STATE PLANT BOARD 
 
 ET-176 August 1941 
 
 United States Department of Agriculture 
 Bureau of Entomology and Plant Quarantine 
 
 AN IMPROVED SPRING CAGE FASTENER 
 
 By E. W. Davis and C. H. Feltes, 
 Division of Truck Crop and Garden Insect Investigations 
 
 With the advent of specialized entomological research, it 
 has become necessary to cage insects on growing plants. In order 
 to facilitate the study of the insects so caged, the plants are 
 generailly planted in flowerpots. Consequently it becomes neces- 
 sary to attach the cage firmly to the flowerpot. Cages of various 
 shapes and materials have been constructed. Each type has been 
 designed to meet the special requirement of the insect studied. 
 The characteristic that is common to them all is that they need to 
 be fastened to the pot upon which they are used. 
 
 Several fastening devices have been developed for attaching 
 cages of the open-bottom type. J. N. Tenhet (ET-14) described a 
 flat band on the bottom of the cage that can be tightened by means 
 of a stove bolt. T. E. Bronson {ET-22) described a v,'ay of drilling 
 holes in the upper part of the pot and using nails to attach the 
 cage. R. L. Wall is (ET-48) described a band on the bottom of the 
 cage, using an overshoe buckle for the tightener. All these are 
 ;-='.uccessful for cages with open bottoms but cannot be used with cages 
 that have closed bottoms. 
 
 During the progress of investigations of the sugar beet leaf- 
 hopper (Eutettix tenellus (Baker)) it was found necessary to con- 
 struct special cages to hold this small, elusive insect. It was 
 found that many leafhoppers escaped or were lost if they had access 
 to the soil of the pot. For this reason the beet leafhopper cages 
 were constructed with o rigid solid bottom with provision for the 
 insertion of the plant. This type of cage must rest on the soil 
 within the pot or on the top of the pot. The disadvantage of this 
 type of cage is that it is very susceptible to displacement by a 
 light touch or wind. 
 
 After trying all fastening methods that have been published 
 and a number of others, a sim.ple fastening device has been designed 
 that will attach closed-bottom cages to flowerpots of various sizes. 
 This fastener can. with slight modifications, be used to hold cages 
 of most any size, shape, or material. 
 
- 2 - 
 
 Construction 
 
 The materials needed for the construction of this device in- 
 clude some 12- and 25-gauge (American standard) wire and two No. 87 
 cadmium-plated springs (3/8 inch by 3 1/8 inches) . A vise, a pair 
 of large pliers, a hammer, and either a hacksaw or bolt cutters for 
 cutting the large-gauge wire, are the tools required for making the 
 assembly. The component parts as pictured in figure A, numbers 1 
 to 8, are cut for an 8-inch pot, such as is used at this laboratory. 
 First cut tv/o pieces of 12-gauge wire 18^ inches long (fig. A-1 ) . 
 Make marks on each wire 2^ inches from one end and 3 inches from the 
 other end. Now set a 20-penny nail in the vise and bend an eye in 
 each wire at the end marked at 2^ inches, as in figure A-2. Then 
 bend these v/ires at right angles at the 2|— inch marks (fig. A-3) and 
 also at the 3-inoh marks, and shape them to the design of figure A-4 
 by bending them around a flowerpot with the hands. 
 
 To put these two pieces together, wrap the straight end of 
 each wire around the opposite wire back of the eye bend, as shown 
 in the completed circle of figure A-8. At this stage the eye loops 
 will be projecting straight out. It is now necessary to bend them 
 upward at right angles i inch distant from the circle in order to 
 get around the shoulder of the pot, as can be seen in figure B. 
 Cut two lengths of 25-gauge wire 7 inches long and make eyes in both 
 ends of both pieces (fig. A-7) , attaching one end of each piece to 
 the eye of the circle. Fasten the springs in the other ends 
 (fig. A-6) . These springs are hooked to a wire bent over the top r 
 
 of the cage, as shown in figure A-5 for wooden cages, or to hooks 
 soldered to a metal cage, as shown in figure B. Now you have the 
 assembly as pictured in figure A, numbers 5 to 8. 
 
 ^ 
 
Figure A. — Details of the construc- 
 tion of the spring cage fastener. 
 
 i 
 I 
 
 Figure B. — Spring cage fasteners in 
 position for holding cages on 
 flowerpots . 
 
UNIVERSITY OF FLOmDA 
 
 3 1262 09240 9316