Method of using simazine to control annual bluegrass in cool-season turfgrasses

Abstract

A method is disclosed for using simazine to control and reduce the formation of flowers and seed heads in turfgrasses, including cool-season turfgrasses, and to suppress the growth of annual bluegrass (Poa annua). The method comprises applying an effective dose of simazine to the turfgrasses. A method is also disclosed for enhancing the color and quality of cool-season turfgrasses as a result of a penox slam treatment applied to turfgrasses, including cool-season turfgrasses. The method comprises applying an effective dose of simazine to the turfgrasses. A method for selectively controlling barnyard grass (Paspalum vaginatum) in turfgrasses, including Bermuda grass, is further disclosed, the method comprising applying an effective dose of simazine to the turfgrasses.

Description

Technical Field

[0001] Cross - Reference to Related Applications This application claims the priority and benefit of U.S. Provisional Patent Application No. 63 / 454,046, filed on March 22, 2023, entitled "A METHOD OF USING SIMAZINE FOR CONTROLLING ANNUAL BLUEGRASS IN COOL - SEASON TURFGRASSES" and U.S. Utility Patent Application No. 18 / 613,069, filed on March 21, 2024, entitled "A METHOD OF USING SIMAZINE FOR CONTROLLING ANNUAL BLUEGRASS IN COOL SEASON - TURFGRASSES", and the entire disclosures of these are incorporated herein by reference.

[0002] This document relates to a method of using simazine for controlling annual bluegrass in cool - season turfgrasses.

Background Art

[0003] Turfgrasses classified as warm - season species evolved in hot, subtropical or tropical climates. These grow well in hot and humid climates and become dormant or even die in cold climates. Non - limiting examples of warm - season species include bermudagrass, zoysia grass, and Japanese lawngrass. On the other hand, cool - season turfgrass species evolved in the northern temperate or cool climates. Therefore, they grow well in medium temperatures and survive in low temperatures. Some have difficulty surviving in hot and humid climates and can even enter a dormant state to avoid lethal temperatures. Non - limiting examples of cool - season turfgrasses are Kentucky bluegrass, ryegrass, bentgrass, and fescue.

[0004] The invasion of turfgrasses by the weed Poa annua is a significant problem for turfgrass managers in most parts of the world. As an annual plant, it rapidly germinates, grows, produces abundant seeds, and dies throughout its entire life cycle. Furthermore, some biotypes of this species are actually perennial, meaning they are adapted to favorable environments and survive as perennial plants, not dying at programmed times throughout the year. Poa annua is classified as a cold-climate species, meaning it evolved in the temperate northern climate and is best adapted to this climate. Poa annua is a weed with little tolerance for high temperatures, and therefore has low survival rate in summer.

[0005] Poa annua is visually unsightly and, during its flowering and seed-producing periods throughout the year, negatively impacts the surface performance of turfgrass (e.g., ball roll on a golf course). Poa annua often invades warm-season turfgrasses. This is especially true in cool climates where warm-season turfgrasses are not strongly competing and may even be dormant. Simultaneously, the low temperatures make Poa annua a highly competitive weed. Thus, active invasion of desired turfgrass species by Poa annua occurs. Many herbicides can utilize different growth patterns and other distinct metabolic characteristics to selectively damage or kill Poa annua while substantially harming the desired warm-season species. These herbicides are well known and marketed for this purpose.

[0006] The herbicide simazine is currently used for selective weed control in crops, particularly corn, but its use for weed control in cool-season turfgrasses such as ryegrass, bentgrass, and fescue is unknown. [Overview of the Initiative]

[0007] One embodiment discloses a method for using simazine to control annual bluegrass (Poa annua) in turfgrasses, including cool-season turfgrass species. This method involves applying an effective dose of simazine to the turfgrass. The effective dose of simazine does not cause unacceptable damage to the cool-season turfgrass species.

[0008] Implementation may include one or more, or all of the following:

[0009] In some embodiments, an effective dose of simazine inhibits the growth of annual bluegrass in turfgrasses, including cool-season turfgrass species.

[0010] Cool-season turfgrass species include rye, bentgrass, or fescue.

[0011] Cool-season turfgrass species are rye, and the effective dose of simazine is approximately 0.01 lb AI / A to approximately 1.0 lb AI / A.

[0012] The effective dose of simazine is approximately 0.01 lb AI / A to 0.25 lb AI / A or approximately 0.05 lb AI / A to 0.25 lb AI / A. Simazine is administered at least twice, with each administration separated by at least one week, for example, approximately one to four weeks or three weeks. Simazine is administered two or three times.

[0013] The effective dose of simazine is approximately 0.25 lb AI / A to approximately 0.5 lb AI / A. Simazine is administered up to two times, with each administration separated by at least one week, for example, approximately 1 to 4 weeks or approximately 3 weeks. For example, simazine may be administered only once at the effective dose of approximately 0.25 lb AI / A to approximately 0.5 lb AI / A.

[0014] The effective dose of simazine is approximately 0.05 lb AI / A to 1.0 lb AI / A. Simazine is administered as a single dose.

[0015] In another embodiment, a method is disclosed for using simazine to reduce the formation of flowers and seed heads in Poa annua. The method involves the application of an effective dose of simazine to Poa annua. The effective dose of simazine is the sublethal dose of simazine for Poa annua.

