Abstract:
A novel method of positively directing termite activity by the use of radio waves. Also provided is a method of protecting a natural or man-made structure from termite infestation based on termite attractancy of specific radio waves.

Description:
This application claims priority from U.S. Provisional Application Ser. No. 60/304,424 filed Jul. 12, 2001. The entirety of that provisional application is incorporated herein by reference. 
    
    
     This invention was made with Government support under 19-94-111 and 19-94-112 awarded by the U.S. Department of Agriculture/Forest Service. The Government may have certain rights in this invention. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to the field of termite control technology and more specifically to a novel method of controlling termite activity by the use of radio waves. More particularly, this invention provides a method of attracting termites to a desired location by the use of radio waves within a certain frequency range. 
     2. Background of the Technology 
     Untreated termite infestation in homes leads to irreversible structural damage in buildings throughout the world. As a result, a myriad of treatments to control or destroy termite populations have been developed. Because of the potential negative environmental impact of insecticides, environmentally friendly alternatives have been the primary focus of the latest research. 
     A significant amount of prior art focuses on the use of electromagnetic fields to control (repel and/or negatively affect) termites. U.S. Pat. No. 5,473,836, issued to Liu discloses a method for removing insects from “hidden places” by inducing an electromagnetic field to create physical vibrations. U.S. Pat. No. 5,930,946 issued to Mah discloses a method for creating an to which pests react adversely. U.S. Pat. No. 5,442,876 issued to Pederson discloses a method for controlling termites by heating the area where termites are located to temperatures which are lethal to living organisms by means of electromagnetic energy. U.S. Pat. No. 4,870,779 issued to Bergerioux et al. discloses a method in which a low frequency, randomly varying magnetic field is generated by a device such that it interacts with the earth&#39;s geomagnetic field to eliminate (repel) rodents and similar pests located above and below ground level in the area surrounding the device. 
     The use of electrical energy has also been employed in efforts to eliminate (repel and/or negatively affect) termites. U.S. Pat. No. 5,210,719 issued to Lawrence discloses an apparatus and method which uses a sweep-frequency, high voltage generator coupled to an applicator gun for feeding electric power into pest-infested dielectrics, for example termite-infested wood. U.S. Pat. No. 4,366,644 issued to Lawrence discloses a method that involves the application of broad band radio frequency or multifrequency high-voltage electrical energy to termite shelter tubes, galleries and nests and to the bodies of termites in those areas. Lawrence &#39;644 teaches that by that method termites are killed directly by electroshock or indirectly by creating interference with the digestive processes of termites. U.S. Pat. No. 4,782,623 issued to Lawrence discloses an apparatus and phase-locked high voltage, high frequency pulse generator capable of “quasiunlimited” power output and an applicator gun for feeding electric power into pest-infested dielectrics, for example termite infested wood. U.S. Pat. No. 4,223,468 issued to Lawrence discloses a method that involves killing termi application of broad band, high voltage electrical energy to habitats of termites. 
     The application of microwave energy has also been employed in the attempt to control (repel and/or negatively affect) termites. U.S. Pat. No. 5,575,106 issued to Martin et al. discloses a method of using low voltage “microwave horns” to kill termite populations. U.S. Pat. No. 5,896,696 issued to Stokes et al. discloses an apparatus and method for generating and radiating energy at specific wavelengths for the purpose of adversely affecting the nervous systems of “small insects.” 
     While recent efforts to discover environmentally friendly methods of controlling termites have sought to avoid the use of conventional pesticides; they have failed to adequately protect termite-susceptible structures from infestation. Both conventional chemical and more modem methods alike seek to deal with the problem of termite infestation by killing termites in the area that is infested rather than providing a method by which termite infestation and subsequent structural damage can be prevented. The inventors have discovered a novel method by which the application of radio waves to a selected area can attract termites to that area and thereby provide protection from termites for other adjacent areas. 
     SUMMARY OF THE INVENTION 
     This invention relates to a method of controlling termite activity by emitting radio waves that attract termites to toxic baits, light traps, etc. or directing their movements away from susceptible structures. 
     It is therefore an object of the present invention to provide a system for transmitting radio waves of specific frequencies to an area where termite activity is desired. 
     It is also an object of this invention to use detection devices that monitor radio waves and/or energy levels of specific frequencies as a means to determine which structures are likely to attract termites. 
     It is also an object of the present invention to provide a radio wave transmitting system that is associated with proximately positioned termite bait stations, wooden stakes, wooden posts, or other termite-degradable materials to augment the termite attraction features of the radio wave transmitting system. 
