JP2016073230A - Weed control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a weed control method capable of getting rid of hard-to-kill weeds such as kuzu vines.SOLUTION: The weed control method achieves, by using ultraviolet light, at least one of killing creeping weeds that are hard to kill and the growth control. For example, the ultraviolet light is directly applied to the hard-to-kill weeds to kill the hard-to-kill weeds, or the ultraviolet light is applied to a space in which intrusion of the hard-to-kill weeds should be avoided to control the growth of the hard-to-kill weeds. The weed control method for the creeping weeds that are hard to kill, kills and controls the growth of the hard-to-kill weeds.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a herbicidal method for killing or controlling growth of difficult-to-control weeds that are difficult to control.

Conventionally, as a method for killing weeds or suppressing the growth of weeds, a method in which an operator mechanically cuts the weeds or kills the weeds using a herbicide is used.
However, there are a large number of places where weeds are required to be treated (places where weed intrusion should be avoided). Therefore, when workers perform mechanical mowing, a large number of workers are required. Processing man-hours become enormous. In addition, the method using herbicides exhibits a high herbicidal effect, but there is a risk of causing phytotoxicity to useful crops that are not subject to herbicidal protection due to scattering by wind during spraying or flowing into the water system due to rainfall after spraying. At the same time, there is a risk of adverse effects on fish and other wildlife.

  Therefore, as a method for killing weeds or suppressing growth without mechanical mowing or spraying of a herbicide by an operator, there is a technique described in Patent Document 1, for example. This technique is a method of irradiating weeds with artificial ultraviolet rays to kill or suppress the growth of the weeds. Specifically, a high herbicidal effect can be obtained by irradiating near-ultraviolet light (UV-B) having a wavelength of 280 nm to 315 nm with respect to cotyledons of leguminous mungbeans and various broad-leaved species with wide leaves. It is disclosed.

JP 2011-205962 A

However, the technique described in Patent Document 1 merely demonstrates the effectiveness of the herbicidal effect as a test weed using various broad-leaved species such as mungbean cotyledons and purslane. No consideration is given to the control of difficult control weeds.
For example, a vine perennial that belongs to the genus Kudu (hereinafter simply referred to as “kuzu”) may wrap around a branch of a tree that has just started to grow, causing the branch of the tree to bend. For this reason, planted forests are often recognized as harmful plants that hinder the growth of young trees. In addition, when not cutting, the kudzu grows fast enough to cover the shrub forest in a short period of time, and since it is a perennial that grows with the rhizome, the rhizome remains in the basement immediately after cutting the vine on the ground. Since the vine regenerates, it is very difficult to remove it once grown. For these reasons, waste is recognized as a difficult-to-control weed.

The weed species disclosed as being able to obtain the herbicidal effect by the above-mentioned conventional methods are weeds having a plant height of about several tens of centimeters when not irradiated with ultraviolet light. For this reason, there is a possibility that a high herbicidal effect may not be obtained for vine-resistant difficult-to-control weeds that grow on underground rhizomes such as scraps and have a maximum plant height of several tens of meters.
Then, this invention makes it a subject to provide the weed control method which can control hard-to-control weeds, such as a waste, appropriately.

In order to solve the above-described problems, one aspect of the herbicidal method according to the present invention realizes at least one of killing and controlling the growth of vine difficult-to-control weeds using ultraviolet rays.
In this way, vine-type difficult-to-control weeds are targeted for weed control, and killing and growth control of the difficult-to-control weeds are realized. Therefore, it is possible to prevent difficult-to-control weed vines from being wrapped around useful plants, or to prevent human safety, comfort, convenience, and the like from being hindered by the growth of the difficult-to-control weeds.
Furthermore, in the above-described weed control method, the weed invasion avoidance space, which is a space where invasion of the difficult to control weeds should be avoided, is irradiated with the ultraviolet rays that can obtain the intrusion prevention phenomenon of the difficult to control weeds. Also good.

