20 BULLETIN" 683, U. S. DEPARTMENT OF AGEICULTUEE. 
The estimate for slippery elm is 12 per cent, used mostly in Illinois 
and Indiana. Small amounts of cork elm are used in several northern 
States and a small amount of wing elm in Texas. Reports from 
manufacturers included under this head give an average cost of $18.63 
at the factory for elm. This is a low price compared to the prices paid 
for elm by other industries, and is due to its being obtained largely 
in the log and also to the utilization of low-grade material. 
VEHICLES. 
Elm is an important vehicle wood, an annual use of more than 
31,000,000 board feet being reported. Michigan, Ohio, and Wisconsin 
lead in its consumption for vehicles and vehicle stock, the amount re- 
ported for these States being as follows: Michigan, 7,813,000; Ohio, 
7,285,000; Wisconsin, 6,657,000. The total for the three States is 
nearly 70 per cent that of the entire United States. Iowa, Arkansas, 
Indiana, and Minnesota are next in order, consuming amounts be- 
tween approximately one and two million board feet. 
About two-thirds of the total was reported as white or gray elm or 
simply as "elm," and about one-third as cork and rock elm, and a 
very small per cent as slippery elm. White elm is chiefly valuable 
for the frames of bodies and tops of vehicles. Cork elm is used for 
singletrees and eveners, and for parts of the running gear, such as 
reaches and hounds, especially of light vehicles, and for the bows on 
which the top is stretched. 
There has always been a good demand for rock elm for wagon and 
carriage hubs because of its hardness and ability to stand shock. 
The hub is bored out and is either completely covered by steel bands 
or a band sunk into it on each side to prevent checking. On account 
of the growing popularity of the automobile, which has all metal 
hubs, the demand for this material is now comparatively small. 
Some large wheel manufacturers have a sufficient supply of elm hub 
material to last for several years. 
In 1911 Michigan manufacturers reported an annual consumption 
of 842,000 feet for automobiles. Since then there has been a con- 
siderable increase in the quantity used for automobiles, and probably 
a decrease in the quantity for horse-drawn vehicles. 
Both the white and cork elm are used by automobile body makers. 
The cork or "rock" elm is used for corner blocks in the framework 
because of its strength and its ability to withstand shock and to hold 
screws. Large quantities of white and slippery elm go into the frame- 
work, chiefly in bent pieces. The more porous elm (often called 
swamp and water elm) is preferred, since it is said not to break so 
readily in bending. The wood is received at the factory in the green 
condition, is steamed, then bent to the desired form, held in shape, 
and kiln dried. Even when great care is exercised to select proper 