     It is also an object of the present invention to provide a method of protecting termite-degradable materials of a natural or man-made character in a protected area by providing a radio wave transmitting system in an adjacent radio transmission area so as to attract termites to the transmission area and away from the protected area. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         FIGS. 1A-D  show diagram representations of different example embodiments of the radio wave transmitting system of the present invention. 
         FIGS. 2A-C  provide diagrammatic representations of the test area for the transmitting system of the present invention having both active and inactive transmission areas.  FIG. 2A  shows the disposition of antenna arrays within the test area.  FIG. 2B  shows the location of termite activity within the test area that were identified in 1998.  FIG. 2C  shows the location of termite activity within the test area that were identified in 2002. 
         FIG. 3  shows a diagram of antenna arrays associated with a radio transmitter and the location of wooden poles, which served as termite attractants in the area of the antenna arrays. The shaded areas indicate termite activity. 
         FIGS. 4A-G  show diagrams of different antenna arrays and circumferentially positioned wooden poles for antenna arrays. The absence of shaded areas in the diagram indicates no new termite activity. 
         FIGS. 5A-H  show diagrams of antenna arrays and circumferentially located wooden poles for active antenna arrays. The presence of shaded areas in the diagram indicate wooden poles having evidence of termite activity. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The present invention as described below and shown in the accompanying figures is a novel method of attracting termites that is employed to provide a method of controlling termite activity by emitting radio waves of a certain frequency. 
     As best shown in  FIGS. 1A-D  the radio wave transmitting system of the present invention, generally shown at  10 , can be configured to position at least one transmitting device  12  in a transmission area  14  where termite activity is desired. A radio transmitter  16  is designed to provide a broadcast radio signal of a certain wave length within a transmission area  14 . As shown in  FIGS. 1A and 1C  the transmitter  16  can be operationally connected to more than one transmitting device  12 . 
     As shown in  FIGS. 1A-D , the radio wave transmitting system of the present invention can have varied configurations where the transmitting devices  12  can be positioned adjacent to or circumferentially disposed around a natural or man-made termite-degradable structure  18  for which protection from termite damage is desired. The structure  18  can have a degradable component and therefore be susceptible to termite damage. The different transmitting system configurations depicted in  FIGS. 1A-D  are non-limiting examples, the pattern of which can be widely varied without departing from the concept of the present invention. 
     Within the effective range of the transmission area  14  natural or man-made termite-degradable materials can be positioned so as to provide an attractant  20  for termites that is localized within the transmission area  14 . Inclusion of the attractant  20 , in addition to increasing the effectiveness of the termite-attraction of the transmitting device  12 , also provides foci for termite infestation in the transmission area  14 . By focusing the relocation of the termites to the attractant  20 , subsequent containment, collection, or elimination of the termites by conventional means can be facilitated. 
     The transmitter  16  of the present invention can be any conventional radio wave transmitter capable of transmitting radio waves having a frequency range of about 1 to 100 megahertz and preferably 1 to 30 megahertz. The intensity of the radio wave transmission can be about 
     After conducting tests over a 10-year period, the inventors discovered that termites are attracted to radio waves within a certain frequency range and broadcast intensity. The inventors discovered that termites such as  Coptotermes formosanus  are attracted to radio waves such as those employed in the present invention. Species such as  Coptotermes, Reticulitermes and other termite genera can be susceptible to the attraction qualities of the present invention. Unlike conventional remedial termite control methods, the present invention provides a method to control subterranean, surface, and dispersal flight movement of termites before infestation of an area in need of protection. The inclusion of attraction augmentation in the transmitting system  10  of the present invention further permits the localization of the termites within the transmission area. The optional attractant  20  used in the transmitting system  10  can be any material to which termites can be attracted, to include, for example natural or man-made wooden items, bait stations, or any object with a termite-degradable component. 
     The present invention can be used to attract termites to the transmission area  14  for containment, collection and study, or elimination. By properly positioning the transmitting system  10  relative to a natural or man-made structure  18  for which termite protection is desired, the termites can be attracted away from the material or structure  18  that is to be protected and drawn towards the transmitting system  10 . Non-limiting examples of transmitting system configurations which can be used to provide protection for a material or object, such as a house, fence, utility pole, or any material subject to termite infestation are shown in  FIGS. 1A-D . 
