AU2020201088A1 - Mobile Plant Termination System - Google Patents

Abstract

A mobile plant termination system comprising a nozzle assembly that comprises a support frame adapted to couple to a vehicle, a floating mount to which a plant guide is movably mounted, the floating mount connected to the support frame for floating movement relative to the vehicle; a nozzle mounted to the plant guide and adapted to discharge a jet of fluid; a ground support mounted to the floating mount to permit movement of the plant guide across the ground maintaining the nozzle at a predetermined height above the ground, the plant guide adapted to contact a plant for lateral movement of said plant guide relative to the floating mount and the associated ground support thus compensating for variations in separation between the ground support and the plant to increase the likelihood of the jet of fluid discharged from the nozzle being predominantly directed at the plant. 1/9 c-NU -- -- --- CDJ tL

Description

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MOBILE PLANT TERMINATION SYSTEM

Technical Field

[0001] The present invention relates broadly to a mobile nozzle assembly as well as a nozzle head assembly, typically for application in the termination or killing of plants. The invention is also broadly directed to a mobile plant termination system.

Background of Invention

[0002] In crop farming, the rotation or removal of crops is often difficult with some of the more persistent plants. The cotton plant when slashed is particularly susceptible to regrowth requiring labour intensive removal or killing. Furthermore, cotton in its genetically modified form, although more pest resistant, is increasing difficult to terminate for soil remediation in the course of crop rotation. The applicant is aware of relatively recent technology directed to soil cultivation using a high pressure fluid jet system. The jet system includes a fluid jet cutting head which is directed at the ground for cutting stubble residues and the underlying soil. The cutting head is mounted to a traveller arrangement which rides across the ground. This technology is the subject of Australian patent application no. 2017202558 and corresponding foreign patent applications. Although the system provides an interesting alternative to more conventional soil cultivation, it is not suitable for above ground crop removal for at least the following reasons: i) the jet system operates at the stubble level or within the soil; ii) the cutting head rides with the traveller arrangement and thus follows effectively the same path as the traveller; iii) the jet system is designed specifically for soil cultivation largely independent of the crop or plant.

[0003] Another known approach in removing or killing crops is foliar application where diluted chemicals are applied to the plant leaves or foliage. This approach typically involves multiple stages where the foliage is first sprayed with a diluted chemical and any regrowth subsequently sprayed again in a "double knock technique". This technique is both time consuming and expensive, particularly with genetically modified crops which are chemical resistant and thus difficult to kill.

Summary of Invention

[0004] According to a first aspect of the present invention there is provided a mobile nozzle assembly comprising: a support frame adapted to couple to a vehicle; a floating mount to which a plant guide is movably mounted, the floating mount connected to the support frame for floating movement relative to the vehicle; a nozzle mounted to the plant guide and adapted to discharge a jet of fluid; a ground support mounted to the floating mount to permit movement of the plant guide across the ground maintaining the nozzle at a predetermined height above the ground, the plant guide adapted to contact a plant for lateral movement of said plant guide relative to the floating mount and the associated ground support thus compensating for variations in separation between the ground support and the plant to increase the likelihood of the jet of fluid discharged from the nozzle being predominantly directed at the plant.

[0005] According to a second aspect of the invention there is provided a nozzle head assembly comprising: a floating mount; a plant guide movably mounted to the floating mount; a nozzle mounted to the plant guide and adapted to discharge a jet of fluid; a ground support mounted to the floating mount to permit movement of the plant guide across the ground maintaining the nozzle at a predetermined height above the ground, the plant guide adapted to contact a plant for lateral movement of said plant guide relative to the floating mount and the associated ground support thus compensating for variations in separation between the ground support and the plant to increase the likelihood of the jet of fluid discharged from the nozzle being predominantly directed at the plant.

