WO2001019166A1 - Portable microclimate isolation and control system - Google Patents

Abstract

A method of eradicating undesirable plant species including poa annua, comprising: isolating a region of vegetative cover such as a region of turf grass comprising bentgrass and poa annua from an ambient environment; and varying at least one of the temperature and humidity of the isolated microclimate region to a temperature which detrimentally affects the undesired plant species (e.g.: poa annua), yet does not detrimentally affect the desired plant species (e.g.: bentgrass).

Description

PORTABLE MICROCLIMATE ISOLATION AND CONTROL SYSTEM

CROSS-REFERENCES TO RELATED APPLICATIONS

This application claims the benefit of Provisional Patent Application Serial No. 60/154,451 filed September 17, 1999 (Attorney docket 19803-000200US), in the name of the present assignee, and hereby incorporated by reference for all purposes.

TECFfNICAL FIELD

The present invention relates generally to systems for treating vegetative cover to suppress the growth and proliferation of undesirable grasses, and in one preferred aspect to systems for eradicating bluegrass (Poa Annua) on golf course greens.

BACKGROUND OF THE INVENTION It is typically desirable to maintain areas of vegetative cover such that they have a minimum of unwanted plant species and insect pests. This is true for lawns in general, and is especially true in the case of a golf course green. Specifically, it is very desirable to reduce various weed-grasses, including, but not limited to, "poa annua" on golf course greens.

Poa annua, otherwise known as perennial-annual bluegrass is a ubiquitous "weed grass", which grows on golf course greens together with more desirable bentgrasses. Unfortunately, the growth of poa annua on golf course greens is almost unavoidable. Poa annua is particularly annoying to golfers due to its frequent seed production. In contrast, the growth of more desirable bentgrasses on the green offer the advantageous properties of a uniform putting surface. As a result, it is typically desirable to eradicate the bluegrass from a golfing green containing a population of bentgrass. Unfortunately, systems for eradicating poa annua typically have adverse impacts upon the desirable bentgrasses as well.

SUMMARY OF THE INVENTION The present invention provides a portable microclimate isolation and control system which is adapted to suppress or eradicate undesirable plant species in an area of vegetative cover. In a preferred aspect, the present invention provides methods and apparatus which may be used for suppressing or eradicating poa annua from golf course greens, or similar surfaces such as golf tees, lawn bowling greens, or grass tennis courts which typically comprising both undesirable poa annua and desirable bentgrasses. An advantage of the present invention is that it provides such methods and apparatus without damaging or adversely effecting the desirable bentgrasses.

In a preferred aspect of the invention, systems are provided for isolating a region of turf grass on a golf course green which comprises both undesirable poa annua and desirable bentgrasses. In one preferred aspect, the temperature of the isolated region is raised to a level which is detrimental to the growth of poa annua, yet does not cause damage to the bentgrass. In another preferred aspect of the invention, the humidity of the isolated region is also raised to a level which detrimentally affects the poa annua without causing damage to the bentgrass. An advantage of raising the humidity of the isolated region is that it makes the poa annua more sensitive to heat such that it will also become more sensitive to selective grass pathogens such as Xanthamonas Campestris. In other preferred aspects, both the temperature and humidity are simultaneously raised within the isolated region comprised of poa annua and bentgrass, thereby detrimentally affecting the growth of the poa annua or viability of its seed without significantly detrimentally affecting the growth of the surrounding bentgrasses.

The present invention is not limited to reducing or eradicating poa annua in particular. Rather, by providing a portable system which is positioned over and thereby isolates a "microclimate" within a region of vegetative cover such as a lawn or a golf course green, the temperature and/or humidity in the isolated region of the lawn or a golf course green can be controlled, and a large number of various undesirable plant species can be selectively controlled. In addition, various insect infestations and fungal infestations can also be controlled.

Advantages of the present invention include the fact that it does not rely upon the use of herbicides or other chemicals which both adversely effect the desired plant species (e.g.: bentgrasses) and contribute to environmental degradation. Further advantages of the present invention include the fact that increased temperature and humidity in the isolated region of grass will adversely affect harmful turf insects which are also detrimental to the desired bentgrasses.

Yet a further advantage of the present invention is that it can be used to protect the isolated microclimate from inclement weather (e.g.: frost), and/or enhance biologic or chemical treatment of plant growth or soil. In addition, the present invention may be used to inhibit fungal growth and reduce insect parasites such as beetles, worms and mites.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is an illustration of a portable microclimate isolation and control system, comprising a tarp which isolates and insulates a region of turf grasses from ambient weather conditions.

Fig. 2 is an illustration of a portable microclimate isolation and control system containing electrically activated heating elements for isolating and insulating a region of turf grasses from ambient weather conditions.

Fig. 3 is an illustration of a portable microclimate isolation and control system which circulates fluid therethrough for isolating and insulating a region of turf grasses from ambient weather conditions.

Fig. 4 is an illustration of a portable microclimate isolation and control system incorporating heated air movement thereunder for isolating and insulating turf grasses from ambient weather conditions.

Fig. 5 is a cut away view of a sectional domed covering for isolating and controlling a microclimate.

