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E-434 May 1938
HUnited States Department of Agriculture
Bureau of Entomology and Plant Quarantine
AN EFFICIENT METHOD FOR INTRODUCING LIQUID CHEMICALS INTO
By A. E. Lantz, Division of Forest Insect Investigations
In connection with the project for Dutch elm disease eradication and
control it has been found that the presence of large numbers of w..oodland
elms in the infected area seriously hampers the progress of the work. Ex-
periments have therefore been conducted to determine how such trees can be
treated with chemicals so as to kill them in a satisfactory way and prevent
subsequent attack by bark beetles. The prevention of bark beetle attack is
important because of the part played by certain species in spreading the
fungus that causes the disease.
A satisfactory method of applying liquids so that they will be ab-
sorbed by elm trees has been devised and is here described. While it has
been used only for elm trees, it is believed that it can be used just as
satisfactorily for other species. The collar method consists essentially of
applying a piece of waterproof material to the tree in such a manner as to
form a receptacle capable of holding liquids. With methods previously em- ,
played it was necessary to return to the scene of operation to salvage the 2
costly materials used. With the present method the cost is sufficiently low
to make salvaging unnecessary, and less skill and fewer tools are required.
Rubberized Fabric Collar-
Rubberized fabric is best suited for the collar material whrn the
dosage is based on a diameter unit. It could be used, however, when do.-ages
are based on a volume unit. provided the dissolving of the chemical uL--'-ed re-
quired relatively small quantities of liquid. At this point it might be well
to explain that when dosages are based on a diameter unit. the collar width
is not changed with the diameter of the tree, but is varied only when the
solubility of different chemicals or changes in dosage require it. If dosages
are determined by the volume, however, it will be necessary to increase the
width of the collar as the tree size is increased. On fairly large trees
the increase in material might be prohibitive unless it could be salvaged.
1 The technique described herein is an improvement over that given J in
E-409, A Method for Preventing Insect Injury to Material Used for Posts,
Poles, and Rustic Construction, by F. C. Craighead, R. A. St. George. and
B. H. Wilford.
Tools required.--l tree tape, 1 light hammer, 1 hand axe, 1 draw-
knife, 1 putty knife, 1 pencil, 1 liquid measure, 1 short 1-inch chisel
(preferably having a composition and steel handle).
Material required.--Asphaltum roofing compound, No. 10 tacks, and
rubberized sheeting. The sheeting can be purchased in quantities for 25
cents per square yard.
Directions for application.--First measure the tree to determine the
dosage to be used. Then, using the draw-knife with the beveled side toward
the tree, shave off the outer bark. The width of this shaved area will
depend on the width of the collar used. Next, using the tree tape as a guide,
make a pencil mark around the tree about one-third of the way up from the
lower edge of the smoothed area. Then make a kerf along this pencil line by
repeated chisel cuts which should cut through from three to four annual
rings. Hold the chisel with the beveled side toward the bole of the tree
and with the handle pointing upward at an angle of about 45. The tree at
this point will appear as in figure 1.
Now tear a strip from the rubberized fabric 1 inch wider than the
desired width of the collar. Wrap this strip of material around the smoothed
area to get the measurement. Make a suitable allowance (table 1) for pleat-
ing, and tear off the material needed. Then tear a 1-inch strip lengthwise
from this piece to use later as a band. Start tacking the collar to the tree
with the lower edge about A inch below the chisel kerf, making 3-inch pleats
every 2 inches around the circumference. The collar should now appear as in
Next, apply a band of asphaltum compound where the ends of the collar
join, and tack this junction to the tree every l1 inches. Also apply a band
of the same material around the base of the collar so that half of it will
be over the pleated edge of the collar and half on the tree trunk. This / (
stage is illustrated in figure 3.
Now tack one end of the 1-inch strip of rubberized fabric, previously
torn off, into the compound along the lower edge of the collar, draw the
strip tightly around the tree, press it into the compound, and tack it again.
If the surface of the trunk is uneven it may be necessary to put additional
tacks at any indentations. The completed collar will appear as in figure 4.
Table 2 is given to show the approximate quantity of material that
collars of various sizes will hold. These are approximations, since the
collars will vary as made by different workmen. They may be made up to 12
inches wide, but collars over 12 inches are inadvisable. It would be pref-
erable to refill a narrower collar.
In a second method which has also been successful, a collar of water-
proof crepe paper has been employed. Its use is retricted to comparatively
small dosages, but in such cases it is quite desirable, because it can be
applied more rapidly than the rubberized-fabric collar and the material is
The material Is -.a.., in rolls 3 feet wide ccn.poc.-,dJ of two thin sheets
of paper, with a tar cmpoTition between the two, and the assembly is cor-
rugated. It is ln.pc-pervlcius to mo:t chemicals, but .-,,-, ai:u' em c,'dine,
acetic acid, and formaidc-hyde, do attack it.
The collar material is prepared before goin-, into the field. T.:,. is
done by cutting the roll into strips the desire width. One-inch .T.-.,ir:g
tape (this is the cloth type similar -to adhesive papc-r tape) is strc' along
one edge by rubbing with a piece of round woo:l or a roller. These strips
are made in rolls of about 50 feet each.
Method cf ar._Fl, ir', icn.--Prepare the tree as for the rbberized-fabric
collar. (See fig. 1.) Next apply a band of a-.lal!tum compound to the tree
about if inch below the chisel kerf. Then cut the cr,-p;. Fc!p',r material about
1 inches longer than the circumference of the shaved area, and pull the
corrugations out of the paper by placing the p''per bet,-:n the palm of ore
hand and the thigh and [;.'.llir- it through with the other 'ld. The +ape
prevents any stretching along the one edge.
With the tape on the outside, tack one end of this taped -,ge into
the asphaltum and then, holding, the other end of the tOpe-d E:':,e, pull it
tightly into the compound and tack this end. An occasional tack at any
indentations may be nece:-.ary to prevent leaks at these points.
Join the ends of 3'1.o collar and seal them in the same manner as with
the rubberized-fabric collar.
Table 3 gives the approximate capacity of this ty.,? of collar. Figure
5 shows the completed collar.
Table l.--Allowance for pleats andc lap in collars to be applied to trees of
Diameter of tree Allowance for Diameter of tree Allowance for
at breast height pleats and lap at breast height pleats an-! lap
Inches Inches Inches Inches
3 4 12 13
4 4 13 14
5 5 14 16
6 6 15 17
7 7 16 18
8 9 17 19
9 10 18 20
10 11 19 12
Table 2.--Quantity of material that can be held by the rubberized-fabric
collars of different widths
inch of tree
Collar width 1
inch of tree
iThis is the total width of the collar material. The actual collar will
be 1 inch less than this, since a strip is torn off to be used in sealing
the bottom of the collar.
Table 3.--Quantity of material that can be held by
paper collars of different diameters
the waterproof crepe-
inch of tree
inch of tree
Explanation of Figures
Figure l.--Portion of tree trunk prepared for receiving a collar of either
fabric or crepe paper.
Figure 2.--The rubberized fabric collar tacked to the tree trunk, showing
the pleats in the lower edge of the material.
Figure 3.--The asphaltum compound has been applied to the union of the two
ends of the collar and over the joint between the pleated edge
and the trunk.
Figure 4.--The complete collar of rubberized fabric with the 1-inch strip
drawn tightly around and pressed into the band of asphaltum.
Figure 5.--The completed crepe-paper collar as attached to a tree.
Figure 5.--The completed crepe-paper collar as attached
to a tree.
U3 R 'f P
STATE PLANT BOARD
UNIVERSITY OF FLORIDA
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