Abstract:
A control agent delivery system useful for dispersing a pesticide, herbicide, fungicide or other biocide around a target or target area that is not directly accessible or that is hazardous to the user. The system includes a separable, two-part projectile containing a control agent disposed in a powder, liquid or gel dispersal medium, together with a gas-propelled, projectile launching device. A method of use of the subject system that causes the projectile to perform differently, depending upon the manner of launch, is also disclosed.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to a system that is useful for delivering a liquid, gel or powder containing a control agent to a target or target area that is hazardous or generally inaccessible, and for dispersing the control agent around the target or within the target area. More particularly, the invention relates to a system including a projectile, preferably a biodegradable, two-part capsule containing predetermined quantities of a dispersible control agent such as a pesticide, herbicide, biocide or fungicide in liquid, powder or gel form, in combination with a gas-propelled, projectile launching device. Another aspect of the invention relates to a method of use of the subject system that causes the projectile to separate differently, depending upon the orientation of the projectile relative to the direction of travel when launched. 
     2. Description of Related Art 
     Control agents such as pesticides, herbicides, biocides and fungicides are typically applied using sprayer-type applicators or aerosol propellants. When using such devices, the active ingredient, often diluted by water or another solvent, is propelled toward a target area through a spray nozzle that typically has a range of less than about 15 feet. Difficulties are often encountered, however, in using such apparatus and methods to apply control agents to targets that are outside that range, that are located high above ground or floor level, or that are situated in otherwise hazardous locations. When sprayer devices are used to apply a pesticide to the nests or hives of swarming insects, it has been observed that the disturbed insects can follow the stream of pesticide back to its source, thereby subjecting the user to a greater likelihood of suffering painful stings and dangerous allergic reactions. 
     Injection devices suitable for use in extermination applications are disclosed in U.S. Pat. Nos. 3,564,705; 5,058,312 and 5,361,533. 
     A spring powered injection device for use in trapping animals is disclosed in U.S. Pat. No. 3,340,645. 
     Projectiles propelled by munitions or compressed gas for use in riot control are disclosed in U.S. Pat. No. 3,791,303; 3,894,492; 3,901,158; 3,951,070; 5,009,164; and 5,035,183. 
     Projectiles designed for paint ball applications are disclosed in U.S. Pat. Nos. 5,254,379; 5,353,712; 5,393,054 and 5,639,526. Such projectiles are typically sufficiently durable to withstand launching without releasing the contents but will shatter or rupture upon impact with a person or object. Paint ball projectiles can be made with rigid, semi-rigid or flexible shells and can be made using materials such as linear polymers, gelatin, moldable starch and water mixtures, for example, that are substantially impervious to the substance contained inside the shell. Where polymers are used in making the shells, a photodegradable additive can be incorporated into the polymer for environmental purposes. Various structural features and manufacturing techniques can be used in making the paint ball projectiles to affect the manner in which the projectiles burst or shatter upon impact. These include scoring, etching, dimpling and otherwise varying the wall thickness of the projectiles. Substances disclosed in the foregoing patents as being deliverable through the use of such “paint ball” type projectiles include water, glycerin, glycol, paints, dyes and other coloring agents, weighting agents, starch, vegetable oil, mineral oil, smoke and tear gas. 
     Additional prior art patents identified during prosecution of a prior related application are U.S. Pat. Nos. 954,591; 1,611,533; 2,028,217; 4,476,515; 4,756,118; 4,839,985; 5,775,026; and 6,145,441. 
     U.S. Pat. Nos. 954,591 and 2,028,217 disclose explosive projectiles containing insecticide compositions. U.S. Pat. No. 1,611,533 discloses a shooting device for discharging a bead or shot of liquid insecticide. U.S. Pat. No. 4,476,515 discloses an electrostatic sprayer for pesticides. U.S. Pat. No. 4,756,118 discloses a fire ant eradication device useful for injecting vaporized liquid containing an insecticide. U.S. Pat. No. 4,839,985 discloses a nest exterminating kit including a spring-launched projectile formed with a flexible outer wall and a relatively rigid base portion which encapsulates a liquid chemical, the projectile having an air space provided to enhance the explosive effect of the chemical as the projectile impacts a desired target. U.S. Pat. No. 5,775,026 discloses an insect bait and control station. 