[0006] According to a third aspect of the invention there is provided a mobile plant termination system comprising: a fluid reservoir adapted to contain fluid to be applied to plants; a pump operatively coupled to the fluid reservoir to pressurise fluid from said reservoir to provide a pressurised fluid; a floating mount to which a plant guide is movably mounted; one or more nozzles associated with the pump to receive the pressurised fluid, at least one of the nozzles being mounted to the plant guide and adapted to discharge a jet of fluid; a ground support mounted to the floating mount to permit movement of the plant guide across the ground maintaining said at least one nozzle at a predetermined height above the ground, the plant guide adapted to contact at least one of the plants for lateral movement of said plant guide relative to the floating mount and the associated ground support thus compensating for variations in separation between the ground support and said at least one plant to increase the likelihood of the jet of fluid discharged from the nozzle being predominantly directed at said at least one plant.

[0007] Preferably the plant guide includes a guide arm movably coupled to the floating mount, the guide arm configured to contact the plant for the lateral movement required to compensate for variations in separation between the ground support and the plant. More preferably the guide arm is pivotally coupled to the floating mount for pivotal movement of the guide arm toward said floating mount on contact of the guide arm with the plant. Even more preferably the plant guide includes biasing means arranged to pivotally bias the guide arm outward from the floating mount. Alternatively, the plant guide includes an opposing pair of convergent arms together defining a tapered channel within which the plant is received to effect the required lateral movement of said plant guide.

[0008] Preferably the guide arm is one of a pair of guide arms extending outwardly on opposing sides of the ground support mounted to the floating mount. More preferably each of the pair of guide arms is independent of each other and pivotally coupled to the floating mount, said pair of guide arms adapted to contact respective of a pair of opposing plants from opposing rows of plants. Even more preferably each of the pair of guide arms is biased outward of the floating mount via respective of a pair of biasing means. Alternatively, the pair of guide arms are interconnected for pivotal movement about the floating mount in concert with one another.

[0009] Preferably the nozzle is rigidly mounted to the guide arm of the plant guide. Alternatively, the nozzle is rigidly mounted to one of the pair of convergent members of said plant guide. More preferably the nozzle is mounted at a fixed and predetermined angle wherein the jet of fluid discharged from the nozzle is directed at an angle of between 0 to 200 relative to the ground.

[0010] Preferably the ground support includes a wheel rotationally mounted to a wheel support which is movably mounted to the floating mount for movement of the wheel relative to the floating mount to vary the predetermined height at which the nozzle is maintained above the ground. More preferably the wheel support is pivotally mounted to the floating mount and designed to cooperate with a locking element for locking of the wheel support at one of a plurality of pivotal positions depending on the required predetermined height.

[0011] Preferably the support frame includes a pair of parallel legs pivotally connected at their distal ends to the floating mount to permit vertical movement of said floating mount whilst maintaining its angular disposition relative to the ground. More preferably the support frame includes a support arm to which the pair of parallel legs at their proximal ends are pivotally connected. Even more preferably the support frame includes a flexible linkage of a predetermined length connected between one of the parallel legs and the floating mount to limit vertical separation of the support arm and the floating mount.

[0012] Preferably the mobile nozzle assembly also comprises a coupling sub assembly connected to the support frame and designed for detachable coupling of said frame to the vehicle. More preferably the coupling sub-assembly includes a clamp arrangement for releasably clamping to a carrier frame or tool bar associated with a hitch or other tow element of the vehicle. Even more preferably the support frame is movably connected to the coupling sub-assembly whereby collision of the mobile nozzle assembly with an obstruction causes the support frame and the associated floating mount and ground support to move clear of the obstruction. Still more preferably the coupling sub-assembly includes biasing means operatively coupled to the support frame to urge it and the associated equipment into an operative position, the biasing means designed to permit movement away from the operative position on application of a threshold force to the floating mount on collision with an obstruction. Alternatively, the coupling sub-assembly includes a breakaway mechanism connected to the support frame, said breakaway mechanism being designed to fail on application of a threshold force to the floating mount thereby permitting pivotal movement away from the operative position.

[0013] According to a fourth aspect of the invention there is provided a nozzle assembly comprising: a nozzle adapted to discharge a jet of fluid; a plant guide to which the nozzle is mounted, the plant guide adapted to contact a plant for lateral movement of said plant guide thus compensating for variations in placement of the plant to increase the likelihood of the jet of fluid discharged from the nozzle being predominantly directed at the plant.

