INVASIVE WEED MANAGEMENT WITH AMINOPYRALID

Transcription

1 INVASIVE WEED MANAGEMENT WITH AMINOPYRALID Byron B. Sleugh*, Mary B. Halstvedt, Daniel C. Cummings, Pat L. Burch, William N. Kline, Vernon B. Langston, David Hillger, and Vanelle F. Peterson

2 Background Dow AgroSciences has a number existing active ingredients that provide control of many invasive plant species Aminopyralid is an innovative selective broadleaf herbicide designed and developed for the management of noxious and invasive weeds Not a Federally Restricted Use Pesticide Effective at rates from 52 to 120 g ae ha -1 (equivalent to 3-7 fl oz of Milestone) No injury to cool- or warm-season grasses Available as Milestone, Milestone VM, Milestone VM Plus, Chaparral, Opensight and ForeFront R&P herbicides Trademark of Dow AgroSciences LLC. Always read and follow label directions.

3 Reduced Risk Pesticide Program Aminopyralid was accepted for evaluation under U.S. EPA's Reduced Risk Pesticide program in October 2004 Acceptance for evaluation was based, in part, on: Improved control of invasive plants compared to market standards Lower rates than most market standards Data and risk assessment studies for toxicological, eco-toxicological and environmental fate

4 What is Reduced Risk? A reduced risk pesticide use is defined as one which "may reasonably be expected to accomplish one or more of the following": reduces pesticide risks to human health reduces pesticide risks to non-target organisms reduces the potential for contamination of valued, environmental resources broadens adoption of IPM or makes it more effective

5 Background Even with existing weed laws, noxious and invasive weeds continue to spread and cause significant economic and ecological damage Pastures, rangeland, and wildlife habitats, natural area sites often receive less than optimum management and can be a haven for invasive species Not many alternatives for control that could be used in certain areas e.g. up to water s edge, seasonally dry wet lands etc.

6 Aminopyralid reduces the environmental load of natural areas, rangeland/pasture and rights-of-way herbicides Weed Species Musk Thistle Canada Thistle Tropical Soda Apple Spotted & Diffuse Knapweed Yellow Starthistle Russian Knapweed Aminopyralid Dicamba 2,4-D Clopyralid Metsulfuronmethyl Picloram Triclopyr Application Rate of Aminopyralid (lb ae/a) Equals 1X for Each Key Species 1X (0.035) 8.9X 28.6X 4.5X 0.3X 4.5X 1X (0.09) 16.7X 16.7X 4.9X Not effective 4.9X 1X (0.1) Not effective Not Not effective Not effective Not effective labeled in FL 1X (0.085) 11.8X 11.8X 3.7X Not effective 3.7X 1X (0.065) 1X (0.08) Not effective Not effective 15.4X 3.3X Not effective 4.8X Not effective 5.5X Not effective 5.5X Not effective Not effective 10.0X No residual control Not effective Not effective Not effective

7 Key Weeds Controlled by Aminopyralid Weed species Application timing Common name Scientific name cinquefoil, sulfur Potentilla recta Prebud daisy, oxeye Chrysanthemum leucanthemum Prebud hawkweed, orange Hieracium aurantiacum Bolting hawkweed, yellow Hieracium pratense Bolting knapweed, diffuse Centaurea diffusa Bolting knapweed, spotted Centaurea maculosa Bolting Kudzu Pueraria lobata Foliar starthistle, yellow Centaurea solstitialis Rosette Teasel Dipsacus sativus Rosette-bolt thistle, Canada Cirsium arvense Prebud to early flower or fall thistle, musk Carduus nutans Rosette, bolting or fall thistle, plumeless Carduus acanthoides Rosette, bolting or fall Vetch Vicia spp. Preflower Wild parsnip Pastinaca sativa Rosette, bolting

8

9 Material and Methods Randomized complete block, 3-4 replications 0.25% Non ionic surfactant added to all treatments unless otherwise noted Multiple treatments based on species Rates and timing vary Each will be described separately Some data pooled over years

10 Seedling control (%) 100 Musk thistle (Carduus nutans) Autumn Application (October 26, 2002) a a a a a a a a 34 WAT Milestone VM Tordon 22K Dicamba (Banvel) Herbicide rate (fl oz/a) Milestone and Tordon are trademarks of Dow AgroSciences LLC. Tordon 22K is a Federally Restricted Use Pesticide. b

11 Density (no./m 2 ) Musk thistle fall application (October 26, 2002) b b b Milestone VM Tordon 22K Banvel Herbicide rate (fl oz/a) b a 34 WAT Milestone and Tordon are trademarks of Dow AgroSciences LLC. Tordon 22K is a Federally Restricted Use Pesticide.

