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Imazapic Activity in a Semiarid Climate in Downy Brome (Bromus tectorum)–Infested Rangeland and CRP Sites

Published online by Cambridge University Press:  20 January 2017

Krista A. Ehlert ,
Richard E. Engel  and
Jane M. Mangold
Krista A. Ehlert*
Affiliation:
Department of Land Resources and Environmental Sciences, Montana State University, Bozeman, MT 59717
Richard E. Engel
Affiliation:
Department of Land Resources and Environmental Sciences, Montana State University, Bozeman, MT 59717
Jane M. Mangold
Affiliation:
Department of Land Resources and Environmental Sciences, Montana State University, Bozeman, MT 59717
*
Corresponding author's E-mail: krista.ehlert@msu.montana.edu.
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Abstract

Chemical control of downy brome has focused on imazapic; however, imazapic efficacy in semiarid climates is unpredictable, possibly because of variable residual soil activity. Our objective was to characterize imazapic activity over 9 mo in rangeland and a Conservation Reserve Program (CRP) site following its application in the fall as affected by rate (0, 80, 160, 240 g ai ha−1) and quantity of plant residue (reduced, ambient). Greenhouse bioassays were conducted over two seasons (2010 to 2011 and 2011 to 2012) using soil collected at multiple dates after imazapic application. Quantity of plant residue did not affect downy brome biomass or response to imazapic. Imazapic reduced downy brome biomass (P < 0.05) across all sampling dates in both seasons, and the response to rates was consistent up to 200 d post application. Imazapic activity over time conformed to a biphasic model with activity being consistent, or slightly improving, up to about 160 and 150 d post application, and then dropping rapidly to the final sampling event 287 and 272 d post application in rangeland and at CRP sites, respectively. These results indicate that fall imazapic applications in semiarid climates persist into the spring, thus providing control of both fall-emerging downy brome seedlings and seeds that overwinter and emerge the following spring.

El control químico de Bromus tectorum se ha enfocado en imazapic. Sin embargo, la eficacia de imazapic en climas semiáridos es impredecible, posiblemente por su variable actividad residual en el suelo. Nuestro objetivo fue caracterizar la actividad de imazapic a lo largo de 9 meses después de su aplicación en el otoño, la influencia de sitios bajo el Programa de Reservas para Conservación (CRP), el efecto de la dosis (0, 80, 160, 240 g ai ha−1) y la cantidad de residuos vegetales (ambiental, reducida). Se realizaron bioensayos de invernadero durante dos temporadas (2010 a 2011 y 2011 a 2012) usando suelo colectado en múltiples fechas después de la aplicación de imazapic. La cantidad de residuo vegetal no afectó la biomasa de B. tectorum o la respuesta a imazapic. Imazapic redujo la biomasa de B. tectorum (P < 0.05) en todas las fechas de muestreo en ambas temporadas, y la respuesta a las dosis fue consistente hasta 200 d después de la aplicación. La actividad de imazapic a lo largo del tiempo se ajustó a un modelo bifásico teniendo una actividad consistente o ligeramente mejorando, hasta cerca de 160 y 150 d después de la aplicación, y luego cayendo rápidamente en el evento final de muestreo a 287 y 272 d después de la aplicación en pastizales y en sitios CRP, respectivamente. Estos resultados indican que las aplicaciones de imazapic en el otoño en climas semiáridos persisten hasta la primavera, bridando así control de plántulas que emergen en el otoño de B. tectorum y semillas que sobreviven el invierno y emergen durante la siguiente primavera.

Keywords

Imazapicdowny brome, Bromus tectorum L. BROTEBioassaychemical weed controlplant residuePlateau®soil residual activity
Type
Research Article
Information
Weed Technology , Volume 29 , Issue 3 , September 2015 , pp. 472 - 479
Copyright
Copyright © Weed Science Society of America 

