System for uprooting aquatic plants
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to devices for removing aquatic plants from lakes and ponds, and more particularly to a device and method for uprooting aquatic plants using a plurality of water jets directed into the soil bearing the plant roots. 
     2. Description of the Prior Art 
     A frequent problem of lakefront property owners is proliferation of choking underwater plants as the summer progresses. While aquatic plants serve an admittedly useful purpose with respect to the environmental balance of a body of water, over production of aquatic plants adjacent a property owner&#39;s shore impedes recreational use of the lake. The problem is more than just aesthetics: wading is unpleasant, boating can be impaired as propellers get caught in the plant beds and swimming may become impossible in plant infested areas. Left unchecked, it is even possible over a number of years for a bay of a lake or pond to become marsh, as the aquatic plants choke it off. 
     Accordingly, riparian property owners frequently must battle aquatic plant growth in order to preserve and enhance their property value and secure pleasurable enjoyment of the water. A number of techniques are available of varying cost, environmental hazard, and laboriousness; some are regulated by state law, requiring a permit before plant removal is attempted. Generally speaking, the common solutions to rid an area of undesirable aquatic plants are: harvest them, kill them, uproot them, shade them, trample them, introduce fish that eat them, or dredge the area and in so doing remove them. 
     Harvesting by machine requires very expensive equipment and usually requires permits and state agency supervision. Harvesting cuts the plants below the water surface and captures the plant cuttings on a moving conveyer belt. Many of the plant cuttings escape the conveyer belt and either float downwind to a beach or else sink, depending upon the type of plants. In either case, some of the clippings can re-root and start another plant. And, of course, the plants that were cut will continue to grow, only to be harvested again in an endless cycle. 
     Harvesting by hand using a rake and cutting tool has the same advantages of machine harvesting, in that plant clippings are removed. Of course, without a capturing device for the clippings, the plant cuttings will disperse and likely re-root, only to be thereafter cut another day. Again, the plants which have been cut continue to grow. 
     Uprooting the aquatic plants by hand raking is not effective at removing plants by the roots, and the process is far too laborious to be practical. Uprooting plants by hand pulling is slow, tedious, and extremely laborious. 
     Certain chemicals are effective, selective killers of aquatic plants. However, there are use restrictions, and permits are required. Chemicals can contaminate the environment, enter the food chain (including game fish), injure wildlife, restrict swimming and limit water use for drinking, lawn sprinkling and livestock watering. Because of the permits and regulations associated with chemicals, the average homeowner is unlikely to be able to purchase and use them. Of course, once the chemical has become neutralized, the plants will return and proliferate. 
     Shading aquatic plants until they die from lack of sunlight by means of opaque plastic sheets requires considerable installation time, and a considerable amount of plastic sheeting. Usually a permit is required, and the plastic sheets will interfere with recreational use of the water. 
     Trampling aquatic plants is effective in those select areas where considerable human traffic is common, such as public beach areas. The typical homeowner will not have sufficient activity to make this a viable reality. 
     Aquatic plant eating fish, such as the grass carp or white amur, are regulated for usage in many states. Management of the fish population of a body of water usually requires professional assistance and can be expensive. However, when properly managed, plant eating fish can be very effective in controlling aquatic plants. 
     Dredging requires specialized equipment which is professionally operated. While dredging is very effective, the effects associated with soil removal can adversely affect the lake environment, so this technique is usually highly regulated by state agencies; and the cost is extremely high. 
     While the foregoing techniques each offer some relief from the problems associated with aquatic plants, none is truly well suited for use by a private riparian property owner. Accordingly, what is needed is a simple, easy and effective device for ridding an area of lake bottom of undesirable aquatic plants, which is truly usable by a homeowner. 
     SUMMARY OF THE INVENTION 
     The present invention is a device, particularly well suited for use by a lakefront homeowner, which is structured to remove aquatic plants by sending a plurality of water jets into the soil, thereby causing uprooting of the plants. 
     The aquatic plant uprooter according to the present invention is composed of a hollow handle, a hollow discharge member connected at right angles to the handle, and a plurality of regularly spaced apart nozzles connected to the discharge member. A flexible hose connects a distal end of the handle to a water pump. The handle serves as a fluidic conduit for water from the pump to flow into the discharge member, which in turn, serves as a fluidic conduit for water from the handle to flow into the nozzles. The nozzles are structured, located and mutually spaced so that a jet of water emerges from each, which collectively disturbs the soil of a body of water so as to uproot aquatic plants in a swath across the discharge member by loosening their anchorage in the soil. The soil-freed plants may be directly accumulated in a collection net attached to the handle and discharge member, or may be collected by use of a separate rake-net system. 