[0016] Implementation may include one or more, or all of the following:

[0017] Annual bluegrass is grown in a turfgrass containing cool-season turfgrass species. The cool-season turfgrass species are rye, bentgrass, or fescue. The effective dose of simazine is the sublethal dose of simazine for both annual bluegrass and the aforementioned cool-season turfgrass species.

[0018] The effective dose of simazine is approximately 0.25 lb AI / A.

[0019] In yet another embodiment, a method for enhancing the color and quality of turfgrass, including cool-season turfgrass species, is disclosed. This method includes applying an effective dose of simazine to the turfgrass.

[0020] Implementation may include one or more, or all of the following:

[0021] Cool-season turfgrass species include rye, bentgrass, or fescue.

[0022] An effective dose of simazine is simultaneously administered to the lawn along with a herbicide, such as penoxulam.

[0023] The effective dose of simazine to be administered is approximately 0.05 lb AI / A to approximately 0.25 lb AI / A.

[0024] The cool-season turfgrass species is rye, where the effective dose of simazine is approximately 0.25 lb AI / A.

[0025] The cool-season turfgrass species is bentgrass, and the effective dose of simazine is approximately 0.05 lb AI / A.

[0026] In another aspect, a method for selectively controlling Paspalum vaginatum in a lawn containing Bermuda grass is disclosed. This method includes applying an effective dosage of simazine to the lawn.

[0027] The implementation may include one or more or all of the following.

[0028] The effective dosage of simazine is about 0.5 lb AI / A.

[0029] In yet another aspect, a composition containing simazine and a herbicide for removing ryegrass is disclosed. The amount of the herbicide for removing ryegrass may be the manufacturer's recommended amount for removing ryegrass.

[0030] The implementation may include one or more or all of the following.

[0031] The herbicide for removing ryegrass is pendoxulam, where the weight ratio of simazine to the herbicide for removing ryegrass is 1:1.

[0032] [[ID=?]]The foregoing and other aspects, features and advantages will become apparent from the specification, claims and drawings.

[0033] The patent or application file contains drawings executed in color. Copies of this patent or patent application publication with color drawings will be provided by the Office upon request and payment of the necessary fee.

Brief Description of the Drawings

[0034] [Figure 1] FIG. 1A is a photograph of a ryegrass lawn test area containing Digitaria sanguinalis 90 days after treatment. This area was further divided into four sections for four types of treatments. FIG. 1B shows a graph quantifying the distribution of ryegrass and Digitaria sanguinalis in the test area. It should be noted that there is an error in the original text at line 27. The correct English expression should be "The foregoing and other aspects, features and advantages will become apparent from the specification, claims and drawings." instead of what was originally there which is not grammatically correct English. I have translated it as best as possible based on the context. [Figure 2] Figures 2A and 2B are photographs showing the selective control of annual bluegrass in a test field with ryegrass turf, different from the location in Figure 1A. Simazine was applied in a single dose at a higher application rate of 1.0 lb AI / A to the test field in Figure 2A. Simazine was also applied in a single dose at a higher application rate of 0.75 lb AI / A to the test field in Figure 2A. [Figure 3] Figure 3A is a photograph of the ryegrass turf test area containing annual bluegrass 86 days after treatment. To compare the effectiveness of a single application of simazine in controlling annual bluegrass, this area was further divided into five sections with four different application rates. Figure 3B shows a graph quantifying the percentage of annual bluegrass in the test area 79 days after treatment. [Figure 4] Figure 4A is a photograph of a ryegrass turf test area containing annual bluegrass leucobryum (Poa annua) 83 days after treatment (on a different property as FIG. 3A). This area was further divided into four sections to compare the effectiveness of single or multiple applications of simazine at various application rates in controlling annual bluegrass leucobryum. Figure 4B shows a graph quantifying the percentage of annual bluegrass leucobryum in the test area 83 days after treatment. [Figure 5] Figure 5A is a photograph of a ryegrass turf test area containing annual bluegrass (Poa annua) 88 days after treatment (on a different property as FIG. 3A). This area was further divided into four sections to compare the effectiveness of single or multiple applications of simazine at various application rates in controlling annual bluegrass. Figure 5B shows a graph quantifying the percentage of annual bluegrass in the test area 85 days after treatment. [Figure 6]Figure 6A is a photograph of a ryegrass turf test area containing annual bluegrass leucobryum (Poa annua) 60 days after treatment (on a different property as FIG. 3A). This area was further divided into four sections to compare the effectiveness of various application rates of simazine in controlling annual bluegrass leucobryum with single, double, or triple applications. Figure 6B shows a graph quantifying the percentage of annual bluegrass leucobryum in the test area 60 days after treatment. [Figure 7] Figures 7A and 7B are photographs demonstrating that simazine effectively controls Poa annua on bentgrass (Agrostis sp.) golf course greens. [Figure 8] Figures 8A-8C are photographs that clearly show that a single application of simazine treatment resulted in a darker green color for the test turf, which is aesthetically desirable and represents a darker green color for the ryegrass. As shown in Figures 2A, 2B, and 3A, the treated ryegrass exhibits a darker green color than the ryegrass outside the treated area, especially in areas with higher application rates. [Figure 9] Figures 9A and 9B are photographs showing that applying sublethal doses of simazine multiple times suppresses the production of Poa annua flowers and seed heads, resulting in a more visually desirable turf. The test turf shown in Figures 9A and 9B is a ryegrass turf invaded with Poa annua, which was treated twice with simazine at a dose of 0.25 lb AI / A per application. [Figure 10] Figure 10 shows a photograph of a test turf in a high-altitude climate. Similar to test turfs located in hot climates such as Phoenix, AZ, application of a climate-specific effective dose of simazine to this test turf resulted in the prevention of annual bluegrass invasion and a darker green color compared to untreated turf. [Figure 11]Figures 11A and 11B are photographs demonstrating that simazine application is not harmful to desired cool-season turfgrasses when applied before planting seeds. Figure 11A shows a Bermuda grass turf that was treated with simazine four days before planting ryegrass, and is about to enter dormancy. Figure 11B shows the same test turf 43 days after sowing the ryegrass area, containing healthy young ryegrass. [Figure 12] Figure 12 is a photograph illustrating that the results of herbicide treatment are improved by co-administration of simazine with other herbicides. Herbicides A and B were applied at low doses to weaken existing ryegrass turf invaded with Poa annua. Poa annua is not susceptible to either A or B. As shown in the untreated section, Poa annua may proliferate during herbicide treatment 60 days after treatment, but co-administration with simazine prevents Poa annua invasion during herbicide treatment. [Figure 13] Figure 13 is a photograph illustrating that simazine can be used to selectively control barnyard grass in Bermuda grass lawns. A single application of simazine at a dose of 0.5 lb AI / A eradicated barnyard grass without damaging the Bermuda grass. [Modes for carrying out the invention]