     U.S. Pat. No. 6,145,441 discloses a frangible payload-dispensing projectile having a dimpled spherical capsule filled with a dispersible fill material. The spherical capsule can be made from hydrophilic colloidal materials or from synthetic organic compounds, including olefinic polymers, and can contain a fill material such s powder, particles, microcapsules, etc., mixed with a high specific gravity material. 
     SUMMARY OF THE INVENTION 
     Control agents such as pesticides, herbicides and fungicides are often needed in places that are inaccessible or difficult or dangerous to reach. Such potential use sites can include, for example, commercial buildings, warehouses, attics, barns, trees, cooling towers, and the like. 
     According to the present invention, a control agent delivery system is disclosed for use in safely applying substances such as pesticides, herbicides, fungicides and other biocides to targets situated in areas that are not directly accessible or that are potentially hazardous to the user. 
     According to a preferred embodiment of the invention, a control agent delivery system is disclosed that comprises a projectile and a projectile launching device. The projectile preferably contains a substance selected from the group consisting of liquids, gels and powders, the substance comprising at least one control agent selected from the group consisting of pesticides, herbicides and fungicides. The projectile can be selectively positioned by the user prior to launch so as to cause the projectile to release the substance containing the control agent either shortly after leaving the barrel of the projectile launching device or upon impact with a more distant target, as desired. 
     According to another preferred embodiment of the invention, a projectile is disclosed that comprises an elongated, generally cylindrical, hollow body made of naturally occurring gelatin or dried animal protein, the body further comprising opposed, slidably engageable male and female sections, each section having one convex, most preferably hemispherical, closed end and one generally circular, open end, the body containing a liquid, gel or powder substance comprising at least one control agent selected from the group consisting of pesticides, herbicides, fungicides or other biocides. 
     According to another preferred embodiment of the invention, an apparatus is disclosed that comprises a projectile launching device, preferably utilizing a compressed gas source such as, for example, air, nitrogen or carbon dioxide, but most preferably carbon dioxide, as a propellant, in combination with the projectile of the invention. According to one particularly preferred embodiment of the invention, the projectile launching device and projectile are cooperatively sized and configured in such manner that they are not usable in conventional firearms or in commercially available paint ball systems. 
     According to another preferred embodiment of the invention, a method is disclosed for applying a control agent to a close-range target area. The method comprises the steps of providing a projectile as disclosed herein that contains a substance, most preferably diatomaceous earth or another similarly satisfactory material, that functions as a carrier for a control agent such as a pesticide, herbicide, fungicide or other biocide; loading the projectile into a projectile launching device with the projectile oriented so that the closed end of the female portion of the projectile is forwardly facing; directing the projectile launching device toward a target area; and actuating the projectile launching device to launch the projectile toward the target area. With the projectile oriented in this manner, propelling gasses from the projectile launching device cause the projectile to fracture into a plurality of smaller pieces within a relatively short time and distance after exiting the barrel of the device for reasons discussed in greater detail below. As a result, the substance containing the control agent is dispersed and distributed over an elongated target zone extending from about three to about 30 feet from the end of the barrel, with the broadest and most concentrated coverage occurring about 15 feet from the end of the barrel. Beneficial results are also achieved when a projectile oriented in the close-range position impacts a solid object shortly after exiting the barrel of the projectile launching device, in which case the projectile will fracture upon impact, causing dispersion of the substance containing the control agent into a cloud surrounding the point of impact. 