  Thereby, the growth of the difficult-to-control weeds that grow outside the weed invasion avoidance space can be controlled, and the inevitable weeds can be prevented from entering the weed invasion avoidance space. In this way, it is possible to control the growth of difficult-to-control weeds without directly irradiating the difficult-to-control weeds with ultraviolet rays. Therefore, for example, if the space where the facility structure exists is set as a weed invasion avoidance space, it is possible to prevent the function of the facility structure from being impaired due to the invasion of difficult-to-control weeds. Moreover, if the space in the vicinity of the facility structure is set as a weed invasion avoidance space, it is possible to prevent the operation of the facility structure from being hindered by the invasion of weeds.

Further, in the above weed control method, in the state where the difficult control weeds do not appear on the ground surface in the vicinity of the weed invasion avoidance space, which is a space where the invasion of the difficult control weeds should be avoided, You may make it irradiate the said ultraviolet-ray from which the penetration | invasion prevention phenomenon of difficult-to-control weeds is obtained.
Thereby, it is possible to prevent difficult-to-control weeds (hard-to-control weeds before appearing on the ground surface) existing in the basement near the weed invasion avoidance space from appearing on the ground surface. In addition, in the process in which vine-type difficult-to-control weeds grow on the ground surface, they can be grown while avoiding the ground surface near the weed invasion avoidance space. In this way, it is possible to control the growth of difficult-to-control weeds without directly irradiating the difficult-to-control weeds with ultraviolet rays. Therefore, it is possible to effectively suppress difficult-to-control weeds from entering the weed invasion avoidance space.

Furthermore, even when difficult-to-control weeds are already proliferating in the weed invasion avoidance space, weed invasion avoidance can be achieved by directly irradiating the difficult-to-control weeds with the ultraviolet rays that can kill the difficult-to-control weeds. The dual effect of killing the weeds that originally grew in the space and preventing the difficult-to-control weeds from entering the weed invasion avoidance space can be obtained.
Moreover, in the above-mentioned herbicidal method, the above-mentioned ultraviolet rays that can obtain the killing effect of the difficult-to-control weeds may be directly irradiated to the difficult-to-control weeds. Thereby, the difficult-to-control weeds that are the target of herbicidal protection can be effectively killed.

Furthermore, in the above-mentioned herbicidal method, the above-mentioned ultraviolet rays that can obtain the killing effect of the difficult-to-control weeds may be directly irradiated to the difficult-to-control weeds in the initial growth stage. In this way, by directly irradiating ultraviolet rays to difficult-to-control weeds in the early stages of growth, without requiring large-scale facilities (a large number of UV light sources and their power sources) Can be effectively killed.
Further, in the above weed control method, the difficult-to-control weeds may be weeds having a plant height of at least 1 m during normal growth. In this way, a high herbicidal effect can be obtained even for weeds having a strong fertility such that the plant height during growth is 1 m or more.

In the above weed control method, the difficult-to-control weeds may be kudzu. In this way, a high herbicidal effect can be obtained even for vigorous conflict of fertility such that the plant height reaches several tens of meters at an early stage.
Furthermore, in the above herbicidal method, the ultraviolet ray may have a wavelength of 200 nm or more and 280 nm or less. As described above, by using ultraviolet rays (UV-C) having a wavelength of 200 nm or more and 280 nm or less, it is possible to effectively kill and control growth of difficult-to-control weeds.

Moreover, in the above-mentioned herbicidal method, the ultraviolet light may have a wavelength at which the light emission intensity is maximum near 230 nm. For example, if a rare gas fluorescent lamp enclosing xenon gas is used, ultraviolet light having a peak wavelength of 230 nm and a continuous spectrum in the wavelength range of 200 nm to 280 nm can be obtained. In this way, a high herbicidal effect on difficult-to-control weeds can be obtained using a practical light source.
Furthermore, one embodiment of the herbicidal method according to the present invention realizes at least one of plant killing and growth control using ultraviolet rays having a wavelength of 200 nm to 280 nm.
Thus, by using ultraviolet rays (UV-C) having a wavelength of 200 nm or more and 280 nm or less, plant death and growth control can be effectively performed.

  In the herbicidal method of the present invention, vine-resistant difficult-to-control weeds are targeted for herbicidal protection, and the killing and growth control of the difficult-to-control weeds can be effectively realized using ultraviolet rays. Therefore, it is possible to prevent damage caused by difficult-to-control weeds having a strong fertility.