     Accordingly, it is an object of the present invention to provide an aquatic plant uprooter which utilizes jets of water to eliminate, or at least greatly weaken, anchorage of the plant roots in relation to the soil, thereby freeing the plant from the lakebottom. 
     It is an additional object of the present invention to provide an aquatic plant uprooter which uses jets of water to uproot plants and is usable by a lakefront homeowner. 
     It is another object of the present invention to provide an aquatic plant uprooter which uses jets of water to uproot plants and further includes a net attachment to collect the plants as they are uprooted. 
     It is still another object of the present invention to provide an aquatic plant uprooter which uses jets of water to uproot plants and which is structured for being pulled or pushed across the lakebottom by a user. 
     It is a further object of the present invention to provide an aquatic plant uprooter which uses jets of water to uproot plants and which is inexpensive, efficient and effective for ridding a lake bottom of unwanted aquatic plants. 
     It is yet an additional object of the present invention to provide a rake-net device which permits a user to easily and effectively accumulate uprooted or harvested aquatic plant material from a body of water. 
     These, and additional objects, advantages, features and benefits of the present invention will become apparent from the following specification. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of the aquatic plant uprooter according to the present invention shown in operation by a lakefront homeowner. 
     FIG. 2 is a perspective view of the aquatic plant uprooter according to the present invention. 
     FIG. 2A is a detail perspective view of a strap for connecting handle and discharge member components of the present invention. 
     FIG. 3 is a detail, fragmentary, partly sectional side view of the discharge member of the aquatic plant uprooter designed primarily for a pull mode of operation. 
     FIG. 4 is a detail, fragmentary, partly sectional side view of the discharge member of a variation of the aquatic plant uprooter which permits both push and pull modes of operation. 
     FIG. 5 is a detail, fragmentary, partly sectional front view of the aquatic plant uprooter shown in FIG. 4. 
     FIG. 6 is a side view of the aquatic plant uprooter according to the present invention, shown in operation adjacent a lake bottom in the process of uprooting aquatic plants. 
     FIG. 7 is a perspective view of the aquatic plant uprooter according to the present invention, showing further a collection net for collecting uprooted aquatic plants. 
     FIG. 8 is a detail, fragmentary, partly sectional side view of the discharge member of the variation of the aquatic plant uprooter, seen along lines 8--8 in FIG. 7. 
     FIG. 9 is a perspective view of a rake-net device having a collection net for collecting uprooted or harvested aquatic plants. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Of all available methods of aquatic plant control, uprooting is preferred, as there is a minimum of ecological damage, growth is prevented, and regrowth can happen only in the event entirely new plants sprout. However, the exertion to manually uproot plants by extracting them from undisturbed soil is far too extreme to be practical for riparian homeowners. To solve this problem, the present invention is a device which uproots aquatic plants by use of water jets. According to the present invention, plants are uprooted by loss of supporting soil for the roots, resulting in separation of the plant from the soil. 
     Referring now to the Drawing, FIG. 1 shows the aquatic plant uprooter 10 according to the present invention being used by an individual, in this case a riparian homeowner. It will be seen from the depiction that the aquatic plant uprooter 10 is composed of a handle 12 and a discharge member 14 connected perpendicularly at its middle to the forward end of the handle 12 by means of a saddle shaped connector 12a. A plurality of nozzles 18 are provided in a row aligned parallel with the cylindrical axis of the discharge member 14, being located thereon so as to be directed downwardly toward the lake bottom 20 when the handle 12 is held at an operational angle by a user of about 35 to 45 degrees relative to the lake bottom, as shown in FIG. 1. In this regard, the handle includes a hand grip portion 12b for being held by the user which is oriented generally parallel to the water surface when the handle 12 is at the operational angle. 