[0035] Detailed aspects of this disclosure and the application are described below in the detailed description of the technology that follows. For illustrative purposes, many specific details are given to provide a thorough understanding of the various aspects of this disclosure. However, it will be understood by those skilled in the relevant art that the implementation of the technology disclosed herein may be carried out without these specific details. It should be noted that there are many different and alternative applications to the technology disclosed herein. The full scope of the technology disclosed herein is not limited to the examples described below.

[0036] Where necessary, detailed implementations of this disclosure are included herein. It should be understood that the disclosed implementations are merely examples of the various forms in which the invention may be implemented. Therefore, the specific details disclosed herein should not be construed as limitations, but merely as a basis for teaching those skilled in the art how to use the invention. The following specific examples will allow for a more detailed understanding of this disclosure. However, these are provided merely as guidelines and do not imply any limitations.

[0037] This disclosure may be more readily understood by referring to the following detailed description, which is interpreted in relation to the accompanying drawings and examples that form part of this disclosure. It should be understood that this disclosure is not limited to the specific materials, methods, applications, conditions, or parameters described and / or shown herein, and that the terms used herein are merely for the purpose of describing specific practices as examples and are not intended to limit the claimed invention.

[0038] In general, the terms and phrases in this specification and the claims are given to those skilled in the applicable art in their simple, ordinary, and customary meanings.

[0039] Nevertheless, in descriptions of practices using simazine, the following terms are used in accordance with the definitions and explanations presented below. Nevertheless, other terms, definitions, and explanations may also be found throughout this document.

[0040] As used herein, "simazine" is the term in its broadest sense and refers to the following compound having the molecular formula CH3CH2NH(C3N3Cl)NHCH2CH3 and the IUPAC name 6-chloro-2-N,4-N-diethyl-1,3,5-triazine-2,4-diamine: [ka]