It is a figure which shows an example of the weed prevention method in this embodiment. It is a figure which shows wavelength distribution of the light radiated | emitted from a lamp | ramp. It is a figure which shows the state of the experiment first day at the time of UV irradiation with respect to a scrap. It is a figure which shows the experimental result in the case of UV irradiation. It is a figure which shows the state of the experiment first day at the time of irradiating UV with respect to the earth surface where the waste does not appear. It is a figure which shows the state of the experiment first day at the time of irradiating UV with respect to the waste in the early stage of growth. It is a figure which shows the state of the experiment first day in the case of no UV irradiation. It is a figure which shows the experimental result in the case of no UV irradiation.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a diagram illustrating an example of a weed control method according to this embodiment.
In the present embodiment, the ultraviolet rays radiated from the ultraviolet irradiation device 10 are used to irradiate the difficult-to-control weeds 21a by irradiating the difficult-to-control weeds 21a, or to grow outside the ultraviolet irradiation space S where the ultraviolet rays are irradiated. The growth control of the difficult-to-control weeds 21b is performed.
Here, the difficult-to-control weeds 21a, 21b are weeds that are generally recognized as difficult to control in farmland, forest land, public transportation, public facilities, etc., and are usually left without carrying out various kinds of weed control means. This refers to vine weeds that grow to a height of 1m or more (up to several tens of meters). As the difficult-to-control weeds 21a and 21b, for example, there is kuzu (hereinafter simply referred to as “kuzu”) which belongs to the genus Leguminosae and is a vine perennial.
In addition, in this specification, the plant height of a vine difficulty difficult-to-control weed means the vertical direction full length of this structure in the state which stuck to the structure etc.

The ultraviolet irradiation device 10 includes an ultraviolet light source (lamp) 11 and a controller 12.
The lamp 11 emits ultraviolet rays that can kill or control the growth of difficult-to-control weeds. Here, the ultraviolet rays emitted from the lamp 11 are, for example, ultraviolet rays (UV-C) having a wavelength of 200 nm to 280 nm.
For example, as the lamp 11, as shown in FIG. 2, a rare gas fluorescent lamp having a wavelength (peak wavelength) at which the emission intensity is maximum is 230 nm and has a continuous spectrum in the wavelength range of 200 nm to 280 nm is used. it can. In FIG. 2, the horizontal axis represents wavelength λ [nm], and the vertical axis represents emission intensity I (arbitrary unit). Here, the rare gas fluorescent lamp is made of quartz glass, and is formed on the inner surface of the arc tube with a discharge tube containing a discharge gas containing xenon inside, a pair of electrodes arranged outside the arc tube. A fluorescent lamp.

The controller 12 controls the irradiation conditions such as the irradiation timing, irradiation time, irradiation intensity [μW / cm ² ], irradiation amount [J / cm ² ] of the ultraviolet rays irradiated from the lamp 11 to the difficult-to-control weed 21a.
In addition, the irradiation conditions of ultraviolet rays are appropriately set according to the kind of difficult-to-control weeds to be protected. In particular, since UV-C irradiation may adversely affect the human body, the controller 12 controls the lamp 11 so that UV-C irradiation is performed in a time zone in which an operator or the like does not enter the ultraviolet irradiation space S. Shall.

For example, when not cutting, the scrap grows until the shrub forest is covered in a short period of time. In addition, because Kudzu is a perennial that grows by rhizomes, even if the vines on the above-ground part are cut off, the rhizomes remain in the basement, and the vines immediately regenerate. Therefore, it is very difficult to remove them once they grow.
When wrapping around a branch of a tree that has just begun to grow, the branch of the tree may bend, which is often recognized as a harmful plant that hinders the growth of young trees in planted forests.

In addition to the above-mentioned artificial forests, there is a problem that damage is caused by scrapes on various devices such as public transportation. Scraps are vines, and the plant height when growing reaches several tens of meters or more. For example, the visibility of traffic lights etc. is impaired by hitting the traffic lights of various transportation facilities such as trains and highways. Safety is impeded.
In addition, there is a concern that scrapes of infrastructure such as factory pipelines and power transmission line towers may impair their original functions or hinder inspection and management. In addition, in public facilities such as parks and green spaces, the proliferation of debris hinders comfort as a place of relaxation, and the lighting function is impaired due to the debris spreading on streetlights, especially at night. There are problems such as worsening.