     EXAMPLES 
     Field observations of the natural populations of the termite  Coptotermes formosanus  on the Lualualei Naval facility, Oahu, Hi. were conducted over a 10-year test period. These field observations indicated that movements of this subterranean termite are affected by radio waves of a frequency about 1-100 megahertz, preferably about 1-30 megahertz, and more preferably about 2-20 megahertz. The intensity of the radio transmission can be about 1-100 kilowatts; preferably about 1-10 kilowatts. Antenna arrays were formed of wires supported by large pressure-treated Douglas-fir wooden poles and were located over a large portion of the facility. The frequency of the radio waves ranged from about 1-100 megahertz at transmission intensities from about 1-100 kilowatts. 
       FIG. 2A  is a diagrammatic representation of the disposition of antenna arrays within the test area. In  FIGS. 2A-C , the diagram of the test area is divided into an eastern and a western portion by a dashed-line. The locations of numerous radio transmitters  16  connected by transmission lines  22  to circumferentially disposed antenna arrays or transmission devices  12  are shown throughout the test area. Antenna arrays  12  in the eastern portion of the test area were actively transmitting radio waves during the first six years of the 10-year test period (between 1992 and 1998). Those antenna arrays west of the dashed-line were inactive for several years prior to the test period. After the inspection for termite activity in 1998, the antenna arrays  12  in the western portion of the test area were actively transmitting for the last four years of the 10-year test period (between 1998 and 2002). Numerous areas of identified termite activity  24  shown in  FIGS. 2B and 2C  as shaded areas were identified by the inventors during inspections in 1998 and subsequently in 2002. As depicted in the diagrams, new termite activity was identified in those areas where antenna arrays  12  were actively transmitting while new termite activity was not found in areas with inactive antenna arrays. 
       FIG. 3  shows a diagram of antenna arrays associated with a radio transmitter and the location of wooden poles, which served as termite attractants  20  in the area of the antenna arrays  12 . Identified termite activity at the attractant  20  is shown as a shaded area. As shown in the diagram, the inventors identified a high level of termite infestation of wooden poles  20  placed along the transmission line  22 , which operationally connects a remote radio transmitter  16  to the active antenna array  12  (antenna array number  442 ). 
     As discussed earlier, antennas arrays in the eastern portion of the test area were actively transmitting whereas antennas in the western portion of the facility remained inactive during the first six years of the test. Those active antenna arrays having the best attraction for termites broadcast a frequency of about 2-30 megahertz at an intensity of about 1 to 10 kilowatts. For those antenna arrays having the best attraction of termites, the average frequency transmitted was about 9 megahertz at an average intensity of about 4 kilowatts. The antenna arrays broadcasting in the lower frequencies and lower intensities can have an effective attraction distance in excess of 100 feet from the antenna arrays. The effective distance of the termite attraction effect of the antenna arrays is believed to vary with increased radio wave frequency and intensity.  FIGS. 4A-G  and  FIGS. 5A-H  provide an indication of the termite attraction effect of the inactive and active antenna arrays  12 . Circumferentially disposed around the individual antenna arrays were wooden poles that served as an attractant  20  within the transmission area  14 . These attractant poles  20  provided a foci for the termites attracted by the antenna arrays system of the present invention and permitted the inventors to measure the effect of the transmitted radio waves. In  FIGS. 4A-G  and  FIGS. 5A-H , it can been seen that the attractant poles  20  that were disposed near active antenna arrays  12  were observed to have different amounts of termite infestation while those inactive antenna arrays  12  had reduced or no termite infestation. 
     The results of the years of testing the radio wave transmitting system  10  of the present invention demonstrated the ability of the system to attract termites by the use of radio wave transmission. The test also showed that by attracting termites to the transmitting system  10 , adjacent wooden structures could be protected from termite infestation. 
     The present invention can be employed to attract termites to an active transmitting device  12  and by doing so protect an adjacent area from termite infestation. The invention can also be employed as a method to increase the efficiency of other devices used to attract insects such as the conventional light traps, termite traps, bait stations and the like. 
     It is also within the concept of the present invention to employ the inventor&#39;s discovery of the termite-attractant ability of a radio wave transmitting system  10  to provide an electronic sweeper that can identify structures or buildings that are more susceptible to termite infestation due to the emission of attractant radio waves. 
     The discovery of the inventors can also be used to provide a device that scrambles or “masks” the emission of attractant radio waves from termite susceptible structures or buildings. 
     The inventors have also determined that the effect of radio waves on termites can be adapted to produce a high intensity electronic field at or about 60 hertz and 20 megawatts to create a repellant shield around susceptible structures. 
     The invention claimed herein has been described generically, and by reference to specific embodiments. Examples and specific features are not intended to be limiting unless so indicated above. Modifications will occur to those of skill in the art without departing from the invention, except as excluded by the claims set forth below.