[0041] Simazine was first marketed by Geigy in 1956. Simazine is marketed in 4L, 90DF, 4F, 90WDG, and 80W formulations. Simazine may also be known by the following trade names and aliases: CAS122-34-9, Gesatop, Princep, Simanex, Aquazine, Tafazine, Herbex, Radocon, Batazina, Herbazin, Symazine, Taphazine, Amizine, Bitemol, Gesapun, Herboxy, Printop, Radokor, Simadex, Zeapur, Herbazin 50 or Herbazin-50, Primatol S, Aktinit S, Hungazin DT, Gesaran, Premazine, Simazin, Simazine, Simazine 80W, Gesatop 50, Tafazine 50-W, Cekuzina-S, Primatel S, 1,3,5-triazine-2,4-diamine, 6-chloro-N,N'-diethyl-CAT (herbicide), Yrodazin, Azotop, Simatsin-neste, 6-chloro-N2,N4-diethyl-1,3,5-triazine-2,4-diamine, Herbatoxol S, triazine A 384, Geigy 27,692, 2-chloro-4,6-bis(ethylamino)-1,3,5-triazine, 6-chloro-N,N'-diethyl-1,3,5-triazine-2,4-diamine, 2,4-bis(ethylamino)-6-chloro-s-triazine, 2-chloro-4,6-bis(ethylamino)-s-triazine, Bitemol S 50, s-triazine, 2-chloro-4,6-bis(ethylamino)-Framed, A 2079, H 1803, W 6658, 2,4-bis(ethylamino)-6-chloro-1,3,5-triazine, G 27692, Bitemol S-50, 1-chloro-3,5-bis(ethylamino)-2,4,6-triazine, G-27692, SG0C34SMY3,6-chloro-2-N,4-N-diethyl-1,3,5-triazine-2,4-diamine, CHEBI:27496, NSC-25999, 6-chloro-N,N'-diethyl-[1,3,5]triazine-2,4-Diamine, NCGC00094524-01, Cekusima, Batazine FLO, Herbex (pesticide), Tafazine (VAN), Caswell No. 740, 1,3,5-Triazine-2,4-Diamine, 6-Chloro-N2,N4-Diethyl-6-Chloro-N(2),N(4)-Diethyl-1,3,5-Triazine-2,4-Diamine, CCRIS 1469, HSDB 1765, EINECS 204-535-2, NSC 25999, UNII-SG0C34SMY3, EPA Pesticide Chemical Code 080807, BRN 0010895, Cekuzinas, Permazine, Herboxydiene, Printrex, Simatox, Simazat, Cekusan Gesatop, AI3-51142, Simazin solution, Princep 4G, Princep 4L, Simazine 50, Aquazine 90WDG, Caliber 90, Gesatop-50, Princep 80W, Triazine A384, Sim-Trol 4L, Princep Caliber 90, 2,4-bis(aethylamino)-6-chlor-1,3,5-triazine [German], Spectrum_001809, SIMAZINE [HSDB], SIMAZINE [IARC], SpecPlus_000400, Enamine_005673, SIMAZINE [ISO], SIMAZINE [MI], Spectrum2_001879, Spectrum3_000820, Spectrum4_000660, Spectru m5_001950, 2,4-bis(aethylamino)-6-chlor-1,3,5-triazine, Oprea1_871264, SCHEMBL37774, 1-chloro-3,4,6-triazine, BSPBio_002319, KBioGR_001039, KBioSS_002302, Simazine, analytical standard, SPECTRUM330028, BIDD:ER0337, DivK1c_006496, SPBio_001758, s-triazine,6-Bis(ethylamino)-, CHEMBL1605837, DTXSID4021268, KBio1_001440, KBio2_002300, KBio2_004868, KBio2_007436, KBio3_001819, [6-Chloro-4-(ethylamino)(1,3,5-triazin-2-yl)]ethylamine, ZINC121575, HY-B2046, NSC25999, Simazine 100 μg / mL in acetone, Tox21_11 1291, Tox21_202378, Tox21_300748, CCG-39417, MFCD00023174, STK386441, 2-chloro-4,6-di(ethylamino)triazine, 2-chloro-4,6-bis(ethylamino)triazine, 4,6-bis(ethylamino)-2-chlorotriazine, AKOS003629500, Tox21_111291_1, KS-5070, Simazine 10μg / mL in acetonitrile, WLN:T6N CN ENJ BM2 DM2 FG, IDI1_007908, Simazine 100 μg / mL in acetonitrile, NCGC00094524-02, NCGC00094524-03, NCGC00094524-04, NCGC00094524-05, NCGC00094524-06, NCGC00094524-07, NCGC00094524-09, NCGC00254653-01, NCGC00259927-01, AC-12676, DB-041663, 6-chloro-N,N'-diethyl-2,4-diaminetriazine, CS-0014141, FT-0603326, I1146, s-triazine, 2,4-bis( Ethylamino)-6-chloro-Simazine, PESTANAL, 1-chloro-3,5-bisethylamino-2,4,6-triazine, 2,4-di(ethylamino)-6-chloro-1,3,5-triazine, 2-chloro-4,6-bis-ethylamino-1,3,5-triazine, H10514, chloro-4,6-bis(ethylamino)-s-triazine, Q416160, J-004790, 1,5-triazine-2,4-diamine, 6-chloro-N,N'-diethyl-, 2,4-diamine-6-chloro-N,N'-diethyl-1,3,5-triazine, BRD-K01416914-001-02-3, N,N'-Diethyl-6-chloro-[1,3,5]triazine-2,4-diamine, 6-chloro-N,N'-diethyl-1,3,5-triazine-2,4-diyldiamine, 6-chloro-N2,N4-diethyl-1,3,5-triazine-2,4-diamine.

[0042] As used herein, "penoxulam" is the term used in its broadest sense, and refers to the molecular formula C2-(2,2-difluoroethoxy)-N-(5,8-dimethoxy-[1,2,4]triazolo[1,5-c]pyrimidine-2-yl)-6-(trifluoromethyl)benzenesulfonamide, as defined in the IUPAC name. 16 H 14 This refers to compounds with the following chemical structure containing F5N5O5S: [ka]

[0043] Penocissrum may also be known by the trade name Sapphire.

[0044] As used herein, “annual bluegrass” is the term used in its broadest sense and refers to the weed species Poa annua. Therefore, the terms “annual bluegrass” and “Poa annua” are used interchangeably herein.

[0045] As used herein, “control” or “control” is the term in its broadest sense and may mean to completely kill a weed species at a lethal dose, to reduce the weed species’ competitive ability against a desired cool-season turfgrass species at a sublethal dose, or to alter the behavior of a weed species at a sublethal dose, all of which do not harm or cause unacceptable damage to the desired cool-season turfgrass species. With respect to Poa annua, the term to control may mean to eradicate Poa annua from a turfgrass crop, reduce the Poa annua population compared to a turfgrass crop, sublethally reduce Poa annua growth and / or completely or partially reduce Poa annua seedhead production.

[0046] As used herein, “suffering unacceptable damage” or “being unacceptably damaged” is the broadest term and may refer to any reduction in the ground cover (or soil cover) by the desired turfgrass or any visual impairment of the desired turfgrass (e.g., discoloration or fading of the lawn's color).

[0047] As used herein, “cool-season grass” is the broadest term and may refer to ryegrass, bentgrass, fescue, or other C-3 grasses cultivated as turfgrass.

[0048] As used herein, "AI / A" is the term used in its broadest sense and refers to active ingredient per acre or active ingredient per acre.

[0049] As used herein, “dosage” or “application rate” refers to the amount or weight of the active ingredient per acre, in its broadest sense. The application rate and frequency will vary depending on the turfgrass species and prevailing temperature.