Brief Description of Drawings

[0014] In order to achieve a better understanding of the nature of the present invention a preferred embodiment of a mobile nozzle assembly as well as a nozzle head assembly will now be described, by way of example only, with reference to the accompanying drawings in which:

Figure 1 is a front perspective view from above of one embodiment of a mobile nozzle assembly according to the present invention;

Figure 2 is a front perspective view from below of the mobile nozzle assembly of the embodiment of figure 1;

Figure 3 is a side view of the mobile nozzle assembly of the embodiment of the preceding figures;

Figure 4 is a front perspective view from above of another embodiment of a mobile nozzle assembly according to the invention;

Figure 5 is front perspective view from below of the mobile nozzle assembly of the other embodiment of figure 4;

Figure 6 is a rear perspective view from above of the mobile nozzle assembly of the other embodiment of figures 4 and 5;

Figure 7 is a front perspective view from above of a further embodiment of a mobile nozzle assembly according to the invention;

Figure 8 is a top view of the mobile nozzle assembly of the further embodiment of figure 7;

Figure 9 is a side view of the mobile nozzle assembly of the further embodiment of figures 7 and 8.

Detailed Description

[0015] As seen in figures 1 to 3, there is a mobile nozzle assembly 10 in this first embodiment adapted to couple to a tow vehicle such as a tractor (not shown). The tractor is driven typically with the assistance of a GPS navigation system through a crop of plants for termination of the plants (not shown). The mobile nozzle assembly of this embodiment generally comprises:

1. a support frame 12 adapted to couple to a carrier frame or tool bar 14 associated with a hitch or other tow element of a tow vehicle (not shown); 2. a floating mount 18 connected to the support frame 12 for floating movement relative to the tow vehicle; 3. a plant guide 20 moveably mounted to the floating mount 18; 4. a nozzle 22 mounted to the plant guide 20 and adapted to discharge a jet of fluid (not shown); 5. a ground support in the form of a wheel 24 mounted to the floating mount 18 to permit movement of the plant guide 20 across the ground maintaining the nozzle 22 at a predetermined height above the ground.

[0016] Importantly, the plant guide 20 is adapted to contact a plant (not shown) for lateral movement relative to the floating mount 18. This lateral movement compensates or adjusts for variations in separation between the wheel 24 and the plant to increase the likelihood of the jet of fluid discharged from an orifice 25 of the nozzle 22 being predominantly directed at the plant.

[0017] In this embodiment the plant guide 20 includes a guide arm 26 pivotally coupled to the floating mount 18 and configured to contact the plant to effect the required lateral movement of the guide arm 26. The guide arm 26 at its free end includes a skid member 27 to which the nozzle 22 is rigidly mounted. In this example the plant guide 20 includes biasing means in the form of a tension spring such as 28a arranged to pivotally bias the guide arm 26a outward from the floating mount 18 allowing the guide arm 26 to follow the plant line variations. The springs 28a or 28b are tensioned to allow the respective guide arms 26a or 26b to swing inwards if they hit or otherwise collide with an immovable object. The guide arm 26a is one of a pair of guide arms 26a and 26b extending outwardly on opposing sides of the wheel 24 mounted centrally of the floating mount 18. Each of the pair of guide arms 26a/b is pivotally coupled to the floating mount 18 independent of each other and designed to contact respective of a pair of opposing plants from opposing rows of plants (not shown).

[0018] The nozzle is one of a pair of the nozzles 22a and 22b each being mounted at a fixed and predetermined angle relative to the respective guide arm 26a and 26b. This means in this embodiment the jet of fluid discharged from the nozzle orifice 25 is directed at an angle of between 0 to 20 degrees relative to the ground. In this case the jet of fluid is intended primarily for terminating the plant. The plant is generally terminated by cutting partway through its stem via the jet of fluid. The jet of fluid may be pressurised at the nozzle at up to around 50,000psi. The fluid discharged from the nozzle includes but is not limited to water, insecticide, herbicide, fertiliser or other chemicals, or a mixture of any one or more of these liquids. The fluid used will depend largely on the required purpose to which the mobile nozzle assembly is applied. For example, water alone may be used if the sole purpose is complete cutting or slashing of the plant stem whereas water with a predetermined concentration of chemical may be adopted for killing the plant by injecting the stem with the diluted chemical.

