1 1 n rs. 1 5 
inclosed space which permits of economical use of chemicals with 
greater uniformity of results. 
( instruction of tints. The const met ion of the box covers such as 
suggested in the foregoing paragraph Is a simple matter and con- 
venient patterns will suggest themselves at once to anyone desirous 
of fumigating small trees. The framework should be lighl hut well 
braced, and for a covering either 6J-ounce drill, painted to render it 
as nearly gas-tight as possible, or oilcloth is recommended. 
Prof. C. W. Woodworth, of the California experiment station, 
gives the following directions for cutting the (doth for bell tents:" 
All of these tents are made in the same manner, and arc the most economical in 
cloth of any tents made. Commonly the tent is made by the " cul and fit" method. 
These tents may l>e made with scarcely any loss, if cul according to Hie following 
directions: Measure oil' strips <»i" a length equal to twice i he heighl plus one-tenth ! he 
diameter of the tent desired. These will make two strips each by marking the exact 
middle and measuring off on one edge from the middle line one-quarter of the diameter 
of the tent and on \ he ot her one-half 1 he diameter. Now, take a long si rip of molding 
and bend it so as to touch these three points and mark off the curve so produced. 
This allows lor the seam. In making up. sew the two cut edges together in each pair 
of si rips. 
As has been stated, sheet tents, or more properly covers, are flat, 
regular octagons. The dimensions are sometimes stated in terms of 
the true diameter (i. e., the distance between opposite corners), 
but for practical purposes the distance between parallel sides should 
represent the size of the tent, for the reason that this represents 
within about 2 feet (which must be allowed to rest on the ground) 
the distance over the tallest tree that a given sheet can cover meas- 
uring from the ground on one side to the ground on the other, over 
the center of the tree. 
Hereafter in this bulletin the size of octagon covers as stated should 
be understood to refer to the distance between parallel sides. The 
specifications should be carefully worked out before beginning the 
construction of a sheet tent as well as of other styles. First, the 
dimensions of the tallest tree which the tent is required to cover 
should be estimated. This may be accomplished by throwing a tape 
attached to a reel over the top of the tree and measuring from ground 
to ground. When covered, the weight of the tent will reduce the 
extreme height of the tree in most cases by from 2 to 4 feet, 
according to the weight of the tent and form of the tree. It will be 
well to allow at least 4 feet of the tent to rest on the ground when 
covering the largest tree. The desired size having been determined, 
a diagram of an octagon should be constructed on paper, as indicated 
in figure 1. Each side of the octagon when constructed will be 
equal approximately to two-fifths of the distance between the parallel 
" Circular No. 11, Cal. Agr. Exp. Sta., pp. 9-10. 
mi8— Bull. 7(3—08 2 