[0050] As used herein, the terms “simultaneous administration” or “simultaneous administration” refer to the application of multiple treatments / herbicides in a single composition or in separate compositions, administered sequentially.

[0051] As used herein, “approximately” is a term used in its broadest sense in a numerical context, indicating an interval of accuracy that is well known to those skilled in the art and acceptable. This interval may be ±2% of a given value, preferably ±5% and most preferably ±10% of the numerical value, where applicable.

[0052] The singular forms "a," "an," and "the" refer to multiple objects unless otherwise explicitly indicated by the context. Therefore, for example, a reference to "stages" refers to one or more of these stages.

[0053] The terms “representative,” “example,” or any of their various forms are used herein to mean example, instance, or illustrative. No aspect described herein as “exemplary” or “example” should necessarily be construed as preferable or advantageous over any other aspect. Furthermore, examples are provided solely for clarity and understanding and do not in any way limit or restrict the subject matter disclosed in this disclosure or any relevant portion thereof. Numerous further or alternative examples that would vary the scope could be given but have been omitted for brevity.

[0054] When a range of values ​​is expressed, another implementation includes one specific value and / or another specific value. Similarly, when a value is expressed as an approximation, the preceding use of "approximately" will be understood to mean that a particular value forms another implementation. All ranges are inclusive and combinable.

[0055] Throughout this specification and in the claims, the terms “comprise” and “contain” and variations thereof, such as “to include” and “comprises,” mean “to include but not limited to,” and are not intended to exclude (and do not exclude) other components.

[0056] As used herein, the term "plural" means more than one.

[0057] The applicant has discovered a novel application of simazine and its related analog, atrazine, in turfgrass management. For the first time, simazine and atrazine are found to be useful for improving the quality and appearance of turfgrasses, including cool-season grasses.

[0058] One embodiment describes a method for controlling annual bluegrass (Poa annua) in turfgrasses including cool-season grass species, in which an effective dose of simazine or atrazine is administered to the turfgrass.

[0059] The most undesirable aspect of annual bluegrass (Poa annua) invasion of desired turfgrasses is its characteristic prolific production of flowers and seed heads. The white flowers can make the green lawn appear white. The prolific seed heads that follow flowering are also visually undesirable and interfere with the rolling of a ball on the surface. Another drawback of annual bluegrass invasion in lawns, including cool-season turfgrasses, is the relatively low tolerance of annual bluegrass to high temperatures. Therefore, the quality of the invaded lawn can deteriorate when the components of the annual bluegrass die back in midsummer.

[0060] Accordingly, another embodiment describes a method for reducing the formation of annual bluegrass flower and seed heads in turfgrasses including cool-season turfgrasses. Another embodiment describes a method for enhancing the color tone of turfgrasses including cool-season turfgrasses, in which an effective dose of simazine or atrazine is administered to the turfgrass.

[0061] The effective dose of simazine or atrazine is the amount of herbicide applied that does not cause unacceptable damage to the turf at the time of herbicide application. The effective dose may be lower when simazine or atrazine is used in multiple applications rather than a single application. Multiple applications use lower doses compared to a single application with a higher dose. In some implementations, each application of simazine or atrazine is spaced at least one week apart, for example, two to four weeks. Since the safety margin of atrazine is smaller for the desired cool-season turfgrass species, in preferred embodiments, the effective dose of simazine is applied to turfgrasses containing cool-season turfgrasses to prevent annual bluegrass invasion in the turfgrass, enhance the color tone of the turfgrasses containing cool-season turfgrasses, and / or reduce the formation of annual bluegrass flower and seed heads in the turfgrasses.

[0062] Another embodiment describes a method for enhancing the herbicidal effect of other herbicides. This method may include co-administering simazine with another herbicide to remove cool-season turfgrass species, such as ryegrass. The other herbicide may be penoxulam. Accordingly, a composition comprising simazine and an herbicide for killing cool-season turfgrass species is disclosed. In some embodiments, the herbicide kills ryegrass. Accordingly, in some embodiments, the composition comprises simazine and a ryegrass-removing herbicide, and the amount of ryegrass-removing herbicide in the composition is the manufacturer's recommended amount for removing ryegrass. In some embodiments, the ryegrass-removing herbicide is penoxulam, and the weight ratio of simazine to penoxulam is 1:1.

[0063] In another embodiment, a method for selectively controlling Paspalum vaginatum in Bermuda grass-containing turf is described, in which an effective dose of simazine is administered to the turf. The effective dose of simazine for controlling the invasion of Paspalum vaginatum in Bermuda grass-containing turf is the herbicide application rate at which the Bermuda grass-containing turf does not suffer unacceptable damage when the herbicide is applied, for example, 0.5 to 1.0 lb AI / A.

[0064] 1. Control of annual bluegrass in cool-season turfgrasses Poa annua is an undesirable inclusion in lawns. It has the following characteristics that make it undesirable: Poa annua has relatively low tolerance to high temperatures. Therefore, it tends to die in the summer, resulting in an undesirable state for the lawn.

[0065] Poa annua also produces prolific seed heads, which begin as aesthetically undesirable white flowers. Later, these seed heads produce visually undesirable seeds. Furthermore, these seeds deflect golf balls as they roll along the ground, thus reducing the quality of play on the green.

[0066] Furthermore, Poa annua, due to its considerable growth rate, tends to create bulges in the afternoon during cold weather when the growth of other grasses may be minimal. When encroaching on the desired grass species on the green, the afternoon bulges can distort the path of the golf ball as it rolls across the green.