[0019] As best seen in figure 2, in this embodiment the wheel 24 is rotationally mounted to a wheel support 30 mounted to the floating mount 18. The position of the wheel 24 relative to the floating mount 18 determines the predetermined height at which the nozzle such as 22a is maintained above the ground. The predetermined height of the nozzle 22a may depend on one or more of the following factors:

1. the purpose to which the mobile nozzle assembly is being applied i.e. primarily for slashing of the plant, or alternatively for part cutting of the stem and injecting it with a diluted chemical; 2. whether or not the plant has already been slashed above the ground; 3. the type and nature of the plant or crop being terminated or killed; 4. the consistency of the ground or terrain across which the mobile nozzle assembly is moved.

[0020] It is expected that the mobile nozzle assembly 10 will be particularly well suited to the termination of cotton plants. In this example it is likely that the predetermined height at which the nozzle such as 22a is maintained will affect cutting of the cotton plant at around 50mm to 100mm above ground. It will be understood that for the purpose of terminating other plants or crops this predetermined height may vary.

[0021] The support frame 12 of this embodiment includes a pair of parallel legs 32a and 32b pivotally connected at their distal ends to a bracket 33 connected to the floating mount 18. The support frame 12 is thus of a parallelogram structure designed to permit raising or lowering of the floating mount 18 relative to the tool bar 14 depending on the topography of the ground whilst maintaining the angular disposition of the floating mount 18. The support frame 12 of this example includes a support arm 34 to which the pair of parallel legs 32a/b are at their proximal ends pivotally connected. The support arm 34 has its pivotal connections to the pair of legs 32a/b in a plane generally parallel to pivotal connection of the legs 32a/b to the. The support arm 34 is clamped or otherwise connected to the tool bar 14. As best seen in figure 3, the support frame 12 may optionally include a rod 36 and associated compression spring 38 to urge the floating mount 18 and the associated wheel 24 down to maintain ground engagement. In this case, the rod 36 extends between the bracket 33 associated with the floating mount 18, and the lower of the legs 32b.

[0022] As best seen in figure 1, the nozzle assembly 10 may include biasing means in the form of spring 40 designed to allow its respective guide arm 26 to lift if it comes in contact with an object. Each of the springs such as 40a is connected between a pivotal mounting bracket 42a associated with the guide arm 26a, and a fixed bracket 44a connected to the floating mount 18. The pivotal mounting bracket 42a is arranged to pivot about the fixed bracket 44 to allow lifting of the associated guide arm 26a on contact with an object.

[0023] As seen in figures 4 to 6, there is another embodiment of a mobile nozzle assembly 100 according to the invention and in this case to be applied for the termination of plants. For ease of reference and in order to avoid repetition, like components of this embodiment compared with the preceding embodiment have been designated with an additional "0". For example, the support frame is designated at 120 and the wheel at 240. The wheel 240 is shown exploded from the remainder of the mobile nozzle assembly 100.

[0024] In this other embodiment the plant guide 200 is limited to one side of the floating mount 180 and the associated wheel 240. The plant guide 200 includes an opposing pair of convergent arms 21Ca and 21Ob together defining a tapered channel 230 within which the plant is received. The innermost of the pair of convergent arms 21a extends into the floating mount 180 where it is pivotally connected. The pair of convergent arms 21a/b are held together via a bridge structure 240 which also houses the nozzle 220. The plant guide 200 thus contacts the plant which effects lateral movement of the plant guide 200 compensating for variations and separation between the wheel 240 and the plant which is channelled into the tapered channel 230 where it is exposed to the jet of fluid from the nozzle 220.

[0025] As best seen in figure 5, the wheel support 300 associated with the wheel 240 of this embodiment is pivotally mounted to the floating mount 180 of the nozzle mount assembly 160. The wheel support 300 cooperates with a locking element or screw (not shown) which is received within a slot 270 formed in the wheel support 300. The wheel support 300 can thus be pivoted into one of a plurality of pivotal positions depending on the required predetermined height at which the nozzle 220 is to be maintained above the ground, and the locking screw locked to effect locking of the wheel support 300 at the selected pivotal position. The predetermined height of the nozzle 220 can therefore be set depending on the factors described in the context of the earlier embodiments.

