Abstract:
The invention provides a method and apparatus for detecting and controlling termites. The invention uses a tubular body with a triangular cross section to hold a cellulose bait impregnated with a slow acting toxicant. The tubular body is placed partly in the ground so that the length of the tubular body is along the surface of the ground. The top of the tubular body is transparent so that one can easily view the bait through the top of the tubular body.

Description:
This application is a Continuation of Ser. No. 08/794,097 filed Feb. 3, 1997 now U.S. Pat. No. 5,927,001. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention relates generally to the control of termites and other social insects. In particular, the present invention relates to the control of such insects using an apparatus containing bait impregnated with a slow acting toxicant. For a discussion of social insects, see generally U.S. Pat. No. 5,152,992. That patent is incorporated by reference herein to the extent it discusses social insects and their habits. 
     In the prior art, various techniques of applying fast acting insecticides in, around, and under a structure are used to eliminate social insects such as termites in the structure. For eliminating social insects in the ground vertical tubular stations were used. 
     SUMMARY OF THE INVENTION 
     It is an object of the invention to provide an apparatus and method for eliminating social insects in the ground. 
     The invention uses a cellulose bait impregnated with a slow acting toxicant held in a tubular container with a triangular cross section, which is placed horizontally in the ground. The tubular container and bait are designed to allow easy inspection of the bait without opening or moving the tubular container. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an exploded view of a preferred embodiment of the inventive bait station. 
     FIG. 2 is an sectional view of the inventive bait station shown in FIG. 1, along lines  2 — 2 . 
     FIG. 3 is a perspective the inventive bait station placed in the ground. 
     FIG. 4 is an exploded view of a bait station used in another embodiment of the invention. 
     FIG. 5 is a cross-sectional view of the bait station in FIG. 4 along cut lines  5 — 5 . 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     FIG. 1 is an exploded view of a preferred embodiment of the inventive bait station  10 . FIG. 2 is an sectional view of the inventive bait station  10  shown in FIG. 1, along lines  2 — 2 . The bait station  10  comprises a tubular body  12  and a cap  13 . A cellulose bait  14  impregnated with a slow acting toxicant is placed in the bait station  10 . 
     The tubular body  12  has a first side wall  16 , a second side wall  17 , and a top wall  18 , mechanically connected together to form the tubular body  12  with a triangular cross section. The first side wall  16 , second side wall  17  and top wall  18  are rectangular, and have the same length  19 . In this embodiment, the length  19  of the first side, second side, and top walls  16 ,  17 ,  18  is 31 centimeters. In other embodiments the length may range from 2.5 centimeters to 1 meter. The first side wall  16  and second side  17  wall have the same width  20 . In this embodiment the width  20  of the first and second side walls  16 ,  17  is 7 centimeters. In other embodiments, the width may range from 1 centimeter to 30 centimeters, with the length  19  always being greater than or equal to the width  20 . The first side wall  16  and the second side wall  17  have a plurality of apertures  21 . The apertures  21  are preferably between 1 and 6 millimeters in diameter. The apertures  21  may be between 0.5 and 12 millimeters in diameter. An end wall  25  has a triangular shape and is mechanically connected to first ends of the first wall  16 , second wall  17 , and top wall  18 . In the preferred embodiment, an adhesive is used to mechanically connect the end wall  25  to the first side wall  16 , the second side wall  17 , and the top wall  18 . The top wall  18  is transparent. In the preferred embodiment, the first side wall  16 , the second side wall  17  and the top wall  18  are mechanically connected together by forming the first side wall  16 , the second side wall  17  and the top wall  18  out of a single transparent sheet, which is bent to provide three edges, thus forming a tubular body with a triangular cross section, wherein the edges define the first side wall  16 , the second side wall  17 , and the top wall  18 . An open end is opposite from the end wall  25 , formed by unbound edges of the first side wall  16 , the second side wall  17 , and the top wall  18 . A bottom edge  22  is the edge where the first side wall  16  joins the second side wall  17 . A groove  23  is place adjacent to the open end of the tubular body  12 , across the widths of the first side wall  16 , second side wall  17 , and top wall  18 . The groove  23  has a substantially rectangular cross-section. The edge of the open end has a beveled surface  24  around the open end of the tubular body  12 . 