[0067] Conversely, in hot weather, temperature-stressed Poa annua may proliferate minimally compared to the desirable mixed turfgrass. Again, the difference in height will distort the roll of the golf ball on the green.

[0068] The texture and thatch accumulation of Poa annua turf surface differ from that of desirable turfgrasses. Therefore, the encroachment of Poa annua on desirable turfgrasses results in surfaces that are inconsistent with playing performance objectives.

[0069] Poa annua has an aesthetically undesirable yellowish-green hue compared to other cool-season turfgrass species.

[0070] Both cool-season turfgrasses and Poa annua share similar growth patterns and metabolic characteristics, meaning there are only minor differences between them for selective control. Therefore, unlike warm-season turfgrasses, there are few commercially available herbicides for controlling Poa annua in cool-season turfgrasses. Those known and available are unreliable in terms of performance and control selectivity.

[0071] The applicant has surprisingly discovered that simazine can selectively control the weed annual bluegrass (Poa annua) without causing unacceptable damage to the desired cool-season turfgrass species. In other words, when the weed annual bluegrass invades a desired cool-season turfgrass species (ryegrass, bentgrass, fescue), simazine controls the annual bluegrass without damaging the desired species.

[0072] Selective control refers to simazine's ability to exert a harmful effect on a weed species without causing unacceptable damage to the desired turfgrass species. To achieve selectivity, different metabolic activities in response to temperature can be utilized. Annual bluegrass (Poa annua) is metabolically active and grows vigorously at low temperatures. During this period of high metabolic activity, it is susceptible to the herbicidal and controlling effects of simazine herbicides.

[0073] At these same low temperatures, the metabolic activity of the desired turfgrass species (ryegrass, bentgrass, fescue) is relatively low, and therefore less sensitive (more tolerant) to simazine treatment. Application of simazine to turfgrasses, including cool-season turfgrass species, at a rate of 0.05–1.0 lb AI / A results in selective control of annual bluegrass. Notably, this application rate can be applied to cool-season turfgrasses across a wide range of climates and elevations.

[0074] Desired cool-season turfgrass species have different tolerances to simazine application. Therefore, application rates and schemes differ among these species to adapt to variable tolerances without damaging the desired species.

[0075] For ryegrass lawns, the application rate to prevent annual bluegrass invasion is generally in the range of 0.1 to 1.0 lb AI / A. While both methods can effectively control annual bluegrass, applying smaller amounts multiple times may be safer for the ryegrass than applying a larger amount in a single application.

[0076] On the other hand, bentgrass turfgrass species are more sensitive to simazine application than ryegrass. Therefore, lower application rates are appropriate to reduce the likelihood of bentgrass damage. Appropriate application rates for controlling annual bluegrass in bentgrass turfgrass are generally in the range of 0.05–0.25 lb AI / A. Several simazine treatments per year may be necessary, and controlling annual bluegrass in bentgrass turfgrass is a longer-term program.

[0077] In some implementations, a single treatment plan involves multiple applications of simazine until an immediate annual bluegrass invasion is controlled. If another episode of annual bluegrass invasion occurs later, a second treatment plan may be initiated.

[0078] Those skilled in the art can determine the dosage of simazine for a particular cool-season turfgrass species in its growing environment and climate through routine experiments. For example, if annual bluegrass invasion appears to be poorly controlled, simazine may be applied to the turfgrass, including the cool-season turfgrass, multiple times, with each application spaced at least one week apart, so that the dose provided by each application is lower compared to a single application of simazine. In some implementations, each application in a treatment regime is spaced 2 to 4 weeks apart. In certain implementations, each application in a treatment regime is spaced 3 weeks apart.

[0079] Unless otherwise noted, the data and results presented herein are from trials conducted in Phoenix, AZ, and represent representative examples of the application of the methods described herein in hot climates. However, simazine is effective in controlling annual bluegrass invasion in turfgrasses, including cool-season turfgrass species, in cold, high-altitude climates as well as in hot climates (see Figure 10). This trial was conducted in accordance with the standards required by the U.S. Environmental Protection Agency for herbicide evaluation.

[0080] Figure 1A shows the ryegrass / annual bluegrass turf test areas subjected to four different treatments. The first treatment was carried out in December. Treatment area #1 was given a low dose of simazine (0.25 lb AI / A), followed by a second low dose one month later. Treatment area #2 received two moderate doses (0.5 lb AI / A) on the same schedule as treatment area #1. Treatment area #3 received a single moderate dose. Treatment area #4 received no simazine treatment. The test areas were evaluated 90 days after the initial treatment, as shown in Figure 1A, and quantitative data are given in Figure 1B. As is evident from Figure 1B, during the 90-day treatment period, when normal high temperatures were increasing, annual bluegrass began to overtake the turf (reducing the percentage of ryegrass without treatment).

[0081] Figure 2A illustrates the selective control of annual bluegrass in another experimental plot with a single application of simazine at a higher dose (1.0 lb AI / A) using a 4 L formulation. Figure 2B represents a single application at 0.75 lb AI / A using a 90 DF formulation. Therefore, the effective dose of simazine does not change based on the simazine formulation. Figure 3A compares single applications of 0.25 lb AI / A, 0.5 lb AI / A, 0.75 lb AI / A, and 1.0 lb AI / A 86 days after treatment. Figure 3B quantifies the percentage of annual bluegrass coverage on the test turf 79 days after treatment. Without any treatment, over 80% of the turf was covered with annual bluegrass (Poa annua), but a single application at the minimum dose (0.25 lb AI / A) reduced the annual bluegrass coverage to 50%. At the maximum dose (1.0 lb AI / A), annual bluegrass was effectively removed from the treated turf as visible.