Although measures against herbs, herbicides, herbicidal sheets and mowing are taken, it is difficult to say that sufficient measures are currently being taken. First of all, Kudzu is a difficult-to-control weed with low herbicidal effectiveness, and the adverse effects on the ecosystem cannot be ignored if a herbicidal method of spraying the herbicide is selected.
In addition, there is a concern that the herbicidal sheet is scattered by strong winds and adheres to a power transmission line or the like, and further, it takes time and cost to process a used cover. Mowing uses mechanical means such as mowers and riding mowers, but handles sharp blades that rotate at high speeds, so there is a risk of injury to workers and a continuous human cost. There is also a negative environmental aspect that uses fossil fuels and has a large environmental impact.

Therefore, in the present embodiment, UV-C is irradiated to difficult-to-control weeds such as scraps. Thereby, without taking measures by a herbicide, a herbicidal sheet, and mowing, the difficult-to-control weeds are killed or controlled for growth, and the difficult-to-control weeds are effectively controlled.
In order to confirm the killing effect when directly irradiating ultraviolet rays (UV-C) to difficult-to-control weeds, the growth state of scum with and without ultraviolet irradiation was observed.

FIG. 3 shows the state of the first day of the experiment with ultraviolet irradiation. As shown in FIG. 3, ultraviolet rays (UV-C) were irradiated to the ultraviolet irradiation space S under preset irradiation conditions in a state where the scraps 21a and 21b were prosperous. That is, the waste 21a existing in the ultraviolet irradiation space S was irradiated with UV-C, and the waste 21b adjacent to the scrap 21a was not irradiated with UV-C.
Here, the irradiation conditions were an irradiation intensity of 200 μW / cm ² (irradiance at a position 600 mm from the center of the irradiation range A) and an irradiation amount of 0.7 J / cm ² per day. Further, the irradiation range A on the ground in FIG. 1 is 1 m × 1 m or more, and the irradiation distance D from the lamp 11 to the ground is 450 mm.

And it continued to irradiate only the waste 21a with UV-C for a predetermined period, and the growth situation of the subsequent waste 21a, 21b was confirmed. The result is shown in FIG.
As shown in FIG. 4, the waste 21a irradiated with UV-C was killed, and only the waste 21b outside the ultraviolet irradiation space S continued to grow. Further, the scum 21b outside the ultraviolet irradiation space S grew while avoiding the space irradiated with UV-C, and did not penetrate into the ultraviolet irradiation space S irradiated with UV-C.
Thus, it was confirmed that a high killing effect can be obtained by directly irradiating UV-C to the waste which is difficult to control. Further, it was confirmed that the growth control was possible for the scraps outside the ultraviolet irradiation space S.

Furthermore, in order to confirm the killing effect of difficult-to-control weeds by UV-C irradiation, UV-C was irradiated to the various weeds under the same conditions, and the inhibition rate was investigated. Here, the irradiation conditions were the same as those in the experiment of FIG.
The inhibition rate is a mass ratio between the test weed after the ultraviolet irradiation and the untreated test weed. That is, the inhibition rate of 0% means that the treated and untreated ones are exactly the same, and the greater the inhibition rate, the greater the herbicidal effect by ultraviolet irradiation. .

  As the test weeds, in addition to the kudu which is an example, bark beetle, Ezogoshigishi, oyster millet, crows pea, and kochakobe were used as comparative examples. As a result of investigating the inhibition rate of these various weeds, when UV-C having a wavelength of 200 nm to 280 nm is irradiated, a high inhibition rate is obtained in the waste, but the inhibition rate in various weeds other than the waste is compared with the inhibition rate in the waste. It turned out to be low. Thus, it was found that the ultraviolet light having a wavelength of 200 nm to 280 nm is an ultraviolet light having a high killing effect on difficult-to-control weeds such as kudzu.