DESCRIPTION OF THE SPECIFIC EMBODIMENTS

The present invention provides a portable microclimate isolation and control system which is adapted to control the growth and proliferation of undesirable plants by isolating a region of vegetative cover from its surrounding (ie: ambient) environment, and controllably altering at least one of the temperature and humidity in the isolated region, thereby producing conditions unfavorable to the growth or proliferation of the undesirable plant species.

In preferred aspects, the present invention controls at least one of the temperature and humidity in a "canopy" region (i.e.: within the leaves of the grass just above the thatch and ground surface) as ambient temperature and humidity even just a few inches above the ground may differ considerably from temperature and humidity in the canopy. In one preferred aspect, the present invention provides a system which is ideally suited for eradicating poa annua growing in a bentgrass golf green. In preferred aspects, a region of turf grasses, comprising both undesirable poa annua and desirable bentgrass, is isolated from normal ambient weather conditions, such as by way of a tarp covering. Thereafter, either or both of the temperature and/or humidity are elevated to prefeπed conditions in a region of turf grass under the tarp. Preferably, the tarp covering will also insulate the isolated region of turf grass, such that the amount of energy required to raise the temperature of the isolated region is conserved. The present "tarp" covering may alternatively comprise a covering placed directly on top of the vegetative cover, or a "dome" or "bubble" which is positioned over the vegetative cover with an interior air filled volume separating the top of the dome from the vegetative cover, and acting as a controlled microclimate.

The particular desirable temperature and humidity ranges applied in the isolated region are selected such that they are damaging to the poa annua, yet are not detrimental to the desirable bentgrasses. When the present invention is used to treat various other undesirable plant species besides poa annua, the temperature and humidity are adjusted accordingly. As such, at least one of the temperature or humidity within the isolated region may be raised or lowered to a range in which growth of the undesirable plant is inhibited, but at which the desired plants or grasses are not affected.

In a preferred aspect of the present invention, when treating poa annua, the isolated region is elevated in temperature to between 115°F and 120°F. Preferably, this increased temperature is maintained for about two hours. Poa annua is typically not tolerant of extreme heat in excess of 115°F, whereas normal bentgrass is not tolerant of extreme heat in the range of 120°F. Accordingly, by raising the temperature of the isolated region to between 115°F and 120°F, it is possible to detrimentally effect the poa annua, yet avoid detrimental effects to the desired surrounding bentgrass.

In preferred aspects of the present invention, the elevated temperature is maintained in the range of 115°F to 120°F for a time period in the range of at least one to three, and most preferably about two hours. This two hour time period is preferred as shorter time periods would require the application of higher temperatures which are detrimental to the desirable bentgrass.

Referring to Fig. 1, a turf grass green 10 comprising desired bentgrasses 12 and undesired poa annua 14 is shown. A covering 20 is preferably laid down over a region of a turf grass green 10, as shown. Covering 20 may preferably comprise a tarp. Covering 20 isolates and preferably insulates a region of a turf grass green 10, (comprising bentgrasses 12 and poa annua 14) from the surrounding ambient weather conditions.

Covering 20 acts to retain heat in a region of a turf grass green 10, such that heat, (and preferably humidity as well), would be increased to the desired ranges of the present method. In particular, covering 20 is applied to the region of turf grass such that the temperature of poa annua 14 and bentgrasses 12 is elevated to the range of about 115°F to 120°F, for approximately several hours, and preferably two (2) hours.

It is to be understood that the present invention is not limited to the specific temperature ranges which are disclosed herein as a preferred example. Rather, various other temperature and humidity ranges are encompassed within the scope of the present invention, provided only that such temperature and humidity ranges are detrimental to the poa annua, without being detrimental to the surrounding bentgrasses.

Fig. 2 illustrates another embodiment of the invention in which covering 22 has heating coils 24 therein for selectively increasing the temperature of the isolated region of turf grass green 10 disposed thereunder.

Fig. 3 illustrates yet another embodiment of the invention in which covering 30 has at least one fluid channel 32 disposed therein. Fluid channels 32 are preferably adapted to conduct heated water therethrough, again for the purpose of heating the isolated region of turf grass green 10 covered by covering 30.

Fig. 4 shows a cut-away view of a covering 40 covering and thereby isolating a region of turf grass green 10 from the surrounding environment. An air blower/heater/humidifier 42 passes heated air through vent 44 such that the region of turf grasses 10 under covering 40 is heated to the desired range. In alternate aspects, a radiant heat source can be substituted for the illustrated blower/heater/humidifier 42, as desired.

Preferably, the above described coverings 20, 22, 30, and 40 are fabricated to be black or other dark color, so as to enhance their ability to heat isolated region 10 of poa annua 14 and bentgrass 12 under natural sunlight.

Coverings 20, 22, 30, and 40 are preferably fabricated from suitable materials, so as to provide insulation such that the heat trapped thereunder does not readily escape to the ambient environment.

In preferred aspects, coverings 20, 23, 30 and 40 may be held in fixed positions on the ground by rocks or sandbags disposed around their perimeter, or alternatively by tent-type stakes passing therethrough into the ground around the edges of the tarps. Alternatively, the edges of the tarps could be fabricated to form pockets which can be filled with water such that the tarp can be held in position during operation, and then drained for transport and storage.