     According to another preferred embodiment of the invention, a method is disclosed for impacting a solid target, such as a wasp nest, at a range of up to about 30 feet or more from a projectile launching device and for dispersing a control agent in a zone or area around the target. The method preferably comprises the steps of providing a projectile as disclosed herein containing a carrier material or diluent, most preferably diatomaceous earth, and further comprising a control agent such as a pesticide, herbicide, biocide or fungicide; loading the projectile into a projectile launching device with the projectile oriented so that the closed end of the male portion of the projectile is forwardly facing, directing the projectile launching device toward a target, and actuating the projectile launching device to launch the projectile toward the target. With the projectile oriented in this manner, it will desirably continue along a trajectory dictated by ballistic factors such as its launch velocity, cross-sectional area and geometry, air resistance and the physical state of the contained substance, until such time as the projectile impacts the target. Impact with the target, or with another solid object proximal to the target, desirably fractures or shatters the projectile, causing the control agent to disperse and thereby creating a cloud of the control agent around the target. Most preferably, where the target is a solid object such as a wasp or other insect nest, the projectile will contact the target with sufficient force to actually disengage it from its support or point of attachment to a structure and cause it to fall, while simultaneously coating both the nest and insects located on or near the nest with the control agent. Even where the nest is not contacted directly by the projectile, any “near-miss” that causes the projectile to impact another nearby solid object should likewise produce a cloud of the control agent in the vicinity of the nest. 
     If desired, color coding or other indicia can be provided to help the user readily distinguish between the male and female ends of the projectile, thereby facilitating loading of the projectile into the projectile launching device in such manner as to produce the intended dispersion effect. This can be done, for example, by providing identical projectiles for use in both methods of the invention, with adequate instructions informing the user as to which end should be forwardly directed for a particular application, or by providing differently marked capsules for the different applications, again with adequate instructions regarding which to use and how to load for each method of application. 
     According to another preferred embodiment of the invention, a method is disclosed for contacting or treating fauna or flora, especially pests, fungi and the like, situated in hard-to-reach or otherwise hazardous locations with a control agent through the use of a projectile as disclosed herein propelled by a gas-powered launching device from a remote location toward the intended use site. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The apparatus of the invention is further described and explained in relation to the following figures of the drawings wherein: 
     FIG. 1 is a an enlarged perspective view, partially broken away and partially in section, that exaggerates for illustrative purposes principal structural elements of a preferred projectile of the invention; 
     FIG. 2 is a longitudinally exploded perspective view of the capsule portion of the projectile of FIG. 1, without the substance containing the control agent; 
     FIG. 3 is a simplified perspective view of the control agent delivery system of the invention being used according to one preferred embodiment of the inventive method, wherein the projectile fractures shortly after exiting the barrel of the projectile launching device; 
     FIG. 4 is a simplified perspective view of the control agent delivery system of the invention being used according to another preferred embodiment of the inventive method, wherein the projectile impacts an insect nest suspended from an overhead support located approximately thirty feet from the barrel of the projectile launching device; 
     FIG. 5 is a enlarged detail view, partially in section, illustrating a preferred projectile of the invention when oriented according to the method shown and described in relation to FIG. 3 as the projectile travels through the barrel of the projectile launching device, and depicting the manner in which the propelling gas acts on the projectile while inside the barrel; and 
     FIG. 6 is a enlarged detail view, partially in section, illustrating a preferred projectile of the invention when oriented according to the method shown and described in relation to FIG. 4 as the projectile travels through the barrel of the projectile launching device, and depicting the manner in which the propelling gas acts on the projectile while inside the barrel. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring to FIGS. 1 and 2, projectile  10  preferably comprises two opposed and slidably engageable sections, including male body section  12  and female cap section  14 . The physical configuration is similar to that of commercially available double blind (DB) capsules, although the moisture content is preferably within defined ranges as described below. Each section  12 ,  14  preferably has a cylindrical sidewall section  16 ,  18 ; one convex, preferably hemispherical, closed end  24 ,  26 ; and one open end preferably defined by substantially circular edge  20 ,  22 , respectively. Projectiles  10  having substantially flatter ends can exhibit a more erratic flight path. Cap section  12  is desirably slightly longer and more slender than cap section  14 . When assembled as shown in FIG. 1, with a substance comprising a control agent  28 , preferably selected from the group consisting of a pesticide, herbicide or fungicide, disposed inside projectile  10 , edge  20  of body section  12  preferably slides inwardly of edge  22  of cap section  14  so that a portion of the outside surface of sidewall section  16  is closely adjacent to a portion of the inwardly facing surface of sidewall section  18 . Referring again to FIGS. 1-2, body section  12  preferably further comprises an annular groove  30  that cooperates with annular detent  32  of cap section  14  so that the body and cap sections can be snapped into frictional engagement in the position shown in FIG. 1 to produce projectile  10 . Control agent  28  is preferably loaded into projectile  10  prior to assembly of body and cap sections  12 ,  14 , although commercially available injection systems can also be used, particularly with liquid or gel carriers, to fill projectile  10  after assembly of body and cap sections  12 ,  14 . 