[0026] The mobile nozzle assembly 100 of this embodiment also comprises a coupling sub-assembly 290 connected to the support frame 120 and designed for detachable coupling of the support frame 120 to the tool bar40. The coupling sub assembly 290 includes a clamp arrangement 310 for releasably clamping to the tool bar 140 associated with a hitch of the tow vehicle. The support arm 340 is movably mounted within a head arrangement 330 of the coupling sub-assembly 290. The head arrangement 330 includes biasing means in the form of pneumatic damper 350 arranged to urge the support frame 120 and the associated floating mount 180 into an operative position for presentment of the nozzle 220 to the plant on guided entry via the plant guide 200. In the event the floating mount 180 collides with an obstruction, the damper 350 is designed to permit movement of the support frame 120 and the associated equipment away from the operative position. That is, the damper 350 permits lateral displacement of the support arm 340 on application of a threshold forced to the floating mount 180 on collision with an obstruction. The floating mount 180 and the associated wheel 240 are thus move clear of the obstruction which may otherwise damage the mobile nozzle assembly 100.

[0027] Although not illustrated, the support frame 120 may include a flexible linkage connected between the lower of the parallel legs 320b and the floating mount 180. The flexible linkage is of a fixed predetermined length and configured to limit vertical separation of the floating mount 180 and the support arm 340 or the tool bar 140 to which it is clamped. The flexible linkage may be effective in operation in limiting the range of movement of the floating mount 180, or to lift the floating mount 180 when it is not in use during transportation.

[0028] As seen in figures 7 to 9, there is a further embodiment of a mobile nozzle assembly 1000 according to the invention and in this case to be applied for the termination of plants. For ease of reference and in order to avoid repetition, like components of this further embodiment compared with the first embodiment have been designated with an additional "00". For example, the support frame is designated at 1200 and the floating mount at 1800.

[0029] This further embodiment of the mobile nozzle assembly 1000 is substantially the same as the first embodiment with the following exceptions:

1. the wheel 24 of the first embodiment is replaced with a pair of wheels 2400a and 2400b; 2. the wheel support 3000 of this further embodiment includes coupling arrangement 6100 pivotally mounted to the floating mount 1800.

[0030] The pair of wheels 2400a and 2400b having respective of link members 5100a and 5100b pivotally connected to and located either side of a mounting bracket 5300 of the wheel support 3000. The pair of wheels 2400a and 2400b are thus located one behind the other and designed to hinge relative to one another to provide smooth travel for the floating mount 1800 and its associated equipment.

[0031] The coupling arrangement 6100 of this further embodiment includes a lower link member 6300 pivotally connected at respective of its opposing ends to the mount bracket 5300 and the floating mount 1800. The coupling arrangement 6100 also includes a threaded mechanical actuator in the form of a turnbuckle 6500 connected at respective of its opposing ends to the mount bracket 5300 and the floating mount 1800.

[0032] In another aspect, the invention is broadly directed to a mobile plant termination system (not illustrated). The system may include a plurality of the nozzle assemblies such as 10 and 100 of the preceding embodiments connected to a common tool bar associated with a hitch or other tow element of a tow vehicle. The plurality of nozzle head assemblies may, depending on their design, be dedicated to a single or opposing pair of rows of plants providing broad crop coverage. Although not illustrated, the mobile system may also comprise:

1. a fluid reservoir adapted to contain fluid to be applied to plants; 2. a pump operatively coupled to the fluid reservoir to pressurise fluid in providing a pressurised fluid.

[0033] The fluid reservoir and the pump may be typically located at the tow vehicle for the provision of the pressurised fluid to each of the mobile nozzle assemblies such as 10 or 100. In this case, each of the nozzles such as 22 or 220 receives the pressurised fluid from the pump via a pressurised fluid line.