An advantage of the present covering or tarping systems are that they create a highly-controlled temperature and humidity environment in turf grass region 10 and may be left in position for several hours, as desired. Ideally, such tarps would most suitably be used at night or during other occasions when the golf green was unavailable for play.

In prefeπed aspects the present coverings are positioned a region of the turf grass green 10 such that they extend beyond the green surface proper, to include the fringe and green apron, thus reducing the spread of poa annua from areas immediately adjacent to the green, thereby combating the spread of poa annua by wind migration and foot transport.

Preferably, the temperature and humidity conditions under the covering system would be under thermostatic and optional humidity regulator control and would be monitored by appropriate thermometers and sensors, such that desired temperature and humidity levels can be maintained in near-optimal conditions. In prefeπed aspects, the thermostatic regulator control maintains the temperature under the tarp between 115°F and 120°F for about 2 hours.

Referring to Fig. 5, a sectional domed covering 50, which may be made of a plurality of sections 52 which may be assembled by hook and loop (e.g.: Velcro) fasteners around their perimeter, or any other suitable fastening systems 54. A portable microclimate control system 60 (which may comprise any or all of a fan, a heater, an air conditioner, a heat pump, a humidifier, a dehumidifier, a temperature sensor, a humidity sensor and an electrical generator) may be used to control the climate under domed covering 50. In addition to controlling undesirable plant growth and insect and fungal infestations, the microclimate under domed covering 50 may be used to provide a temporary and portable enclosure for public events, homeless shelters, military baπacks, etc. A plurality of water or sand filled bags 56 (or an ring shaped bag) disposed around the perimeter of domed covering 50 can be used to hold domed covering 50 in position during treatment of the vegetative covering thereunder.

Claims

WHAT IS CLAIMED IS: 1. A method for suppressing undesirable plant growth, comprising: isolating a region of vegetative cover from a suπounding environment; varying at least one of the temperature and humidity of the isolated region, whereby undesirable plant growth is suppressed, yet desirable plant growth is not substantially suppressed.

2. The method of claim 1, wherein the variance in the temperature or humidity causes a greater damage to the undesirable plant species than to the desirable plant species.

3. The method of claim 1 , wherein the variance in the temperature or humidity causes a reduction in insect infestations.

4. The method of claim 1 , wherein the variance in the temperature or humidity causes a reduction in the viability of plant pathogens.

5. The method of claim 1, wherein the undesirable plant comprises poa annua.

6. A method of eradicating poa annua, comprising: isolating a region of turf grass comprising bentgrass and poa annua from an ambient environment; and increasing the temperature of the isolated region to a temperature which detrimentally affects the poa annua plant or the viability of its seed, yet does not detrimentally affect the bentgrass.

7. The method of claim 6, further comprising: increasing the humidity of the isolated region to a humidity which detrimentally affects the poa annua plant or the viability of its seed, yet does not detrimentally affect the bentgrass.

8. The method of claim 6, wherein, the temperature is increased to the range of 115°F to 120°F.

9. The method of claim 8, wherein, the temperature is maintained in the range of 115°F to 120°F for about 2 hours.

10. A microclimate isolation system, comprising: a ground covering adapted to alter at least one of the temperature or humidity of a region of vegetative cover disposed thereunder.

11. The microclimate isolation system of claim 10, further comprising: a temperature control system.

12. The microclimate isolation system of claim 10, wherein the temperature control system comprises a heating system.

13. The microclimate isolation system of claim 10, wherein the temperature control system comprises a cooling system.

14. The microclimate isolation system of claim 10, further comprising: a humidity control system.

15. The microclimate isolation system of claim 10, wherein the ground covering is a tarp.

16. The microclimate isolation system of claim 15, wherein the tarp is a domed tarp

17. The microclimate isolation system of claim 10, wherein the ground covering is secured to the ground by water filled bags around its perimeter

18. The microclimate isolation system of claim 10, wherein the ground covering comprises a plurality of separately attachable sections.

19. The microclimate isolation system of claim 18, wherein the attachable sections are held together by hook and loop fasteners.

20. The microclimate isolation system of claim 18, wherein the attachable sections are held together by zippers.

21. A device for eradicating poa annua, comprising: a tarp for isolating a region of turf grass comprising bentgrass and poa annua from an ambient environment.

22. The device of claim 21 , further comprising: an electrical heating system disposed within the tarp.

23. The device of claim 21, further comprising: a fluid heating system disposed within the tarp.

24. The device of claim 21, further comprising: a forced air heating system adapted to blow heated air under the tarp.

25. The device of claim 21, further comprising: a temperature monitoring system for measuring the temperature in the isolated region under the tarp.

26. The device of claim 21, further comprising: a temperature control system for regulating the temperature in the isolated region below the tarp.

27. The device of claim 21 , further comprising: a humidity monitoring system for measuring the humidity in the isolated region below the tarp.

28. The device of claim 21, further comprising: a humidity control system for regulating the humidity of the isolated region of turf grass.