     Body and cap sections  12 ,  14  of projectile  10  are preferably made of a destructively deformable material such as dried animal protein, most preferably in the form of a natural gelatin. Controlling the moisture content of the gelatin within desired ranges is believed to be significant for achieving optimal results with the invention. Gelatin capsules of the type frequently used for pharmaceutical applications typically have moisture contents ranging from about 20 to about 30 weight percent by weight of the capsule and not including the weight of the contained medicament. However, for reasons discussed in greater detail below in relation to the system and method of the invention, body and cap sections  12 ,  14  having a moisture content ranging from about 5 to about 20 weight percent, and most preferably from about 5 to about 15 weight percent, at the time of use are preferred. Projectiles  10  wherein the body and cap sections  12 ,  14  have moisture contents greater than about 20 weight percent tend to deform rather than fracture or shatter as desired during use. Conversely, projectiles  10  wherein the body and cap sections  12 ,  14  have moisture contents less than about 5 weight percent can fracture or shatter prematurely. According to one particularly preferred embodiment of the invention, projectile  10  is made with body and cap sections  12 ,  14  having a moisture content ranging from about 15 to about 18 weight percent. When projectile  10  is filled with a dry powdered or granular substance as discussed below, some moisture will migrate from the gelatin into the powder, thereby reducing the moisture content of the gelatin to, for example, about 10 weight percent. Depending upon conditions of storage and the elapsed time between manufacturing and use, the moisture content can be further affected by the ambient temperature and humidity to further decrease or, in some cases increase, the moisture content of the gelatin. Most preferably, the moisture content of the gelatin in body and cap sections  12 ,  14  will be about 10 weight percent±about 5 weight percent at the time of use. Commercially available desiccants or humectants can be provided in or with projectiles  10  where needed to provide suitable moisture contents at the time of use. Where the substance containing control agent  28  is a liquid or gel, non-aqueous carriers are preferred to prevent moisture from migrating into the walls of body and cap sections  12 ,  14 . Alternatively, it can be preferable to coat the inside walls of body and cap sections  12 ,  14  with a hydrophobic material to prevent moisture migration in such cases. 
     In addition to natural gelatin, other similarly effective materials, particularly grafted starch and some polymeric materials, can also be used in making body and cap sections  12 ,  14  of projectile  10 , provided that such materials are capable of carrying control agent  28 , are tough enough to withstand launching, and are also brittle enough to destructively deform or shatter upon impact with an object. Generally speaking, materials used in making body and cap sections  12 ,  14  of projectiles  10  will be in a near-crystalline state rather than in an amorphous state at the time of use so as to promote fracturing or shattering during use in accordance with the methods of the invention. Additives that promote photodegradation or biodegradation of the polymer following use can also be included in the formulations used to make body and cap sections  12 ,  14  where desired. The use of colorants or other visible indicia in or on at least one of body and cap sections  12 ,  14  can also help the user readily distinguish between the body and cap sections  12 ,  14  of projectile  10  when loading projectile  10  into the projectile launching device for use in practicing the method of the invention as described below. 
