20 BULLETIN 229, TJ. S. DEPARTMENT OF AGRICULTURE. 
will be 12 inches from the ground (Plate III, fig. 2). In Plate IV, 
figure 1, the first streak is 17 inches higher than necessary. On the 
basis of one-b-alf inch streaks this means that a height sufficient for 
34 clappings, or for a whole season, has been lost. 
Class 2. (Plates V and VI.) The gum flowing from the face is 
guided into the cup by means of a flat oblong piece of galvanized 
iron, with the ends slightly upturned, called an " apron." The edge 
of the apron to be inserted in the tree is concave to conform to the 
tree's shape. In some cases the aprons are made in two pieces, 
riveted together at the ends, so as to allow them to be adjusted to 
the curvature of each particular tree. They are also made in two 
separate pieces. The aprons are inserted in a horizontal gash at the 
base of the tree made with a broadax having a flat blade with a 
concave edge. When inserting the apron a small blaze about 6 
inches wide and 2 inches high is generally made to remove objection- 
able bark. The broadax is held horizontally against the blaze, 
with the head slightly downward, by one man,, while another drives 
it into the tree with a maul. . The ax is then withdrawn and the 
apron inserted. 
A recently introduced apron is lunar in shape, the concave edge 
being provided with stiff teeth. This apron can be driven directly 
into the tree, obviating the necessity of blazes or gashes. 
The cups are made of galvanized iron or clay and hold about a 
quart. Their general shape is that of an oblong box 12 inches by 3 
inches at the top, and about 3 inches deep. They are slightly larger 
at the top than at the bottom, and are sometimes shaped to con- 
form to some extent to the curvature of the tree. The cups are 
sometimes hung from the apron by means of small hooks which 
engage an extension on either end of the apron, or they may be 
supported on a nail driven into the tree beneath the apron. The 
likelihood of the fasteners becoming clogged by gum is obviated by 
the use of nails as supports. In hanging this class of cups large 
blazes are not necessary, and if properly hung practically all the 
gum flowing from the tree reaches the cups. As the aprons occupy 
but little vertical space and the cups are comparatively shallow, a 
distance of 12 inches from the ground to the first streak is ample on 
normal trees (Plate V, fig. 1). In the case of small trees 10 inches 
or less in diameter, the use of the 2-piece or riveted apron allows a 
shallower cut to be made in hanging the cup, as the 1-piece aprons 
have such a large curvature that they require a deep cut in small 
trees (Plate VI, fig. 1) to prevent escape of gum at the sides. On 
large timber, of course, this difficulty does not occur. 
Class 3. (Plate VII, fig. 1.) The cup is so constructed as to obviate 
the necessity of using a gutter or apron. In order to hang it, several 