     Both the handle 12 and the discharge member 14 are hollow, forming conjoining closed fluidic conduits for conducting water under pressure from the distal end 22 of the handle 12 to the nozzles 18. In this regard, it is preferred for these components to be of cylindrical cross-section. While circular cross-sections are preferred, it is also permissible for the discharge member 14 to be of an elliptical cross-section, with the nozzles located on a flatter portion of the surface curvature. An elliptical cross-section can have an advantage with respect to the ability for the discharge member to rest upon the soil rather than tending to bury into it during operation, as might happen with narrow circularly cross-sectioned discharge members. The handle and discharge member are constructed of a durable, lightweight, noncorrosive material that can withstand operation internal fluid pressures of around 20 to 60 p.s.i., such as for instance PVC. In order that the handle be rigidly affixed to the discharge member, it is preferred for the handle 12 to interconnect with the discharge member 14 by means of the saddle shaped joint 12a. A tee joint or other such joint could be substituted for the saddle shaped joint, if strongly constructed. 
     A weight member 34 is connected with the discharge member 14 in order to ensure the discharge member does not move upwardly away from the lake bottom 20 when water jets exit from the nozzles 18 upon actuation of a water pump (described hereinbelow). Any heavy materials can be used for the weight member 34, such as lead or plastic coated cast iron. The weight member 34 is preferred to be connected externally to the discharge member 14 by straps 34a and 34a&#39;, as shown in FIGS. 1 through 3. The weight member may also be preferably connected internally to the discharge member 14, as shown in FIG. 4, wherein the weight member 34&#39; is preferred to be attached to the discharge member at each closed end cap 15 thereof via a seat 15&#39;. It is preferred that the weight member 34 be replaceable so that more or less weight can be used in relation to the force generated by the jets, as per a selected water pump, to thereby ensure that the discharge member remains adjacent the soil during operation without an undue amount of forceful manipulation by the user. The weight may also be adjusted to suit a user&#39;s preference for deeper penetration of the discharge member into the soil during operation, which can be afforded by heavier weight. It is preferred for the weight member 34 to be co-extensive with the discharge member 14, as shown in FIGS. 1 and 2, although this is not a requirement. 
     The nozzles 18 are preferred to be constructed of metal, such as brass. The nozzles are preferred to partly protrude from the discharge member, as shown in FIGS. 2 and 3. Alternatively, non-protruding nozzles 18&#39; may be preferably used, the nozzles being seated within the discharge member, as shown in FIG. 4. Partly protruding nozzles afford an advantage of deeper water jet penetration into the soil, and a further advantage of some plant and soil agitation, as the nozzles act as tines. Of course, the nozzles must be structurally strong in order to accommodate the forces associated with physical interactions, if protruding nozzles are utilized. 
     A water pump 24 is fluidically connected by a flexible discharge hose 26. The discharge hose 26 is in turn threadably connected to the distal end 22 of the handle 12. An intake hose 28 fluidically connects the intake of the water pump 24 to the body of water 30. It is preferred for the intake hose 28 to include a filtration member 32 at its intake end. 
     The following specifications of an aquatic plant uprooter are presented only by way of example, since other specifications are acceptable. The handle 12 and discharge member 14 are constructed of PVC conduit having a 1.5 inch diameter. The handle has a length of about 5 feet, while the discharge member has a length of about 3 feet. Nozzles 18 each have a diameter of 3/16 inch, are spaced along the entire length of the discharge member at 1.5 inches apart on center, and are of the protruding type, extending outwardly from the discharge member about one-half inch. The water pump 24 has a 2.5 H.P. motor and the pump is of the centrifugal type, rated at 5,700 gallons-per-minute at 20 p.s.i. (an example of such a water pump is that typically used by riparian homeowners for watering their lawns). 
     With reference now being directed to the combination of FIGS. 1 and 6, operation of the aquatic plant uprooter will now be detailed. 
     The user grabs the hand grip 12b and places the discharge member adjacent the lake bottom 20 with the nozzles 18 pointing directly down thereinto. The water pump 24 is thereupon actuated, causing pressurized water W to flow through the handle and discharge member and then emerge as a water jet J from each of the nozzles 18. The water jets churn the soil 20a of the lake bottom 20, undermining the roots by forming a pocket 36 of very loose soil and water, thereby causing the roots 38a of aquatic plants 38 to be freed from the soil 20a (or freed with very little mechanical assist) and then be collected. As can be discerned by reference to FIG. 1, a relatively plant free region 20&#39; in the lake bottom 20 is produced after the discharge member 14 has been passed over that portion of the lake bottom. In this regard, discharge members of narrow cross-section, on the order of 1.5 to 2 inches, may be used by being pulled from a first position away from the user toward the user (direction D in FIG. 6). In this scenario of operation, the user may move the discharge member relative to the lakebottom by walking or by serial steps of walking then stopping and then pulling by the handle. Narrow cross-sectioned discharge members have a tendency to dig into the soil if pushed away from the user. A wide cross-sectioned discharge member, on the order of 4 or more inches, may be used by either pulling toward the user or pushed away from the user across the lakebottom 20. In any event, it is important not to move the discharge member too quickly lest the soil not be sufficiently disturbed as to free the pesky plants, but not so slow that the nozzles dig into the soil so as to bury the discharge member thereinto. 
