Abstract:
A plant attachment device and a method for killing obnoxious weeds that includes the step of cutting a stem of an obnoxious weed to leave a cut end extending from the ground to enable a container having an herbicide therein to be placed over the cut end of the stem and members thereon for supporting the herbicide carrier on the cut weed stem to hold the herbicide proximate the cut end to allows the herbicide sufficient time to penetrate into the tissue of the weed to cause the weed to die.

Description:
This Appln claims the benefit of Provisional No. 60/114,845 filed Jan. 6, 1999. 
    
    
     FIELD OF THE INVENTION 
     This invention relates generally to plant control and more specifically to an apparatus and method for killing stubborn weeds, vines and small trees. 
     BACKGROUND OF THE INVENTION 
     The concept of chemical destruction of obnoxious weeds is well known in the art. Typically, a herbicide is sprayed on the leaves and stem of a weed to kill it. Oftentimes, weeds with deep roots require repeated applications of the herbicide before they die. This can lead to large expenditures for herbicides, as well as excessive herbicide that could be destructive to neighboring plants. In addition many herbicides require pre-application mixing procedures for activation or dilution. These procedures can increase the time necessary to effectively apply the herbicide, as well as creating a possible health hazard. 
     Another difficulty with traditionally applied herbicides is that rain can wash the herbicide off the leaves and stem of the plant before the herbicide can penetrate into and destroy the plant. Depending upon the type of herbicide, this could have damaging effects upon the surrounding plants. Further, many weeds are unfortunately perennial, and the use of traditional herbicides to control them may not prevent an annual appearance by the offending weed. 
     One of the most common methods of killing obnoxious weeds is to spray the leaves of the plant with a herbicide. In order to enhance the effectiveness of the herbicide and to prevent destruction of useful plants around the obnoxious weed one can place a shroud or some confinement member over the plant. Such an item is shown in the Dickison U.S. Pat. No. 2,841,923. Dickison uses a cup like member that is placed over the leaves of the plant so that the herbicide can be sprayed directly to the leaves of the plant and the environment around the plant. 
     The present invention provides an insitu herbicide carrier mechanism for those particularly stubborn weeds without the use of large cumbersome shrouds that envelope the leaves of the plant. The present invention can come ready-to-use so as to not require premixing and thus minimize contact between user and herbicide. In addition since the herbicide is not airborne one also minimizes chances of inhalation of the herbicide. With the present invention the herbicide is held in confinement for direct transfer to a cut stem of an obnoxious weed. The carrier mechanism, while delivering the herbicide to the plant, also provides a protective cover to prevent rain from washing the herbicide away from the plant. 
     The present invention is particularly useful for destroying perennial type weeds that require eradicating by killing the roots of the weed as the present invention maintains a supply of herbicide in direct contact with a weed stem for an extended period of time to allow the herbicide to penetrate into the roots of the weed and kill it. 
     BRIEF DESCRIPTION OF THE PRIOR ART 
     U.S. Pat. No. 2,841,923 discloses a spraying device with a cup shaped member that is placed over the plant before spraying the herbicide on the plant. 
     U.S. Pat. No. 3,899,100 displays a packing tube with at least one removable tube with the end cap having segments that deflect inward to insert objects therein. 
     U.S. Pat. No. 4,199,896 discloses a machine mounted boom sprayer that has a conical hood to limit the spray pattern. 
     U.S. Pat. No. 4,223,477 discloses a house plant sprayer shroud comprising a plastic bag to retain the insecticide proximate the plant. 
     U.S. Pat. No. 4,328,904 discloses a spill-proof container with flexible closures that flex inward to allow for insertion of articles therein. 
     U.S. Pat. No. 5,593,059 discloses a weather resistant newspaper delivery receptacle having a closure with end caps having flaps that fold inward to insert a newspaper or the like therein. 
     U.S. Pat. No. 5,676,990 discloses a method of food article dipping and wiping device wherein a set of flaps contact the article to remove excess condiment. 
     Great Britain patent 718,042 discloses 
     SUMMARY OF INVENTION 
     Briefly, the present invention comprises a plant attachment device including a herbicide carrier with a herbicide maintainable therein with the herbicide carrier having a penetrable cover to permit insertion of a cut stem of an obnoxious weed into the herbicide in the herbicide carrier where the herbicide can be allowed to penetrate though and into the plant stem and into the roots of the plant to kill the plant. The plant attachment device grips the plant stem to retain the herbicide carrier in place and also forms a protective cap over the cut weed stem to prevent rain from washing the herbicide away from the plant as well as to prevent the herbicide carrier from accidentally falling off the stem. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of the herbicide carrier of the present invention; 
     FIG. 2 is a cross-sectional view of the herbicide carrier of FIG. 1; 
     FIG. 3 is a side view showing the stem of an obnoxious weed being cut with a knife; 
     FIG. 4 is an elevated view of the cut stem of the weed shown in FIG. 3; 
     FIG. 5 shows the herbicide carrier of FIG. 1 located on the cut stem; and 
     FIG. 6 shows a sectional view of the herbicide located on the cut stem shown in FIG.  5 . 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     FIG. 1 shows herbicide carrier  10  comprising a cylindrical shell having a closed end  10   a  and a capped end  10   b  having a penetrable cover comprising a set of pie-shaped flaps  11 ,  12 ,  13 ,  14 ,  15 ,  16 ,  17 , and  18  that extend toward a central point  40  of the carrier  10 . The pie-shaped flaps are cantilevered radially inward from carrier  10  and are sufficiently resilient so as to maintain their extended postion during handling and shipping thereby inhibiting accidental herbicide disengorgement of the herbicide therein. The flaps have sufficiently flexible to allow the cut stem of a weed to penetrate through the flaps. 