From the above, it can be said that irradiating ultraviolet light having a specific wavelength (wavelength 200 nm to 280 nm) to the difficult-to-control weeds is an effective herbicidal method for the difficult-to-control weeds. Therefore, by directly irradiating the difficult-to-control weeds with ultraviolet light having the above-mentioned wavelength, even if the ultraviolet light is subsequently irradiated to the overgrown difficult-to-control weeds, the difficult-to-control weeds can be effectively killed. Can do.
In this way, the difficult-to-control weeds can be targeted for weed control, and the difficult-to-control weeds can be appropriately killed. Therefore, it is possible to prevent difficult-to-control weed vines from being wrapped around useful plants, or to prevent human safety, comfort, convenience, etc. from being hindered by the over-exploited weeds.

However, it is preferable to prevent overgrowth of difficult-to-control weeds with vigorous fertility that reach an early plant height of several tens of meters. When weeds with high reproductive potential grow up to reach several tens of meters long, such as trash, large facilities (multiple UV light sources and their power sources) are required to kill them, and weeding costs This is because of the increase.
Therefore, in order to prevent overgrowth of difficult-to-control weeds, the above-mentioned difficult-to-control weeds do not appear on the ground surface, or even if they appear, the plant height is low at the initial stage of growth (for example, less than 1 mm in plant height). It is preferable to irradiate the difficult-to-control weeds with ultraviolet light having a wavelength.

In FIG. 5, UV-C is irradiated from a lamp 11 to a specific ultraviolet irradiation space (including the ground surface) S in a state where there is a waste rhizome 21c in the basement but no waste appears on the ground surface. The state of the experiment on the first day.
From this state, UV-C was continuously applied to the ultraviolet irradiation space S, and the growth state of the scrap was confirmed. Then, as shown in FIG. 4, no debris appeared from the surface irradiated with ultraviolet rays, and the debris 21b grew only outside the ultraviolet irradiation space S. Further, the waste 21b grown outside the ultraviolet irradiation space S did not enter the ultraviolet irradiation space S.
In this way, when the difficult-to-control weeds do not appear on the ground surface, the difficult-to-control weeds can be prevented from appearing on the ground surface by irradiating the surface with UV-C. That is, it is possible to control the growth of difficult-to-control weeds existing under the surface (underground) irradiated with UV-C.

Further, FIG. 6 shows the state of the first day of experiment when UV-C is irradiated from the lamp 11 only to the scrap 21a among the scraps 21a and 21b in the early stage of growth. From this state, only the waste 21a was continuously irradiated with UV-C, and the growth status of the wastes 21a and 21b was confirmed. Then, the waste 21a irradiated with UV-C was easily killed, and only the waste 21b not irradiated with UV-C grew as shown in FIG. Further, the waste 21b did not enter the ultraviolet irradiation space S.
In this way, by directly irradiating the difficult-to-control weeds with UV-C at the early stage of growth, it is relatively easy compared to the case of irradiating the over-expensive difficult-to-control weeds afterwards with ultraviolet light The controllable weeds can be killed. That is, it is possible to effectively kill difficult-to-control weeds without requiring large-scale facilities, and to reduce the weeding cost.

As a comparative example, the growth state of the waste when UV-C irradiation was not performed in the same environment as FIG. 6 was confirmed. FIG. 7 shows the state of the first day of the experiment when UV-C irradiation is not performed in the same environment as FIG. From this state, the growth situation of the scraps 21a and 21b after about two and a half months was confirmed. The result is shown in FIG.
As shown in FIG. 8, both the waste 21 a in the ultraviolet irradiation space S irradiated with ultraviolet rays in the experiment of FIG. 6 and 21 b outside the ultraviolet irradiation space S grow, and the scrap 21 b is in the ultraviolet irradiation space S. Invaded. Thus, when UV-C is not irradiated, the phenomenon that the waste 21b in which the rhizome does not exist underground in the ultraviolet irradiation space S enters the ultraviolet irradiation space S occurs.

  From the above, it was confirmed that the difficult-to-control weeds grew while avoiding the UV-C irradiation space. That is, it can be said that the ultraviolet light having a wavelength of 200 nm to 280 nm is an ultraviolet light capable of obtaining an invasion preventing phenomenon against difficult-to-control weeds such as kudzu. Therefore, if the space (weed invasion avoidance space) that should avoid the invasion of difficult control weeds is set as the ultraviolet irradiation space S and irradiated with UV-C, the growth of the difficult to control weeds growing outside the weed invasion avoidance space is controlled. Invasion of the difficult-to-control weeds into the weed invasion avoidance space can be avoided.