[0034] In its broadest aspect, the invention is directed to a nozzle assembly comprising a nozzle adapted to discharge a jet of fluid, and a plant guide to which the nozzle is mounted. The plant guide may take the form of a resiliently flexible plant guide member designed to contact a plant and flex resiliently wherein the plant guide is moved laterally to compensate for variations in placement of the plant. The nozzle is mounted to the flexible plant guide member so that the likelihood of the jet of fluid discharged from the nozzle being predominantly directed at the plant is increased. In this broadest aspect the invention does not include a wheel or other ground engaging device. The resiliently flexible plant guide member may at its distal end contact and follow the ground contour ensuring the nozzle is maintained at a predetermined height above the ground.

[0035] Now that several preferred embodiments of the mobile nozzle assembly have been described it will be apparent to those skilled in the art that they have at least the following advantages:

1. the nozzle being mounted to the plant guide is presented in close proximity to the plant without requiring either accurate manoeuvring of the tow vehicle or consistent placement of the plants in a row; 2. the mobile nozzle assembly including the ground support effectively controls the height of the floating mount for presenting the nozzle and its jet of fluid at the predetermined height above the ground for contact with the plant; 3. the support frame of the preferred embodiment is of a parallelogram structure which means that the floating mount remains in generally the same angular disposition to the ground regardless of its vertical movement and position as it travels across uneven ground; 4. the mobile nozzle assembly and nozzle head assembly are suitable for, or capable of integration with, existing agricultural equipment.

[0036] Those skilled in the art will appreciate that the invention as described herein is susceptible to variations and modifications other than those specifically described. For example, the plant guide may include multiple nozzles rather than the single nozzle arrangement of the preferred embodiments. The pair of guide arms of the preferred embodiment may be interconnected for pivotal movement in concert about the floating mount in which case they are likely to float in a pivoting action without being biased. Alternatively the mobile nozzle assembly of the preferred embodiment may be limited to a single guide arm and associated nozzle. All such variations and modifications are to be considered within the scope of the present invention the nature of which is to be determined from the foregoing description.

Claims (25)

Claims

1. A mobile nozzle assembly comprising: a support frame adapted to couple to a vehicle; a floating mount to which a plant guide is movably mounted, the floating mount connected to the support frame for floating movement relative to the vehicle; a nozzle mounted to the plant guide and adapted to discharge a jet of fluid; a ground support mounted to the floating mount to permit movement of the plant guide across the ground maintaining the nozzle at a predetermined height above the ground, the plant guide adapted to contact a plant for lateral movement of said plant guide relative to the floating mount and the associated ground support thus compensating for variations in separation between the ground support and the plant to increase the likelihood of the jet of fluid discharged from the nozzle being predominantly directed at the plant.

2. A nozzle head assembly comprising: a floating mount; a plant guide movably mounted to the floating mount; a nozzle mounted to the plant guide and adapted to discharge a jet of fluid; a ground support mounted to the floating mount to permit movement of the plant guide across the ground maintaining the nozzle at a predetermined height above the ground, the plant guide adapted to contact a plant for lateral movement of said plant guide relative to the floating mount and the associated ground support thus compensating for variations in separation between the ground support and the plant to increase the likelihood of the jet of fluid discharged from the nozzle being predominantly directed at the plant.

3. A mobile plant termination system comprising: a fluid reservoir adapted to contain fluid to be applied to plants; a pump operatively coupled to the fluid reservoir to pressurise fluid from said reservoir to provide a pressurised fluid; a floating mount to which a plant guide is movably mounted; one or more nozzles associated with the pump to receive the pressurised fluid, at least one of the nozzles being mounted to the plant guide and adapted to discharge a jet of fluid; a ground support mounted to the floating mount to permit movement of the plant guide across the ground maintaining said at least one nozzle at a predetermined height above the ground, the plant guide adapted to contact at least one of the plants for lateral movement of said plant guide relative to the floating mount and the associated ground support thus compensating for variations in separation between the ground support and said at least one plant to increase the likelihood of the jet of fluid discharged from the nozzle being predominantly directed at said at least one plant.

4. An assembly or system as claimed in any one of the preceding claims wherein the plant guide includes a guide arm movably coupled to the floating mount, the guide arm configured to contact the plant for the lateral movement required to compensate for variations in separation between the ground support and the plant.

5. An assembly or system as claimed in claim 4 wherein the guide arm is pivotally coupled to the floating mount for pivotal movement of the guide arm toward said floating mount on contact of the guide arm with the plant.