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References

Literature Cited

Aichele, TM, Penner, D (2005) Adsorption, desorption, and degradation of imidazolinone in soils. Weed Technol 19:154–159 CrossRefGoogle Scholar
Ball, DA, Yenish, JP, Alby, T III (2003) Effect of imazamox soil persistence on dryland rotational crops. Weed Technol 17:161–165 Google Scholar
Bradley, BA (2009) Regional analysis of the impacts of climate change on cheatgrass invasion shows potential risk and opportunity. Glob Change Biol 15:196–208 CrossRefGoogle Scholar
Bresnahan, GA, Koskinen, WC, Dexter, AG, Lueschen, WE (2000) Influence of soil pH—sorption interactions on imazethapyr carry-over. J Agric Food Chem 48:1929–1934 CrossRefGoogle ScholarPubMed
Cobucci, T, Prates, HT, Falcao, CLM, Rezende, MMV (1998) Effect of imazamox, fomesafen, and acifluorfen soil residue on rotational crops. Weed Sci 46:258–263 CrossRefGoogle Scholar
Colquhoun, J (2006) Herbicide Persistence and Carryover. Madison, WI: University of Wisconsin Extension A3819. 12 pGoogle Scholar
Davison, JC, Smith, EG (2007) Imazapic provides 2-year control of weedy annuals in a seeded Great Basin fuelbreak. Native Plants J 8:91–95 Google Scholar
Eberle, DO, Gerber, HR (1976) Comparitive studies of instrumental and bioassay methods for the analysis of herbicide residues. Arch Environ Contam Toxicol 4:101–118 Google Scholar
Elseroad, AC, Rudd, NT (2011) Can imazapic increase native species abundance in cheatgrass (Bromus tectorum) invaded native plant communities? Rangel Ecol Manag 64:641–648 CrossRefGoogle Scholar
Kyser, GB, DiTomaso, JM, Doran, MP, Orloff, SB, Wilson, RG, Lancaster, DL, Lile, DF, Porath, ML (2007) Control of medusahead (Taeniatherum caput-medusae) and other annual grasses with imazapic. Weed Technol 21:66–85 Google Scholar
Littell, RC, Milliken, GA, Stroup, WW, Wolfinger, RD, Schabenberger, O (2006) SAS for Mixed Models. 2nd edn. Cary, NC: SAS Institute. 840 pGoogle Scholar
Mangels, G (1991) Behavior of the imidazolinone herbicides in soil—a review of the literature. Pages 191–209 in Shaner, DL, O'Conner, SL, eds. The Imidazolinone Herbicides. Boca Raton, FL: CRC Google Scholar
Mangold, J, Parkinson, H, Duncan, C, Rice, P, Davis, E, Menalled, F (2013) Downy brome (Bromus tectorum L.) control with imazapic on Montana rangeland. Invasive Plant Sci Manag 6:554–558 CrossRefGoogle Scholar
Mendenhall, W, Sincich, T (2011) Special topics in regression. Pages 466–471 in A Second Course in Statistics: Regression Analysis. 7th edn. Upper Saddle River, NJ: Prentice Hall Google Scholar
Monaco, TA, Osmond, TM, Dewey, SA (2005) Medusahead control with fall- and spring-applied herbicides on northern Utah foothills. Weed Technol 19:653–658 Google Scholar
Morris, C, Monaco, T, Rigby, CW (2009) Variable impacts of imazapic rate on downy brome (Bromus tectorum) and seeded species in two rangeland communities. Invasive Plant Sci Manag 2:110–119 Google Scholar
Moyer, JR, Esau, R (1996) Imidazolinone herbicide effects on following rotational crops in southern Alberta. Weed Technol 10:100–106 CrossRefGoogle Scholar
Onofri, A (1996) Biological activity, field persistence and safe recropping intervals for imazethapyr and rimsulfuron on a silty-clay soil. Weed Res 36:73–83 CrossRefGoogle Scholar
Owen, SM, Sieg, CH, Gehring, CA (2011) Rehabilitating downy brome (Bromus tectorum)—invaded shrublands using imazapic and seeding with native shrubs. Invasive Plant Sci Manag 4:223–233 CrossRefGoogle Scholar
Prostko, EP, Grey, TL, Morgan, RN, Davis, JW (2005) Oat (Avena sativa) response to imazapic residues. Weed Technol 19:875–878 Google Scholar
Ranft, RD, Seefeldt, SS, Xhang, M, Barnes, DL (2010) Development of a soil bioassay for triclopyr residues and comparison with a laboratory extraction. Weed Technol 24:538–543 CrossRefGoogle Scholar
Rice, PM (2005) Downy brome, Bromus tectorum L. Pages 147–170 in Duncan, CA, Clark, JK, eds. Invasive Plants of Range and Wildlands and Their Environmental, Economic, and Societal Impacts. Lawrence, KS: Weed Science Society of America Google Scholar
Sheley, L, Carpinelli, F, Sheley, RL, Carpinelli, MF, Morghan, KJR (2007) Effects of imazapic on target and nontarget vegetation during revegetation. Weed Technol 21:1071–1081 Google Scholar
Streibig, JC (1988) Herbicide bioassay. Weed Res 28:479–484 CrossRefGoogle Scholar
Tu, M, Hurd, C, Randall, JM (2001) Weed Control Methods Handbook: Tools and Techniques for Use in Natural Areas. The Nature Conservancy. https://www.invasive.org/gist/handbook.html. Accessed April 2, 2015Google Scholar
Ulbrich, AV, Souza, JRP, Shaner, D (2005) Persistence and carryover effect of imazapic and imazapyr in Brazilian cropping systems. Weed Technol 19:986–991 Google Scholar
Young, JA, Evans, RA (1975) Germinability of seed reserves in a big sagebrush community. Weed Sci 23:358–364 Google Scholar