     The cap  13  has a triangular end wall  29 . Along the edges of the triangular end wall  29  is an outer flange  30  mechanically connected to the end wall  29 . Within the outer flange  30  is a ridge  31 . In this embodiment, an adhesive is used to mechanically connect the outer flange  30  to the end wall  29  of the cap  13 . The outer flange  30  and the end wall  29  may also be molded from a single piece. A screw hole  35  is placed through the outer flange  30 . 
     The cellulose bait  14  comprises one or more blocks  43  of a cellulose material. The width  44  of the blocks  43  is less than the width  20  of the first side wall  16  and second side wall  17 . The blocks  43  have a length  45  which is longer than the width  44  of the blocks  43 . A first side  48  of the block  43  extends along the width  44  and length  45  of the block  43 . A second side  49  of the block  43  is opposite from the first side  48  and extends along the width  44  and length  45  of the block  43 . A first plurality of slots  51  are cut into the first side  48  of the block  43 , where the first plurality of slots  51  are parallel to each other and spaced apart from each other. A second plurality of slots  52  are cut into the second side  49  of the block, wherein the second plurality of slots  52  are parallel to each other and spread apart from each other and where the second plurality of slots  52  alternate with the first plurality of slots  51  as shown. The first and second plurality of slots  51 ,  52  have a width of  3  centimeters. In other embodiments, the first and second plurality of slots  51 ,  52  have a width in the range between 0.5 centimeters and 7 centimeters. FIG. 2 shows how three blocks  43  of the cellulose material are placed in the bait station  10 . 
     The cellulose bait  14  is impregnated with a slow acting toxicant. The slow acting toxicant may be any toxicant that requires more than 24 hours and less than 6 months after ingestion of a termiticidally effective amount to kill a termite. Slow acting toxicants useful in the present invention include, but are not limited to: boric acid/borate, hydramethylnon, macrolide antibiotics (e.g., spinosyn A and/or D, and abamectin), insect growth regulators such as molting disrupters or juvenile hormone agonists/antagonists, biological agents (i.e., living organisms or their reproductive stages), protozoacides, known termiticides, slow acting poisons or mixtures thereof. Specific examples of molting disrupters include chitin inhibitors, particularly benzoylureas such as hexaflumuron. 
     In operation, the bait  14  is placed in the tubular body  12 . The blocks  43  are positioned, so that the length  44  of the blocks  43  is along the length  19  of the tubular body  12 , and the width  44  of the blocks  43  extends along a direction from the top wall  18  to the bottom edge  22 , as shown in FIG.  2 . The cap  13  is placed over the open end of the tubular body  12  so that the outer flange  30  surrounds part of the first, second, and top walls  16 ,  17 ,  18 . The ridge  31  slides into and locks with the groove  23  securing the cap  12  to the tubular body  12 . A screw  55  is placed through the screw hole  35  in the outer flange  30  to further secure the cap  13  to the tubular body  12 . The bait station  10  is placed horizontally in the ground, so that the length  19  of the first side wall  16  is horizontal with the ground, as shown in FIG.  3 . The bait station  10  may be pushed directly into soft ground, or a trench as long as the length  19  of the first side wall  16  is dug. The bottom edge  22  is positioned at the bottom of the bait station  10  in the ground, and the top wall  18  is positioned at the top of the bait station  10 , slightly above or almost even to the surface of the ground  58 . The triangular cross section makes it easier to place the bait station  10  in the ground. 
     Once in the ground, the bait station  10  is able to intercept termites which travel underground in a horizontal direction. The termites enter the bait station  10  through the apertures  21 , which are holes ⅛ inches in diameter. Once inside, the termites begin to build termite tubes to the cellulose bait  14 . The termites eat the bait, taking in the slow acting toxicant. The termites go back to the colony before the slow acting toxicant kills the termite, and share the bait with the rest of the colony. This provides the slow acting toxicant to the colony, thus killing the whole colony. Therefore the invention provides a means for controlling a termite colony. The controlling of a termite colony means any of the following: the killing of the whole colony, or stopping the destruction caused by the colony, or substantially eliminating the colony. 