6. An assembly or system as claimed in either claims 4 or 5 wherein the plant guide includes biasing means arranged to pivotally bias the guide arm outward from the floating mount.

7. An assembly or system as claimed in any one of claims 1 to 3 wherein the plant guide includes an opposing pair of convergent arms together defining a tapered channel within which the plant is received to effect the required lateral movement of said plant guide.

8. An assembly or system as claimed in any one of claims 4 to 6 wherein the guide arm is one of a pair of guide arms extending outwardly on opposing sides of the ground support mounted to the floating mount.

9. An assembly or system as claimed in claim 8 wherein each of the pair of guide arms is independent of each other and pivotally coupled to the floating mount, said pair of guide arms adapted to contact respective of a pair of opposing plants from opposing rows of plants.

10. An assembly or system as claimed in either of claims 8 or 9 wherein each of the pair of guide arms is biased outward of the floating mount via respective of a pair of biasing means.

11. An assembly or system as claimed in claim 8 wherein the pair of guide arms are interconnected for pivotal movement about the floating mount in concert with one another

12. An assembly or system as claimed in any one of claims 4 to 6 wherein the nozzle is rigidly mounted to the guide arm of the plant guide.

13. An assembly or system as claimed in claim 8 wherein the nozzle is rigidly mounted to one of the pair of convergent members of said plant guide.

14. An assembly or system as claimed in any one of the preceding claims wherein the nozzle is mounted at a fixed and predetermined angle wherein the jet of fluid discharged from the nozzle is directed at an angle of between 0 to 200 relative to the ground.

15. An assembly or system as claimed in any one of the preceding claims wherein the ground support includes a wheel rotationally mounted to a wheel support which is movably mounted to the floating mount for movement of the wheel relative to the floating mount to vary the predetermined height at which the nozzle is maintained above the ground.

16. An assembly or system as claimed in claim 15 wherein the wheel support is pivotally mounted to the floating mount and designed to cooperate with a locking element for locking of the wheel support at one of a plurality of pivotal positions depending on the required predetermined height.

17. An assembly as claimed in any one of the preceding claims (when it depends on claim 1) wherein the support frame includes a pair of parallel legs pivotally connected at their distal ends to the floating mount to permit vertical movement of said floating mount whilst maintaining its angular disposition relative to the ground.

18. An assembly as claimed in claim 17 wherein the support frame includes a support arm to which the pair of parallel legs at their proximal ends are pivotally connected.

19. An assembly as claimed in claim 18 wherein the support frame includes a flexible linkage of a predetermined length connected between one of the parallel legs and the floating mount to limit vertical separation of the support arm and the floating mount.

20. An assembly as claimed in any one of claims 17 to 19 also comprising a coupling sub-assembly connected to the support frame and designed for detachable coupling of said frame to the vehicle.

21. An assembly as claimed in claim 20 wherein the coupling sub-assembly includes a clamp arrangement for releasably clamping to a carrier frame or tool bar associated with a hitch or other tow element of the vehicle.

22. An assembly as claimed in either of claims 20 or 21 wherein the support frame is movably connected to the coupling sub-assembly whereby collision of the mobile nozzle assembly with an obstruction causes the support frame and the associated floating mount and ground support to move clear of the obstruction.

23. An assembly as claimed in any one of claims 20 to 22 wherein the coupling sub-assembly includes biasing means operatively coupled to the support frame to urge it and the associated equipment into an operative position, the biasing means designed to permit movement away from the operative position on application of a threshold force to the floating mount on collision with an obstruction.

24. An assembly as claimed in claim 20 wherein the coupling sub-assembly includes a breakaway mechanism connected to the support frame, said breakaway mechanism being designed to fail on application of a threshold force to the floating mount thereby permitting pivotal movement away from the operative position.

25. A nozzle assembly comprising: a nozzle adapted to discharge a jet of fluid; a plant guide to which the nozzle is mounted, the plant guide adapted to contact a plant for lateral movement of said plant guide thus compensating for variations in placement of the plant to increase the likelihood of the jet of fluid discharged from the nozzle being predominantly directed at the plant.