was beginning to dwindle as a result of the chestnut blight epidemic and when world conditions have threatened to interfere with importing tanning material from other countries. For these reasons, the Agricultural Research Service has made a study of the propagation and management of sumac as a crop to be grown on farms in order to supplement income from principal crops. The study dealt with the native species that have been utilized to some extent in this country for tannin production. This report discusses the utilization of wild sumac for tannin production in the United States and presents the results of the study of sumac as a cultivated.