     FIG. 2 shows a cross-sectional view of herbicide carrier  10  comprising a cup shaped rigid housing  35  having a closed end  10   a  and an open end covered with a set of resilient pie-shaped flaps  11 - 18  that cantilever out to a convergence point to form a closure over the end of the housing  35   a . Housing  35   a  is preferable made from a rigid material such as a rigid polymer plastic so that the handling or application of the carrier to a plant stem does not result in the herbicide accidentally being squeezed out. However, other materials are within the scope of the present invention such as biodegradable materials that will disintegrate over an extended period of time which is longer than the time taken to kill the obnoxious weed An example of such a biodegradable material is a paper material. With a biodegradable carrier one need not retrieve the housing once the plant is dead. 
     Located within housing  10   a  is a chamber  20 . A portion of chamber  20 , which is identified by reference numeral  21   a , is void of herbicide and a further portion of chamber  20 , which is identified by reference numeral  20   b , has a herbicide  21  located therein. In the embodiment shown, the herbicide  21  is suspended in a viscous medium to maintain the herbicide in a non flowing condition within the herbicide carrier  10 . That is, the herbicide does not flow out of the herbicide carrier if the carrier is tipped upside down. The viscous medium can be any material that is sufficiently viscous as to be non flowing and is compatible with the herbicide. Typically, a suitable viscous material is silicone or the like. However, if the herbicide is itself in a viscous state one would need no viscous carrier. In the embodiment shown the herbicide is shown partially filling carrier  10 , and is in a ready-to-use condition. That is chamber  21   a  provides an expansion chamber for the herbicide  21  to flow into as a weed stem is inserted into the herbicide carrier. Pie-shaped flaps  12  and  16  which form part of a penetrable cover that can retain the housing on a weed stem are shown in their normally fully closed position to prevent any of the herbicide  21  from escaping the carrier  10  during normal handling of the herbicide. 
     While the cover flaps  11 - 18  are shown performing the dual function of protecting the herbicide and engaging the plant, the plant engagement member need not be the cover but another member that engages the plant to hold the herbicide carrier in place. For example, a spike attached to housing  10  and located in the chamber  20  could project toward the open end so that the spike could be impaled on the cut end of the stem and thereby hold the herbicide carrier in kill postion on the obnoxious weed. 
     To illustrate the method of the invention reference should be made to FIG. 3, which shows a particular obnoxious weed  30  with the stem of the weed being cut by a garden tool  31  to produce a cut stem which is shown in FIG.  4 . Weed  30  is the type of stubborn weed that cannot be destroyed by applying herbicide to the leaves, or is of the type that requires repeated applications of a herbicide in order to destroy the weed. Obnoxious weeds of this type can generally be destroyed with extended applications of herbicide to the plant stem which allows the herbicide to penetrate into the roots of the plant, which may be several feet in length. The stem illustrated in FIG. 4 has a fresh cut on the end thereof and is in a prime condition to absorb the herbicide therein. Once cut, one axially aligns the carrier  10  and the cut stem before inserting the stem though the flexible cover by forcing the carrier down onto the cut stem. 
     FIG. 5 shows the herbicide carrier  10  of the present invention located on the end of stem  30  with the closed end  10   a  of the herbicide carrier  10  facing upward and the pie shaped flaps engaging the stem  30 . In order to place the housing  10   a  on the stem the user grasps the exterior of the housing  10   a  in his or her fingers and places the pie shaped flaps  11 - 18  proximate the weed stem and pushes the housing  10   a  downward. The resilient flaps flex inward to allow penetration of the weed stem and at the same time the resiliency of the flaps supports the herbicide carrier on the stem of the plant. 
     FIG. 6 shows a more detailed cross-sectional view of herbicide carrier  10  located on the cut stem of plant  30  with the herbicide  21  being held in proximity to cut stem  30  by the flaps  11 - 18  which are bent around the stem of the plant. With the flaps maintaining a supporting relationship to the herbicide carrier the herbicide carrier can continue to deliver herbicide  21  to the weed stem  30  so that the roots of the weed absorb the herbicide thus eventually killing the entire weed. As the flaps  11 - 18  maintain the herbicide carrier on the stem the herbicide  21  can be delivered to the stem under all weather conditions. That is if it should rain the herbicide carrier forms a rain cap to prevent water from contacting the cut end of the stem. In addition, the viscous medium can help maintain the herbicide in the carrier as well as maintain a path for the herbicide to penetrate into the roots of the weed and thus kill the weed. 
     The present invention is particularly useful with those type of weeds such as poison ivy which generally cause a rash when the person comes into contact with the plant Normally the cutting of a poison ivy plant is ineffective in killing the poison ivy. With the present invention one can cut the poison ivy plant using a tool so that the person does not come into direct contact with the irritating chemicals of the poison ivy. Once cut a person can insert the herbicide carrier onto the cut stem without having to come into direct contact with the plant. Consequently, the present invention provides an effective method for eliminating those hard to kill weeds which are also harmful to touch.