January I9U6 ^TATB^P^^'^ BOARD eT-226 nnit«d states D«partD«nt of A^n^leultor* A^leultural Eesearch Adndniatratlon Bureau of Entomology and Plant (^rantlne ▲ HIBXBHATIOH CAQJt lOB TEX PIK BOLLWOBM By Ivan Shiller. 1/ Dlrision of Pink Bollwora Control A hibernation cage that closely approximates outdoor conditions has long been recognized as essential in the biological studies of the pink bollwora ( Pectinephora gossypiella ( Saond. ) ) , The cage pre- Tlously used consisted of a >«foot«8quare frame made of 1- by S-inch boards with a remorable flat top corered with black sateen cloth, A 3-lneh hemispherical screen fly trap was installed in the center of the black cloth for trapping the emerging moths. The frame of the cage was buried 5 or 6 inches in the soil, and infested cotton bolls were placed on the soil surface or buried to the desired depth. The much hl^er temperature and humidity within the cage than outside stimulated an earlier-thas-normal emergence of the moth. Moreorer, the efficiency of the cage in trapping the moths was low. The cage described herein more closely simulates outside condi« tioas; its efficiency in capturing pink bollworm moths is high (82 percent), it can easily be cleaned of weeds since the corers are remorable, and it can be stored in a minimum of space inasmuch as the coTors can be telescoped into each other. Because of these advan- tages the cage may prove useful in the study of other insects. Meteorological records were taken inside and outside the cage at Presidio, Tex. , over an 18-day period. May 6 to 23, I9UI. The aver- age mean temperature 3 inohes above the soil was SU.S® T. inside the cage and 8^.3^ outside the cage; the respective maximum temperatures were 113** and 112* l^f and the minimum temperature was 68° in both cases. However, the variation in the soil temperature at the 2-inch depth was considerably greater; the average mean temperature was 71,2° inside the cage and 7U.3° outside, the maximum temperatures were 86° and 99*3°, and the minimum temperatures 31 •S9 and 32.7°. Svaporation outside the cage as measured in open metal pane was 1,860 ml« as compared with 1,U^ ml. Inside. As would be expected, the soil moisture was somewhat hi^er Inside the cage than outside, the percentages being 30*3 ^^^ ^•5* 1/ Acknowledgments are due to A. J. Chapman, L. V. Noble, and L. Lowry, who contributed to the development of this cage* - 2 - Materials and Constroetioci The following materials are required for one eaget Ltunber.CU pieces of each size): 7or base, 1 b7 8 bj 33 l/k Inches (A)-^ and 2 by 2 b7 7 1/2 inches (B); for reaoTable corer, 1 by 1 37^ >>7 36 3/8 inches (D). 1 by 1 3/^ by 37 1/8 inches (C), 1 by 1 3/8 by 3U 1/2 inches (I), screen molding 37 7/8 inches ~ long, and screen molding 3U 1/2 inches long. Hardware: g-o\ince glass Jar, with metal (preferably copper) cap, 3 inches high, having an opening 1 7/8 inches in diameter (?); 1 cone of l6-Besh screen wire 2 1/2 inches high and 1 7/g inches in diameter at the base to fit into the mouth of the jar (G); 2 pieces of l6-mesh screen wire 3^ inches wids cut into rhombic figures with all sides 39 l/k inches long so that the emgles in two opposite corners are 120® and in the other two 60® (fig. 2); and 1 metal ring 6 inches in diameter made of 1/2 by 1/8 inch strap with k holes 3/I6 inch in diameter and at 90® apart (H). The construction of the cage is shown in figures 1, 2, and 3, The base (fig, l) consists of four pieces of lumber (a)-^ nailed to four comer blocks (B) for added support and strength. This base is embedded U to 6 inches in the ground, and the sides are banked with soil. The remorable corer of the cage consists of a pyramid- shaped wooden frame corered with l6-mesh screen wire (figs. 1 and 3)* ^^« lower part of the corer is made by nailing the fotir pieces of lumber (D) at right angles to the four pieces (C) so that these pieces can fit tightly orer the base of the cage. The four ridge pieces of lumber (X) which support the screen pyramid are held in position by screws through the holes in the ring (H), The screen wire for the corer consists of two rhombic pieces (fig. 2), ^ich when folded along the center of the 120® angles and soldered together, fit orer the pyramid frame, learing a small open- ing at the apex. The screen is fastened on the wooden frame of the corer by the use of screen molding. •^Letters refer to the rarlous pieces of lumber and hardware as shown in figure 1 and in list of materials required for one cage. - 3 - The trap consists of an S-oxanco glass jar (7) with a aetal scrsv top and a small Innsr screen cone (O) that fits snugly inside the mouth of the jar. The screen cone (G) Is aade by forcing the screen vire orer a wooden fom of the proper site. While the screen cone is still on the form, a small strip of adhesire tape is placed on the wire aroond the base of the cone to maintain the shape. The cone is then remored, and the wire is trimmed along the bottom edge of the tape. ▲ second piece of tape holds the bottom edge of the screen cone in the mouth of the jar. An opening is made in the apex of the cone with an ice pick or sifflilcur instrument, its sise depending on the insects to be trapped. The center of the metal jar cap is cut out with about 3/^^ inch of the aetal left adjacent to the rim. This metal cap is then soldered to the top of the screen-wire pyramid so that the screw edge of the cap is upward. The glass jar containing the small screen cone is screwed into the metal cap and is readily removed for counting the insects and for cleaning* 'U- "\:^\' 30 -i -*- r-^ ^ 1 1. 3^ P/ECE E Figure 1. — Oblique croee-sectional drawing of hibernation cage, the letters referring to the same parte of lumber and hardware as given in the list of materials. The method of cutting piece E is also shown. -5- Fignre 2. — Th» two rhoataie pieeas are folded along the centar of the 120^ angles and soldered to fora the pjraBld coTer of the hibernation cage. -6- UNIVERSITY OF FLORIDA ilillilillliii 3 1262 09240 9019 Figure 3.-- Hibernation cages containing cotton bolls infested with pink bollwormB.