LIFE HISTORY AND CONTROL OF HOP FLEA-BEETLE. 49 
middle of the board and braced by an upright to the rear edge forms 
a handle. The canvas was then coated with tar; hence the name 
" tarred board." 
During the first part of the season a tarred board was placed on 
each side of a vine and the beetles jarred off with a bunch of grass. 
This was slow work, and it was found by actual count that 85 per 
cent of the beetles that were on the vines could be captured by placing 
a single board on the leeward side of a vine. The beetles are thrown 
onto it with a single sweep of a large brush (PI. IV, fig 1). This 
method reduces the cost of going over the field one-half, and twice 
the acreage can be relieved in the same length of time. 
Although effective as a flea-beetle catcher, this tarred board is a 
heavy and awkward thing to handle. A light shield which promises 
to be as efficient as the heavy tarred board is made of light galvanized 
iron, 3 feet wide and 2 feet high, the top of the iron being tacked 
around a curved board to hold it in shape. A piece of screen wire is 
fastened on the inside to prevent the oil from running down, and to 
make it fit close around the base of the vine a curved notch is cut in 
the bottom. The shield is operated by means of a hose-covered wire 
handle which is attached between the center of the iron and the mid- 
dle of the top board. 
The handle is held in the left hand, and, steadying the shield with 
the right, the notch is placed close to the base of the vine. Then, 
holding the shield at an angle of about 45°, the beetles are brushed 
onto the screen with a large feather duster (PL IV, fig. 2). 
Brushes. — During the first of the season many sorts of brushes were 
tried. Leafy birch twigs made a very effective brush, but did not last 
long; grass was not rigid enough, and broom straw was too stiff. 
The best green brush was made of young fir or cedar boughs. These 
form a screen as well as a brush and last all day. Cutting twigs and 
making brushes, however, becomes expensive, so that a large feather 
duster proves to be cheapest in the end. 
TARRED SLEDGES. 
When the second generation of beetles appeared in 1908, tarred 
sledges 8 feet long and wide enough to fill the spaces between rows 
were used to advantage. Eight or 10 of these sledges drawn by 
horses were run parallel with each other and the beetles jarred clown 
upon them. A lighter sledge (fig. 13), drawn by a man, was devised 
in 1909, but since the tanglefoot has proved so effective this sledge is 
unnecessary. 
Crude oil or tar. — Both crude oil and tar are effective when used 
on shields or sledges. Tar has more disadvantages, for on cold days 
it is very thick and on warm days dries rapidly, and in either condi- 
