A leaf punch for sampling insecticide residues on foliage

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Material Information

Title:
A leaf punch for sampling insecticide residues on foliage
Physical Description:
Book
Creator:
Fahey, Jack E
Rusk, Harold W
United States -- Bureau of Entomology and Plant Quarantine
Publisher:
U.S. Department of Agriculture, Bureau of Entomology and Plant Quarantine (Washington, D.C
Publication Date:

Record Information

Rights Management:
All applicable rights reserved by the source institution and holding location.
Resource Identifier:
aleph - 030361511
oclc - 783268931
System ID:
AA00023171:00001

Full Text
7ATE PLANT BOARD
March 1949 ET-264

United States Department of Agriculture
Agricultural Research Administration
Bureau of Entomology and Plant Quarantine



A LEAF PUNCH FOR SAMPLING
INSECTICIDE RESIDUES ON FOLIAGE

By Jack E. Fahey and Harold W. Rusk
Division of Insecticide Investigations


For studying residues of insecticidal dusts or sprays on foliage it is
desirable to have a simple, easily operated device for obtaining a known
area of leaf. Several such implements are described in the literature.
Fulton (1) gives specifications for a leaf punch employed in the study of
sulfur residues on citrus foliage. Lathrop et al. (2) have described a
method of cutting known areas of leaf surface for residue analysis. A. W.
Cressman of this Bureau has described in personal correspondence a leaf
punch which he has used for studying oil residues on foliage. It was de-
signed by L. H. Dawsey and is very similar to that employed by the
authors. It is therefore with no thought of originality, but rather to de-
scribe a useful tool that has not been described in the literature, that this
paper is prepared. A leaf punch has been designed which will cut a leaf
disc 0.75 inches in diameter and will deposit the disc in a sample-
collecting bottle. The punch with sample-collecting bottle attached
weighs approximately 1 pound and can be easily operated with one hand
leaving the other free to guide the leaf to be sampled into the cutting area.
The sampling device was constructed from a pair of pliers with
parallel-action jaws (Bernard pliers). To the jaws of these pliers were
attached (by brazing) 1/4-inch steel plates 11/2 inches by 2 1/3 inches which
had previously been fitted, one with a 3/4-inch ,punch and the second with
a die plate. Alignment of the punch and die plate is maintained by two
guides between the plier jaws; these guides also act as retainers for coil
springs which provide a return action for the pliers. Attached to the
bottom of the plier jaw carrying the die plate is a screw cap for a 2-ounce
sampling bottle which catches and retains the leaf discs cut by the punch
and die.
Two views of the punch are shown in figure 1.
The advantages of this device over similar apparatus are primarily
simplicity and convenience. The steel punch and die plate cut perfect
leaf discs and, when made of tool steel, will wear indefinitely. The leaf
disc is forced through the die plate by the punch and falls automatically
into the sampling container, which is readily attached to or removed from
the punch by a simple twist.





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UNIVERSITY OF FLORIDA

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3 1262 09240 9449


Literature Cited


(1) Fulton.
1942.


Robert A.
A leaf punch for use in insecticidal residue studies. Bur.
Ent. and Plant Quar. ET-189, 2 pp., illus.


(2) Lathrop, F. H., Plummer, Bernie E., and Dirks, C. 0.
1944. A simplified method of sampling known areas of apple leaves
for chemical analysis. Jour. Econ. Ent. 37: 294-295, illus.


Figure 1.--Foliage-samnpling machine: A, Assembled; B, dismantled to
show structural parts.