The weed invasion avoidance space is, for example, “the function of facility structures (industrial facilities, transportation facilities, public facilities, etc.) is impaired due to the invasion of difficult-to-control weeds, or the operation of the facility structures is hindered. Space ”.
Industrial facilities include, for example, power generation facilities such as solar panels, meteorological measurement facilities such as oil pipelines and anemometers. For solar panels, power generation efficiency decreases when sunlight is shielded by overgrown weeds. For oil pipelines, weeds may grow and hinder inspection and management. Furthermore, with regard to the anemometer, if the rotation of the wind cup is hindered by overgrown weeds, it will hinder the detection of the wind speed. Therefore, for industrial facilities, a space for irradiating the solar panel, an inspection work space for the oil pipeline, a space necessary for the rotation operation of the anemometer, and the like are set as a weed invasion avoidance space.

  Examples of traffic facilities include road intersections, traffic lights, traffic signs, and the like. Overgrowth of weeds that hinder the visibility of drivers and pedestrians at road intersections impedes traffic safety. Also, when the weeds grow over the road fence and the visibility of road signs and traffic lights is reduced by the weeds, the traffic safety is similarly inhibited. Therefore, for traffic facilities, a space where a driver's or pedestrian's view should be secured is set as a weed invasion avoidance space so that traffic lights and traffic signs can be visually recognized.

Furthermore, public facilities include street lamps such as parks and green spaces. As for streetlights, lighting functions are impaired when overgrown weeds grow, and there is concern over deterioration of security at night. Therefore, for public facilities, the space where the lighting part of the street lamp exists is set as a weed invasion avoidance space.
As described above, the weed invasion avoidance space includes a space where the facility structure exists and a space near the facility structure.
By setting the weed invasion avoidance space as described above, for example, it is difficult to see traffic lights, obstructs safety due to poor visibility of automobile drivers and pedestrians, and lowers power generation efficiency due to reduced sunlight irradiation on the solar panel And problems such as obstacles to the inspection and management of the oil pipeline can be solved.
Accordingly, it is possible to prevent human safety, comfort, convenience, and the like from being hindered by the growth of difficult-to-control weeds.

In addition, as described above, when the weed invasion avoidance space is set at a position away from the ground surface, the difficult control weeds do not appear on the ground surface in the vicinity of the weed invasion avoidance space. By irradiating UV-C, it is possible to prevent the difficult-to-control weeds from entering the weed invasion avoidance space.
As described above, when UV-C is irradiated on the ground surface before the difficult-to-control weeds appear, the difficult-to-control weeds do not appear from the surface. In addition, vine-type difficult-to-control weeds grow on the ground in spaces where there are no trees or facility structures. For example, Kudzu roots from a node where a vine hits the ground and touches the ground. In this way, the vine-type difficult-to-control weeds that have grown on the ground grow upward when they come into contact with trees or facility structures. Therefore, if UV-C is irradiated to the ground surface near the weed invasion avoidance space, the difficult-to-control weed grows avoiding the UV-C irradiated ground surface and cannot enter the weed invasion avoidance space.
Thus, irradiating the weed invasion avoidance space or the surface near the weed invasion avoidance space with UV-C and preventing the invasion of difficult to control weeds into the space is an effective weed control method for difficult to control weeds. It is.

As described above, in the present embodiment, the vine-resistant difficult-to-control weeds are irradiated with ultraviolet rays that can obtain the killing effect of the refractory-controlling weeds, or spaces that should avoid the invasion of the vine-proof difficult-to-control weeds By irradiating ultraviolet rays that can prevent the invasion of the difficult-to-control weeds or the surface of the vicinity thereof, the vine-type difficult-to-control weeds are killed or controlled for growth.
Here, the ultraviolet rays are ultraviolet rays having a wavelength of 200 nm to 280 nm (UV-C) that can realize the killing of the difficult-to-control weeds and the prevention of invasion. Thereby, a high herbicidal effect can be obtained with respect to difficult-to-control weeds. That is, in a state where difficult-to-control weeds exist in a space where invasion of the difficult-to-control weeds is present, when the space is irradiated with UV-C, the killing of the difficult-to-control weeds growing in the space, It is possible to simultaneously prevent invasion of difficult-to-control weeds that grow outside the space.

