Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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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.
TECHNICAL 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
ar~nua 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
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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
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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
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covering. Thereafter, either or both of the temperature and/or humidity are
elevated to
preferred 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 paa 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 l I5°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
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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
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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 preferred 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 preferred
aspects, the
thermostatic regulator control maintains the temperature under the tarp
between 115°F and
120°F for about 2 hours.
Refernng 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
1 S 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 S0. 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 barracks, 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.