     Particularly preferred control agents  28  for use in the invention include pesticides, herbicides and fungicides at concentrations consistent with those used in conventional applicators. It will also be understood and appreciated upon reading this disclosure that other control agents such as antimicrobial agents, algaecides, animal control agents, spill control agents and the like can also be used within the system and method of the invention, and that dosage rates can vary depending upon the intended application and upon the size and nature of the target or target area. Examples of pesticides that can be utilized as control agents in the present invention include pyrethrin, piperonyl butoxide, permethrin, chlorpyrifos, propoxur, bacillus thuringiensis, hydromethylnon, fipronil and other similarly effective compounds. Examples of herbicides that can be utilized as control agents in the present invention include bromacil, dicamba, glyphosate and other similarly effective compounds. Examples of fungicides that can be utilized as control agents in the present invention include benomyl, cyproconazole, imazalil and other similarly effective compounds. 
     Control agent  28  is preferably provided in combination with a carrier substance that can be in liquid, solid or gel form, and if a solid, is preferably a finely divided powder or granular material. In producing projectiles  10 , the inert carrier material, filler or diluent can be used to increase the weight or volume of material inside the projectile as desired. Where the carrier substance is a powder or granular solid, control agent  28  is preferably coated or adsorbed onto the surface of the carrier particles in such manner that control agent  28  retains its efficacy as an active ingredient. Preferred carrier materials for particular systems can comprise, for example, diatomaceous earth, which is preferred, fumed silica, corn starch, talc, ground walnut shells, and the like. Where the carrier material is a liquid or gel, for example a glycol, control agent  28  is desirably soluble or miscible in the carrier. When using a liquid carrier, a truer flight path for projectile  10  is achieved by minimizing any unfilled space inside projectile  10  and by incorporating a dispersible, finely divided, particulate material such as an inert powder into the liquid. Other components such as pest attractants, including for example, feed attractants and pheromones, can also be included together with control agent  28  inside projectile  10  if desired. 
     Referring to FIGS. 3 and 4, control agent delivery system  40  of the invention preferably comprises projectile  10 , as described above, in combination with projectile launching device  42 . Projectile launching device  42  can have any one of many different configurations such as, for example, a simulated rifle or pistol, or any other similarly effective apparatus having a launch tube or barrel with an elongated bore  44  and a source of pressurized gas  48  that can be activated to propel projectile  10  from the bore at an acceptable velocity and trajectory. The diameter of bore  44  is preferably slightly greater than the outside diameter of cap portion  14  of projectile  10  to reduce the tendency of propelling gas  48  to blow past projectile  10  during launch. In FIGS. 3 and 4, projectile launching device  42 , partially broken away, is configured similarly to the muzzle of a conventional gas-operated pistol that, when actuated, directs the pressurized, propelling gas  48  through bore  44 , which is preferably smooth. Projectile launching device  42  is also desirably equipped with a sighting device  46  to assist a user in aiming projectile  10  toward a target. Propelling gas stream  48 , preferably carbon dioxide, nitrogen or air, and most preferably carbon dioxide, is discharged from a pressurized gas source that is controlled by conventional means so a gas pulse of desired duration is released and directed against projectile  10  inside bore  44  when projectile launching device  42  is triggered or otherwise activated by a user. Preferred sources of pressurized gas for use as propelling gas stream  48  include pre-packaged cartridges or canisters that are lightweight and yet contain a sufficient quantity of compressed gas to launch a series of projectiles  10  at an acceptable velocity without resupply. 
     Projectile launching device  42  is preferably easily maneuverable so as to facilitate variation or adjustment of the launch direction and trajectory by the user. FIG. 3 depicts projectile  10  being propelled in the direction shown by arrow  50  toward a target zone or area  54  that is proximal to projectile launching device  42  in accordance with one embodiment of the inventive method. FIG. 4 depicts projectile  10  being propelled toward a more distal target  58  in accordance with another embodiment of the inventive method. 