     The first and second plurality of slots  51 ,  52  enhances the baits  14  attractiveness to termites, since it is easier to build termite tubes in slots of such size. In addition, the position of the slots allows one to see through the top wall  18  and inspect the bait  14  for the presence of termites and termite tubes without moving or touching the bait  14  or station  10 . The horizontal positioning also allows the easy inspection of the bait  14 , which cannot be done with bait stations where the length of the station is positioned vertically in the ground. 
     Because termites tend to travel horizontally, just below the surface of the ground, placing the length of the bait station  10  horizontally, allows the bait station  10  to provide a greater area of protection. A plurality of bait stations  10  may be placed end to end to provide a linear barrier, such as a circle around a house. In addition to making it easier to place the bait station  10  in the ground, the triangular cross section and the absence of uncovered holes in the top wall  18  helps to keep water from reaching the apertures in the first and second side walls  16 ,  17 . The apertures  27  in the end wall  25  and the cap end wall  29  are angled downward as shown in FIG. 2 so that water passing downward from the surface of the ground to the bottom edge  22  on the out side of the station will not enter the apertures in the end wall  25 . The positioning of the apertures also help to keep soil out of the tubular body  12 . 
     FIG. 4 is an exploded view of a bait station  110  used in another embodiment of the invention. FIG. 5 is a cross-sectional view of the bait station  110  in FIG. 4 along cut lines  5 — 5 . The bait station  110  comprises a tubular body  112  and a cap  113 . 
     The tubular body  112  has a first side wall  116 , a second side wall  117 , and a top wall  118 , mechanically connected together to form the tubular body  112  with a triangular cross section. The first side wall  116 , second side wall  117  and top wall  118  are rectangular, and have the same length. The first side wall  116  and second side  117  wall have the same width. The first side all  116  and the second side wall  117  have a plurality of apertures  121 . An end wall  125  has a triangular shape and is mechanically connected to first ends of the first wall  116 , second wall  117 , and top wall  118 . In this preferred embodiment, the end wall  125  to the first side wall  116 , the second side wall  117 , and the top wall  118  are mechanically connected by forming the first side wall  116 , the second side wall  117 , the top wall  118  and the end wall  125  from a single molded piece of transparent plastic. An open end is opposite from the end wall  125 , formed by unbound edges of the first side wall  116 , the second side wall  117 , and the top wall  118 . A bottom edge  122  is the edge where the first side wall  116  joins the second side wall  117 . 
     A cardboard bait  114  impregnated with a slow acting toxicant is placed in a bait holder  128 , which is placed in the bait station  110 . The slow acting toxicant may be any toxicant that requires more than 24 hours and less than 6 months after ingestion of a termiticidally effective amount to kill a termite. Slow acting toxicants useful in the present invention include, but are not limited to: boric acid/borate, hydramethylnon, macrolide antibiotics (e.g., spinosyn A and/or D, and abamectin), insect growth regulators such as molting disrupters or juvenile hormone agonists/antagonists, biological agents (i.e., living organisms or their reproductive stages), protozoacides, known termiticides, slow acting poisons or mixtures thereof. Specific examples of molting disrupters include chitin inhibitors, particularly benzoylureas such as hexaflumuron. 
