UTILIZATION OF BLACK WALNUT. 23 
to the year 1915. During the years 1915 and 1916 there was an 
increase of about 50 per cent over previous years. In 1917 there was 
a falling off in production. In 1918 there was an increase to 100 
million board feet as a result of war demands. Missouri shows a 
marked increase in production, and Iowa a large output since 1914, 
because the large mills in these States obtained new supplies from a 
great part of the walnut region west of the Mississippi. The States 
of Kentucky and Tennessee have kept up a fairly steady cut of 
walnut lumber. Ohio, Indiana, and Illinois also have steadily fur- 
nished very large amounts from the beginning of the walnut-lumber 
industry. 