     Referring to FIGS. 3 and 5, whenever control agent delivery system  40  is intended for use in delivering a control agent  28  as previously described to a target area  54  that extends over a greater area than would typically be associated with a specific target, such as an insect nest, projectile  10  is selectively loaded into projectile launching device  42  with the closed end of cap section  14  facing toward the target. Projectile launching device  42  is most preferably positioned approximately 15 feet from the center of the target area prior to launching projectile  10 . When propelling gas stream  48 , most preferably carbon dioxide, is released from a pressurized gas source connected to projectile launching device  42 , projectile  10  is forced out the barrel toward target area  54 . As the projectile travels through bore  68  of barrel  44 , propelling gas stream  48  flows around the closed end of body section  12 , as shown by stream lines  72 , and beneath edge  22  of cap section  14 . This causes edge  22  to flare outwardly against sidewall  74  of bore  68 , providing an annular seal  76  against sidewall  74  as the projectile travels down barrel  44  in the direction shown by arrow  70  in FIG.  5 . The frictional engagement between body section  12  and cap section  14  at annular detent  32 , in cooperation with the confined space for radial expansion that is afforded by sidewall  74  of bore  68 , prevents the sections from separating before exiting the barrel. If the material used in making sections  12 ,  14  contains less than about five weight percent moisture, the walls of sections  12 ,  14  can shatter inside barrel  44 , causing propelling gas stream  48  to actually blow through the projectile and out the barrel, scattering the control agent in a cloud around the user rather than in the desired target zone  54  as shown in FIG.  3 . Desirably, projectile  10  will exhibit fractures  38  upon exiting barrel  44 , followed by complete shattering into fragments  52  at a distance of about 1 to 5 feet, and most preferably about 3 feet, after exiting the barrel. Where the moisture content of body and cap sections  12 ,  14 , respectively, ranges between about five and about 15 weight percent moisture, projectile  10  will typically shatter as depicted diagrammatically in FIG. 3, and control agent  28  will disperse in a plume or pattern extending up to about 30 feet from the projectile launching device, with the widest spread and heaviest concentration of control agent  28  falling approximately 15 to 18 feet from projectile launching device  42 . Where the moisture content of projectile  10  exceeds about 20 weight percent, projectile  10  may simply deform and not achieve the desired dispersion of control agent  28 . 
     Referring to FIGS. 4 and 6, whenever control agent delivery system  40  is intended for use in delivering a control agent  28  as previously described to a specific target such as insect nest  58 , projectile  10  is selectively loaded into projectile launching device  42  with the closed end of body section  12  facing toward the target. When propelling gas stream  48 , most preferably carbon dioxide, is released from a pressurized gas source connected to projectile launching device  42 , projectile  10  is forced through and out of barrel  44  toward target  58 . It should be appreciated that the annular gap between the outside of cap section  14  and sidewall  74  of bore  68  inside barrel  44  is exaggerated for illustrative purposes in FIG.  6 . As the projectile travels through bore  68  of barrel  44  in the direction shown by arrow  70 , propelling gas stream  48  causes the projectile to gain sufficient speed to reach a target  58  up to about 30 feet away from projectile launching device  42 . Although the trajectory is depicted as a straight line  56  in FIG. 4, where control agent  28  is provided with a dry particulate carrier material, it is likely that the flight path of projectile  10  will approximate a helical spiral of expanding diameter as projectile  10  travels from projectile launching device  42  to a target  58  disposed about 30 feet away. Most preferably, the diameter of the helical spiral will not exceed about 18 to 24 inches over a distance of about 30 feet. If the material used in making sections  12 ,  14  contains from about 5 to about 15 weight percent moisture, projectile  10  will not shatter during flight but will preferably shatter into fragments  52  upon impact with target  58  or another solid object situated nearby, causing control agent  28  to disperse in a cloud surrounding the target. Projectile  10  will desirably have sufficient force upon impact to detach a nest such as target  58  from its point of attachment  60  to support member  62  as shown. Where the moisture content of projectile  10  is greater than about 20 weight percent, projectile  10  is unlikely to fracture and shatter upon impact with a solid object. 