     In this preferred embodiment, the bait holder is made of a rigid foam, such as Styrofoam™, which is a rigid polystyrene plastic. The bait holder  128  has a generally triangular cross section so that it fits into the bait station  110 . A slot is placed in the top of the bait holder  128 , so that the cardboard bait  114  may be placed in the slot at the top of the bait holder  128 . Since the cardboard bait  114  is placed in a slot in the top of the bait holder  128 , the cardboard bait  114  may be viewed by looking through the transparent top wall  118 . In this preferred embodiment, the cardboard bait  114  is formed by a plurality of layers of corrugated cardboard. Corrugated cardboard is formed from a piece of corrugated paper  130  sandwiched between and adhesively connected to layers of flat paper  131 . The corrugations in the corrugated paper  130  forms ridges and valleys which form holes between the corrugated paper  130  and the layers of flat paper  131 . The ridges and valleys extend away from the top wall  118 , so that the operator is able to look through the top wall  118  and down the holes between the corrugated paper  130  and the layers of flat paper  131 . 
     The cap  113  is a triangular end wall. The cap  113  is mechanically connected to the first side wall  116 , the second side wall  117 , and the top wall  118  by an adhesive, sealing the cardboard bait  114  and the bait holder  128  in the bait station  110 . 
     In operation, the impregnated cardboard bait  114  is placed in the slot on top of the bait holder  128 , which is then placed in the tubular body  112 . The cardboard bait  114  is positioned, so that the holes caused by the corrugated paper  131  extends from the top wall  118  towards the bottom edge  122 , as shown in FIG.  4 . The cap  113  is placed over the open end of the tubular body  112 , and is mechanically connected to the first, second, and top walls  116 ,  117 ,  118  by an adhesive. The bait station  110  is placed horizontally in the ground. The bait station  110  may be pushed directly into soft ground, or a trench The bottom edge  122  is positioned at the bottom of the bait station  110  in the ground, and the top wall  118  is positioned at the top of the bait station  110 , slightly above or almost even to the surface of the ground. The triangular cross section makes it easier to place the bait station  110  in the ground. 
     Once in the ground, the bait station  110  is able to intercept termites which travel underground in a horizontal direction. The termites enter the bait station  110  through the apertures  121 , which are holes ⅛ inches in diameter. Once inside, the termites begin to build termite tubes through the bait holder  128  to the cardboard bait  114 . The termites eat the cardboard bait  114 , taking in the slow acting toxicant. The termites go back to the colony before the slow acting toxicant kills the termite, and share the bait with the rest of the colony. This provides the slow acting toxicant to the colony, thus killing the whole colony. 
     Therefore the invention provides a means for controlling a termite colony. The controlling of a termite colony means any of the following: the killing of the whole colony, or stopping the destruction caused by the colony, or substantially eliminating the colony. 
     The corrugation in the cardboard bait  114  enhances the cardboard bait&#39;s  114  attractiveness to termites, since it is easier to build termite tubes in the holes formed by the corrugation. In addition, the position of the holes allows one to see through the top wall  118  and inspect the cardboard bait  114  for the presence of termites and termite tubes without moving or touching the cardboard bait  114  or station  110 . The horizontal positioning also allows the easy inspection of the cardboard bait  114 , which cannot be done with bait stations where the length of the station is positioned vertically in the ground. 
     Because termites tend to travel horizontally, just below the surface of the ground, placing the length of the bait station  110  horizontally, allows the bait station  110  to provide a greater area of protection. A plurality of bait stations  110  may be placed end to end to provide a linear barrier, such as a circle around a house. In addition to making it easier to place the bait station  110  in the ground, the triangular cross section and the absence of uncovered holes in the top wall  118  helps to keep water from reaching the apertures in the first and second side walls  116 , 117 . The apertures in the end wall  125  are angled downward, so that water passing downward from the surface of the ground to the bottom edge  122  on the out side of the station will not enter the apertures in the end wall  125 . 
     The bait holder  128  also keeps water away from the cardboard bait  114 , preventing the cardboard bait  114  from degrading. 
     Other embodiments of the invention may provide other types of caps. Such caps may also have apertures. In other embodiments, neither the caps or end walls have apertures. In another embodiment, the adhesive may be replaced by having the parts form a single piece. The adhesive, screw holes, or making a single piece are various ways of mechanically connecting the various parts. 
     While preferred embodiments of the present invention have been shown and described herein, it will be appreciated that various changes and modifications may be made therein without departing from the spirit of the invention as defined by the scope of the appended claims.