[0082] Therefore, for safe and effective control of annual bluegrass invasion in ryegrass turfgrass, as exemplified above, application rates are generally in the range of 0.1–1.0 lb AI / A. Higher application rates result in more effective control than lower rates. However, although both can effectively control annual bluegrass, multiple applications at lower rates may be safer for ryegrass than a single application at a higher rate (Figures 4A–6B). Multiple applications of simazine at lower rates reduce the risk of over-administration to desirable cool-season grasses due to overlapping applications, which often occurs during turfgrass treatment. Although photographic records are not provided herein, multiple applications at a low rate of 0.05 lbs AI / A successfully controlled Poa annua in turfgrasses including cool-season grasses.

[0083] Bentgrass turfgrass species are more susceptible to simazine application than ryegrass. Therefore, lower application rates are appropriate to reduce the likelihood of bentgrass damage. Appropriate application rates for controlling annual bluegrass in bentgrass turfgrass may range from 0.05 to 0.5 lb AI / A. As shown in Figures 7A and 7B, simple application of simazine to turfgrass containing bentgrass at a rate of 0.5 lb AI / A effectively controlled annual bluegrass invasion. While annual bluegrass was still present in large numbers 13 days after treatment, the patches of annual bluegrass were visibly pathological (Figure 7A). By 38 days after simazine treatment, the coverage of the treated area in the test area with annual bluegrass was significantly reduced.

[0084] A method for reducing the flowering and seed head formation of annual bluegrass in turfgrasses, including cool-season turfgrass species, comprises applying an effective dose of simazine to the turfgrass. The effective dose is the sublethal dose of simazine for both cool-season turfgrasses and annual bluegrass in the turfgrass.

[0085] When annual bluegrass (Poa annua) is severely invaded a turfgrass, including cool-season grasses, it may not be desirable to apply simazine in doses that kill the bluegrass and thus leave exposed soil. However, applying sublethal doses of simazine to annual bluegrass also improves the quality of turfgrasses, including cool-season grasses. Using sublethal doses to annual bluegrass (at least in the short term), simazine treatment suppresses the production of annual bluegrass flowers and seed heads, thereby resulting in a more desirable turfgrass condition.

[0086] Plot #1 in Figure 8A was treated with simazine (0.25 lb AI / A). Only a portion of the annual bluegrass died, while flowering and seed head formation were suppressed in the surviving annual bluegrass plants (lime green area). The other areas were untreated, where the annual bluegrass produced prolific flowers and seed heads. Figures 9A and 9B show that multiple applications were made to a ryegrass turf invaded with Poa annua. This treatment did not kill the Poa annua; however, flower and seed head formation was significantly suppressed, thus improving the desirability of the turf.

[0087] Since annual bluegrass (Poa annua) is not susceptible to certain herbicides used to weaken existing ryegrass, treatment with such herbicides may not be beneficial for removing the turf once annual bluegrass has invaded the area. However, mixing simazine with the herbicide improves the outcome of herbicide treatment in turf removal. As shown in Figure 12, herbicides A and B were applied at low doses to weaken an existing ryegrass turf containing an annual bluegrass invasion. Annual bluegrass is not susceptible to either herbicide. Therefore, annual bluegrass was able to invade when the ryegrass was weakened. However, mixing either herbicide with simazine allowed the herbicide to achieve the desired result without allowing annual bluegrass to proliferate.

[0088] 2. Enhancement of the appearance and quality of turfgrasses, including cool-season grasses. Simazine can be used to enhance the color and quality of cool-season turfgrass species without relying entirely on controlling annual bluegrass invasion. This result is particularly desirable during periods of temperature stress.

[0089] As can be seen in Figures 2A and 2B, the treated ryegrass exhibits a darker green hue than the ryegrass outside the treated area. The same is illustrated in Figure 3A with higher simazine application rates. Figures 8B and 8C illustrate the darker green hue of the treated ryegrass compared to the untreated area.

[0090] Simazine can also be applied to turfgrasses, including cool-season grasses, in specialized situations. For example, when converting from ryegrass turfgrass oversown in spring to perennial Bermuda grass, a sublethal dose of sapphire herbicide (or other ryegrass-removing herbicide) is applied to allow the ryegrass to slowly disappear. However, ryegrass-removing herbicide treatment degrades the color and quality of the ryegrass during this process. Including a sublethal dose of simazine along with the sapphire treatment not only prevents the degradation of turfgrass quality but also enhances the color and quality of the ryegrass turfgrass throughout the entire process. In such embodiments, the sublethal dose of simazine has an application rate of approximately 0.25 AI / A. Bentgrass turfgrass color enhancement is achieved with comparatively much smaller amounts. In other embodiments, a method for enhancing the color and quality of turfgrasses, including cool-season grasses, involves the simultaneous application of simazine with penoxulam or other ryegrass-removing herbicides to turfgrasses containing cool-season grasses. In such implementations, the application of a sublethal dose of simazine associated with the desired cool-season turfgrass species is carried out simultaneously with herbicides used to remove penox slum or other ryegrass.