     It should be understood that the trajectories and distances as disclosed herein, although based on actual tests, are approximate and are dependent upon many interrelated factors including without limitation the force and duration of the propelling gas stream, the length and diameter of the bore of the projectile launching device, the weight and dimensions, including wall thickness, of the projectile, the nature and moisture content of the material used in making the projectile, the physical state and density of the material contained inside the projectile, the angular positions of the barrel and target, atmospheric conditions, and the like. Nevertheless, applicants have learned, and it is now apparent from this disclosure, that significantly different beneficial results are achievable through use of like projectiles and the same projectile launching device in the control agent delivery system of the invention dependent upon whether the projectile is loaded with the body or cap section facing the target or target area. Target zones such as an area over which a control agent is to be scattered or dispersed are best covered when the projectile is loaded with the female section forward. Conversely, more distant, specific targets are best treated by loading the projectile with the male end forwardly facing. When using this mode or embodiment of practicing the invention, hazardous targets such as insect nests can be reached and treated while the user remains a safe distance away. Target distances as great as up to about 45 feet from the projectile launching device may be reachable practicing this embodiment of the invention under some circumstances, although aiming accuracy may be reduced substantially at distances over about 30 feet, and aiming distances ranging from about 25 to about 30 feet are preferred. 
     Projectiles  10  as disclosed herein are most preferably made with a length of about 0.67 inches and a diameter of about 0.38 inches. If desired, however, both the length and diameter can vary, provided that ratio of length to diameter is controlled within a range of about 1.58 to about 1.94. This slightly elongated, tubular shape is believed to promote separation and/or shattering of projectile  10  upon impact with a solid object. Projectiles  10  having a higher length-to-diameter ratio can tend to wobble during flight, and more spherical projectiles having a lower ratio can be more prone to veering off in one direction from the aiming point during flight. If desired for safety or other reasons, the caliber of projectile  10  and barrel  44  of projectile launching device  42  can be selected so as to avoid interchangeability with conventional ammunition, paint balls or riot-control projectiles. The filled weight of projectiles  10  made according to the invention is preferably greater than about 0.35 grams, and preferably ranges between about 0.5 and about 1 gram per capsule. Filled weights greater than about 1 gram can increase the likelihood of unintentional glass breakage during use. 
     Projectiles  10  as disclosed herein can be safely used around building windows without fear of breakage when propelled from projectile launching device  42  by conventional CO 2  cartridges of the type used, for example, in pellet guns. The preferred launch velocity of projectiles  10  weighing from about 0.5 to about 1.0 grams is about 600 feet per second. To avoid breaking window glass at close range, the launch velocity for projectiles  10  should not exceed about 1000 feet per second. Where the use of projectile launching devices  42  having an outside configuration similar to that of a conventional firearm is deemed socially or politically undesirable, other configurations having an elongated tubular bore and any suitable mechanism for controlling the release of pressurized gas into the bore behind the projectile can likewise be used within the scope of the invention. 
     According to another method of the invention, fauna or flora situated in hard-to-reach or otherwise hazardous locations are contacted and treated for organisms such as pests, fungi and the like, with a control agent such as a pesticide, fungicide, herbicide or biocide by the use of a projectile as disclosed herein propelled by a gas-powered launching device from a remote location toward the intended use site. 
     Using system  40  and the methods of the invention, control agents  28  are successfully delivered and applied to target areas and targets at distances ranging from as little as about 1 to 3 feet, up to distances of about 45 feet or more from the user. The system and method of the invention are useful for treating areas that are dangerous or not otherwise accessible using known conventional applicator means for like agents. 
     Other alterations and modifications of the invention will likewise become apparent to those of ordinary skill in the art upon reading the present disclosure, and it is intended that the scope of the invention disclosed herein be limited only by the broadest interpretation of the appended claims to which the inventors are legally entitled.