Moreover, the said ultraviolet-ray shall be UV-C whose peak wavelength is 230 nm. Therefore, for example, a high herbicidal effect on difficult-to-control weeds can be obtained by using a practical light source such as a rare gas fluorescent lamp enclosing xenon gas.
As described above, the grass prevention method according to the present embodiment, when left without performing various grass protection means, reaches a maximum of 1 m or more and reaches a structure in public transportation or public facilities. Thus, it is useful as a herbicidal method for vine-resistant difficult-to-control weeds that have a strong fertility and are likely to impair the function of the structure.

(Modification)
In addition, in the said embodiment, although the case where UV-C whose peak wavelength is 230 nm was radiated | emitted from the ultraviolet light source of the ultraviolet light irradiation apparatus 10 was demonstrated, a high herbicidal effect will be acquired if it is wavelength 200nm -280nm. Therefore, the peak wavelength is not limited to 230 nm.
Furthermore, the ultraviolet rays radiated from the ultraviolet light source may be ultraviolet rays that can obtain the effect of killing difficult-to-control weeds or the invasion prevention phenomenon. For example, UV-B having a wavelength of 280 nm to 315 nm can be used as the ultraviolet rays that can prevent the invasion of difficult-to-control weeds. However, among the near-ultraviolet light, the method of irradiating ultraviolet rays in the UV-C region can most effectively generate the invasion prevention phenomenon of difficult-to-control weeds and also has a high killing effect on the difficult-to-control weeds. The ultraviolet rays emitted from the ultraviolet light source are preferably ultraviolet rays in the UV-C region.

  Further, in the above embodiment, a case where a rare gas fluorescent lamp is applied as an ultraviolet light source has been described. Applicable. For example, various ultraviolet light sources such as an excimer lamp, a mercury lamp, a laser diode, and an LED can be used as the ultraviolet light source.

  DESCRIPTION OF SYMBOLS 10 ... Ultraviolet irradiation apparatus, 11 ... Lamp, 12 ... Controller, 21a, 21b ... Difficult to control weed (Kudzu), A ... Irradiation range, D ... Irradiation distance, S ... Ultraviolet irradiation space (weed invasion avoidance space)

Claims (10)

  A herbicidal method characterized in that at least one of eradication and growth control of vine difficult-to-control weeds is realized using ultraviolet rays.   2. The weed prevention according to claim 1, wherein the weed invasion avoidance space, which is a space where invasion of the difficult to control weeds, should be avoided, is irradiated with the ultraviolet rays that provide the intrusion prevention phenomenon of the difficult to control weeds. Method.   In the state where the difficult-to-control weeds do not appear on the ground surface in the vicinity of the weed invasion avoidance space, which is a space where invasion of the difficult-to-control weeds should be avoided, the intrusion prevention phenomenon of the difficult-to-control weeds is obtained on the surface. The herbicidal method according to claim 1, wherein the ultraviolet ray is irradiated.   2. The herbicidal method according to claim 1, wherein the ultraviolet rays that directly obtain the killing effect of the difficult-to-control weeds are directly irradiated to the difficult-to-control weeds.   The herbicidal method according to claim 4, wherein the ultraviolet rays that directly obtain the killing effect of the difficult-to-control weeds are directly irradiated to the difficult-to-control weeds in the initial growth stage.   The weed control method according to any one of claims 1 to 5, wherein the difficult-to-control weeds are weeds that reach a height of at least 1 m during normal growth.   The weed control method according to claim 6, wherein the difficult-to-control weeds are kudzu.   The said ultraviolet-ray has a wavelength of 200 nm or more and 280 nm or less, The weed prevention method of any one of Claims 1-7 characterized by the above-mentioned.   The weed prevention method according to claim 8, wherein the ultraviolet light has a wavelength at which the light emission intensity becomes maximum at around 230 nm. A herbicidal method characterized in that at least one of plant killing and growth control is realized using ultraviolet light having a wavelength of 200 nm to 280 nm.

Images