[0091] Simazine can also be applied during the transition of turfgrass from warm-season to cool-season varieties. When applied before sowing seeds, simazine is not harmful to the desired cool-season turfgrass. Figure 11A shows a Bermuda grass turf that was treated with simazine four days before planting ryegrass, and is about to enter dormancy. As shown in Figure 11B, 43 days after sowing with ryegrass, the entire treated area is covered with healthy young ryegrass. Thus, the simazine treatment did not affect the young ryegrass.

[0092] Accordingly, a composition comprising simazine and a ryegrass-removing herbicide is disclosed. The amount of ryegrass-removing herbicide is the manufacturer's recommended amount for removing ryegrass. In some embodiments, the weight ratio of simazine to ryegrass-removing herbicide in the composition is 1:1.

[0093] 3. Control of Barnyard Grass in Warm-Sea Grass It was also discovered that simazine can selectively control barnyard grass (Paspalum vaginatum) in turfgrasses containing Bermuda grass. This method involves applying an effective dose of simazine to the turfgrass.

[0094] Bermuda grass and Paspalum vaginatum are both warm-season grasses. However, when one species is desired, contamination of the other species is often observed. This is undesirable when Paspalum vaginatum is present in Bermuda grass. Since Bermuda grass is considerably more resistant to simazine than Paspalum vaginatum, it has been found that simazine can be used to selectively remove Paspalum vaginatum. Figure 13 illustrates the use of simazine (application rate 0.5 lb AI / A) to eradicate Paspalum vaginatum without damaging Bermuda grass.

[0095] Other implementations are conceived and possible. These implementations enumerated herein, as well as many other implementations, will be readily apparent from this disclosure. Further implementations are within the scope of the claims.

Claims

1. A method for using simazine to control annual bluegrass (Poa annua) in a turfgrass containing cool-season grass species, comprising applying an effective dose of simazine to the turfgrass, wherein the effective dose of simazine does not cause unacceptable damage to the cool-season grass species.

2. The method according to claim 1, wherein the effective dose of simazine suppresses the growth of annual bluegrass in turfgrasses including cool-season turfgrass species.

3. The method according to claim 1 or 2, wherein the cool-season turfgrass species includes at least one species selected from the group consisting of rye, bentgrass, and fescue.

4. The method according to any one of claims 1 to 3, wherein the effective dose of simazine is about 0.01 lb AI / A to about 1.0 lb AI / A.

5. The method according to claim 4, wherein the effective dose of simazine is approximately 0.5 lb AI / A to approximately 1.0 lb AI / A.

6. The method according to claim 5, wherein simazine is administered once.

7. The method according to claim 5, wherein simazine is administered twice, with each administration spaced approximately three weeks apart.

8. The method according to claim 5, wherein simazine is administered two or fewer times, with each administration spaced 1 to approximately 4 weeks apart.

9. The method according to claim 4, wherein the effective dose of simazine is about 0.01 lb AI / A to about 0.25 lb AI / A.

10. The method according to claim 9, wherein the effective dose of simazine is about 0.05 lb AI / A to about 0.25 lb AI / A.

11. The method according to any one of claims 2, 3, 9, and 10, wherein the effective dose of simazine is administered at least twice, with each administration spaced at least one week apart.

12. The method according to claim 11, wherein each application is spaced approximately one to four weeks apart.

13. The method according to claim 11, wherein each application is spaced approximately three weeks apart.

14. The method according to claim 9 or 10, wherein simazine is administered three times, with each administration spaced at least one week apart.

15. The method according to claim 14, wherein the cool-season grass species is rye, and the effective dose of simazine is about 0.1 lb AI / A to about 1.0 lb AI / A.

16. The method according to claim 14, wherein the cool-season grass species is bentgrass, and the effective dose of simazine is about 0.05 lb AI / A.

17. A method for reducing the formation of flowers and seed heads by Poa annua, comprising applying an effective dose of simazine to the Poa annua, wherein the effective dose of simazine is the sublethal dose of simazine for Poa annua.

18. The method according to claim 17, wherein the annual bluegrass grows in a turf containing a cool-season turfgrass species, and the effective dose of simazine is the sublethal dose of simazine for both the annual bluegrass and the cool-season turfgrass species.

19. The method according to claim 18, wherein the cool-season turfgrass species includes at least one species selected from the group consisting of rye, bentgrass, and fescue.

20. The method according to any one of claims 17 to 19, wherein the effective dose of simazine is about 0.25 lb AI / A.

21. A method for enhancing the color and quality of a turfgrass, including the aforementioned cool-season turfgrass species, comprising applying an effective dose of simazine to the turfgrass, wherein the effective dose of simazine is the sublethal dose of simazine for the aforementioned cool-season turfgrass species.

22. The method according to claim 21, wherein the cool-season grass species is selected from rye, bentgrass, or fescue.

23. The method according to claim 21 or 22, further comprising administering a herbicide simultaneously with the effective dose of simazine.

24. The method according to claim 23, wherein the herbicide is for killing cool-season grass species.

25. The method according to claim 23, wherein the herbicide is penoxulam.

26. The method according to any one of claims 21 to 25, wherein the effective dose of simazine is about 0.25 lb AI / A.

27. Shimazin and, Herbicides to remove ryegrass, A composition comprising the herbicide for removing ryegrass, wherein the amount of the herbicide for removing ryegrass is the manufacturer's recommended amount for removing ryegrass.

28. The composition according to claim 27, wherein the herbicide for removing ryegrass is penoxulam, and the weight ratio of simazine to the herbicide for removing ryegrass is 1:1.

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