     The weight of the weight member, nozzle diameter, nozzle spacing, diameter of the discharge member, and water pump head pressure and flow rate are all coordinated so that the discharge member 14 can pass directly over an area of the lakebottom, as depicted in FIG. 6, and thereupon disturb the soil so as to free the plant roots from the soil. It is preferred to use only so much pressure as is necessary to loosen the plant roots from the soil so that they are easily uprooted. In this regard, pressures of between 20 to 60 p.s.i. are preferred, and pressures around 20 p.s.i. are most preferred. Higher pressures tend to result in soil blasting which risks unnecessary environmental damage to the lakebottom soil, while pressures too low will not be sufficient for the water jets to churn the soil so as to undermine the roots of the aquatic plants; the preferred operation pressure is within these two extremes. 
     While the description of operation hereinabove pertains to an individual standing in the water or the adjacent shore, it is also possible to operate the aquatic plant uprooter 10 from a boat or other platform over the water, such as a dock. It is further possible to mount the water pump 24 to a floating platform or position it in a boat or upon some other platform over the water. Further in this regard, it is possible for the aquatic plant uprooter to be constructed on a much larger scale for aquatic plant uprooting of extensive sections of a lakebottom using appropriate support machinery such as a boat mounted derrick. It is still further possible for the handle 12 to be composed of mutually telescoping components or threadably interconnected segments, so that operation from a boat, a dock or the shore is facilitated. 
     Once the aquatic plants have been freed from the soil of the lakebottom by operation of the aquatic plant uprooter 10, the next problem to be solved is collecting the plants. One solution is to let water currents carry them away, but this is unsound and unrealistic. To ensure that neighbors are happy and that floating uprooted plants cannot later re-root, they must be collected and carried to a disposal site. 
     A single step approach to aquatic plant removal is depicted in FIGS. 7 and 8, which show an aquatic plant uprooter 10&#39; equipped with a collection net 40. A frame is composed of a semi-circular brace 42 and a channel member 45 which runs along the top of the discharge member 14 (the internal form of weight member 34&#39; being employed). The semi-circular brace 42 includes elbows 47 which are connected with the channel member 45 by means of common fasteners 43. The apex of the semi-circular brace is connected to the handle by a strap 44 and the channel member is connected to the discharge member also by straps 44. The net 40 is sewn to the semi-circular brace and the channel member and is slung over the discharge member opposite the nozzles 18, so as to have an opening portion 40a for collecting plants located between the semi-circular brace 42 and the discharge member, and an accumulation portion 40b for holding collected plants located forwardly of the discharge member (in a direction away from the handle). In operation, as plants are uprooted, the net collects them and accumulates them for later disposal. This aquatic plant uprooter 10&#39; is preferred for use when there are relatively few plants to be uprooted, such as maintenance of a previously uprooted lakebottom area. 
     Alternatively, the user may want to employ a two step approach to ridding his/her riparian property of aquatic plants, particularly when there is a high density of plants in the area. In this case, the aquatic plant uprooter 10 of FIG. 1 is utilized, followed by a separate collecting operation using a rake-net device 48, as depicted in FIG. 9. In this structure, a handle 12&#39; connects with a perpendicularly oriented cross-member 49 which supports a plurality of rake tines 50. As in the net structure depicted in FIGS. 7 and 8, a semi-circular brace 42&#39; connects with a channel member 45&#39;, and the semi-circular brace and channel member connect to the handle and the cross-member by means of straps 44&#39;. A net 40&#39; has a collection portion 40a&#39; and an accumulation portion 40b&#39; and is attached in the manner described above with respect to FIGS. 7 and 8. In operation the tines stir-up the soil and rake the aquatic plants, while the net collects and stores them for later disposal. 
     To those skilled in the art to which this invention appertains, the above described preferred embodiment may be subject to change or modification. Such change or modification can be carried out without departing from the scope of the invention, which is intended to be limited only by the scope of the appended claims.