12 Late bolt stage musk thistle (Carduus nutans) control DAA in Missouri and Nebraska Control Regrowth 0 Opensight1 oz Opensight1.5oz Opensight 2oz Cim 0.17oz Cim 0.24oz Cim 0.31oz Milestone VM 3 fl oz Cim Max R1 Trademark Dow AgroSciences LLC. Always read and follow label directions

13 Opensight TM 1oz product/acre 5 WAT Trademark Dow AgroSciences LLC. Always read and follow label directions

14 % Control Poison Hemlock (Conium maculatum) opensight 2 oz Opensight 2.5 oz Opensight 3.3 oz Mil VM Plus 1 gal Milestone VM 7 fl oz Journey 27 fl oz Missouri-110 DAA Applied April 29 th to 24 inch plants Trademark Dow AgroSciences LLC. Always read and follow label directions

15 Percent control Canada thistle (Cirsium arvense) Control with Fall Applications a ab ab ab b c Milestone VM Tordon 22K Transline Dicamba Herbicide rate (fl oz/a) (Banvel) Average of 5 sites North Dakota (2), Nebraska, Virginia, and Washington Milestone, Tordon and Transline are trademarks of Dow AgroSciences LLC. Tordon 22K is a Federally Restricted Use Pesticide.

16 Key Question from Land Managers Current Label: Apply Milestone VM at 5 to 7 fl oz per acre to plants in the prebud to early bud state..applications are also effective in the fall before a killing frost. Can aminopyralid still provide excellent control when applied in a wider application window?

17 Materials and Methods Locations and application dates : Fargo, ND Sept. 19, Oct. 1, Oct. 29 Eckleston, ND - Sept. 14, Oct. 1, Oct. 29 Scotts Bluff, NE Sept. 13, Oct. 16, Nov. 12

18 % Visual control Herbicide efficacy on Canada thistle at different application timings - Nebraska a a a a Sept. 13 Oct. 16 Nov. 12 Herbicide application date a a Milestone and Tordon are trademarks of Dow AgroSciences LLC. Tordon 22K is a Federally Restricted Use Pesticide. b a b b Milestone VM 5 fl oz Milestone VM 7 fl oz Tordon 22K 1.5 pts

19 % Visual control Herbicide efficacy on Canada thistle at different application timings- North Dakota a a a Sept. 14 & 19 a a a a a Oct. 1 Oct. 29 b Milestone VM 5 fl oz Milestone VM 7 fl oz Tordon pts Herbicide application date Milestone and Tordon are trademarks of Dow AgroSciences LLC. Tordon 22K is a Federally Restricted Use Pesticide.

20 Extending spring/summer application window Milestone VM at 5 and 7 fl oz/a at 4 timings Milestone is a registered Trademark of Dow AgroSciences LLC.

21 MN- June 25 SD-May 28th MN- July 9 SD- July 1 30 % Bud Full Flower Fuzz MN-July 23 SD- July 17th Dormant MN - August 25th SD August 17th

22 % Canada Thistle Control Canada Thistle Control at 4 Summer Timings MBH0703, MBH0816 Mean v alues below box, number of obs. abov e box * * 30 % Bud Full Flower Fuzz Dormant A: Milestone 5 fl oz/a A: Milestone 7 fl oz/a B: Milestone 5 fl oz/a B: Milestone 7 fl oz/a C: Milestone 5 fl oz/a C: Milestone 7 fl oz/a D: Milestone 5 fl oz/a D: Milestone 7 fl oz/a Milestone is a registered Trademark of Dow AgroSciences LLC

23 Conclusion for timing studies Milestone VM at 5 and 7 fl oz/acre in the autumn provided excellent control of Canada thistle Milestone VM provide better efficacy when applied later into the season than picloram. Even though Canada thistle leaves were beginning to senesce, there was still excellent efficacy by all herbicide applications up to late October as long as there was some green foliage. Milestone VM at 5 and 7 fl oz/acre provided excellent control at later growth stages (early flower) in the spring than currently recommended on the label Milestone and Tordon are trademarks of Dow AgroSciences LLC. Tordon 22K is a Federally Restricted Use Pesticide.

24 % control Common teasel (Dipsacus sativus) Milestone VM 5 fl oz Milestone VM + Garlon 3A (5+32 fl oz) Milestone VM+Garlon 3A (7+32 fl oz) Milestone VM 4.5 fl oz Telar+2,4-D (0.25 oz pr+32 fl oz) Avg. of 3 trials across 2 states. Milestone and Garlon are registered Trademarks of Dow AgroSciences LLC.

25 % Control Spotted knapweed (Centaurea maculosa) Rosette/bolting growth stage application YAT 2 YAT Milestone VM (fl oz/a) Tordon 22K (pt/a) Evaluations averaged over 5 locations Milestone Milestone and Tordon and Tordon are trademarks are trademarks of Dow of AgroSciences Dow AgroSciences LLC. LLC. Tordon Tordon 22K is 22K a Federally is a Federally Restricted Restricted Use Pesticide. Use Pesticide.

26 Spotted Knapweed Control WI Milestone VM herbicide applied at 5 fluid oz/acre - 3 yrs after treatment Milestone is a registered Trademark of Dow AgroSciences LLC.

27 Summary and Conclusions Aminopyralid and aminopyralid-containing mixtures provide excellent control of key noxious and invasive species. Aminopyralid can be applied over longer period of time to control Canada thistle compared to previous standards. Aminopyralid possesses the efficacy and key toxicological and environmental fate attributes that make it an excellent fit in invasive weed management programs.

28 Thank you. Questions?