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Does Stem Injection of Glyphosate Control Invasive Knotweeds (Polygonum spp.)? A Comparison of Four Methods

Published online by Cambridge University Press:  20 January 2017

Erin N. Hagen
Affiliation:
College of Forest Resources, University of Washington, Box 352100, Seattle, WA 98195
Peter W. Dunwiddie*
Affiliation:
The Nature Conservancy, 1917 1st Ave., Seattle, WA 98101
*
Corresponding author's E-mail: [email protected]

Abstract

Japanese knotweed, Sakhalin knotweed, and their hybrid, Bohemian knotweed, are invasive across much of the United States. Monocultures formed by these species threaten natural riparian areas, and effective methods of control are being sought. Injection of herbicide is a relatively new control technique with no known published results. Bohemian knotweed was injected with four treatment dosages: 1 ml (0.03 oz) (0.48 g ae) (0.017 oz ae), 3 ml (0.10 oz) (1.44 g ae) (0.05 oz ae), or 5 ml (0.17 oz) (2.4 g ae) (0.08 oz ae) of undiluted glyphosate (suggested application), and 5 ml (0.17 oz) of a glyphosate : water mix (1 : 1, by vol) (1.2 g ae) (0.04 oz ae). Injections were tested at two heights on the plants: low node, 0.2 m (0.66 ft) (L) or chest height node, 1.0 to 1.3 m (3.3 to 4.3 ft) (M). After 1 mo, average percent injury was greater than 90%, and analysis showed no effect of injection location on the stem and no difference between the suggested 5-ml (0.17 oz) glyphosate application and 3-ml (0.10 oz) application. Nine months after treatment there was a reduction in knotweed height and density, though vigorous regrowth was evident within plots. Although the injection method results in the short-term dieback of injected stems, drawbacks to its use in certain scenarios should be considered when developing an integrated management plan for knotweed control.

Type
Research Articles
Copyright
Copyright © Weed Science Society of America 

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References

Literature Cited

Anderson, M. I. 2005. PERMANOVA: a FORTRAN computer program for permutational multivariate analysis of variance. Department of Statistics, University of Auckland, New Zealand.Google Scholar
Anonymous, , 2005. Aquamaster® herbicide product label. Monsanto Publication 21195E2-25. St Louis, MO Monsanto. 10.Google Scholar
Bímová, K., Mandak, B., and Kasparova, I. 2004. How does Reynoutria invasion fit the various theories of invasibility? J. Veg. Sci. 15:495504.CrossRefGoogle Scholar
Burgess, P. 2005a. Efficacy Trials – Injection Method Knotweed. http://www.clark.wa.gov/weed/documents/efficacy/knotweed%20files/155th%20Ave%20Knotweed%20Data.pdf. Accessed: December 15, 2006.Google Scholar
Burgess, P. 2005b. Efficacy Trials on Knotweed, Klineline, East Pond. http://www.clark.wa.gov/weed/documents/efficacy/knotweed%20files/klineline-canebkdown.pdf. Accessed: December 15, 2006.Google Scholar
Crockett, R. 2005. Controlling Knotweed Control Strategies and Recommendations 2005. http://www.monsanto.com/ito/pdfs/ControllingKnotweed.pdf. Accessed: December 19, 2006.Google Scholar
Dangles, O., Jonsson, M., and Malmqvist, B. 2002. The importance of detritovore species diversity for maintaining stream ecosystem functioning following the invasive of a riparian plant. Biol. Invasions 4:441446.Google Scholar
de Waal, L. C. 1995. Treatment of Fallopia japonica near water – a case study. Pages 203212. in Pysek, P., Prach, K., Rejmanek, M., Wade, M., eds. Plant Invasions – General Aspects and Special Problems. Amsterdam SPB Academic.Google Scholar
Forman, J. and Kesseli, R. V. 2003. Sexual reproduction in the invasive species Fallopia japonica (Polygonaceae). Am. J. Bot. 90:586592.Google Scholar
Geyer, F. 2004. Final Report for BIA Watershed Restoration Grant: Riparian Restoration in the Dickey Watershed of the Quillayute River System. http://www.clark.wa.gov/weed/documents/Dickey%20River%20Knotweed%20Report.pdf. Accessed: December 18, 2006.Google Scholar
Gozart, C. 2005. The 2004 East Fork Knotweed Control Project; Results Data, May 2005. http://www.jkinjectiontools.com/Research%20Docs/Lewis%20River%202004%20Results.doc. Accessed: January 22, 2007.Google Scholar
Holman, M., Dunwiddie, P., and Carey, B. 2007. Rapid spread of invasive knotweed in a riparian setting. Ecol. Res. 25:140141.Google Scholar
Miller, T. 2005. Evaluation of Knotweed Control Projects in Southwestern Washington. http://agr.wa.gov/PlantsInsects/Weeds/Knotweed/docs/Knotweed_Evaluation_SW_WA.pdf. Accessed: December 12, 2006.Google Scholar
Seiger, L. A. and Merchant, H. C. 1997. Mechanical control of Japanese knotweed (Fallopia japonica [Houtt.] Ronse Decraene): effects of cutting regimes on rhizomatous reserves. Nat. Areas J. 17:341345.Google Scholar
Soll, J., Kreuzer, D., Strauss, K., Dumont, J., Jeidy, L., Drass, M., Aldassy, C., and Nemens, D. 2007. Sandy River Riparian Habitat Protection Project Report 2006. http://tncweeds.ucdavis.edu/moredocs/polspp03.pdf. Accessed: January 29, 2007.Google Scholar
Urgenson, L. 2006. The Ecological Consequences of Knotweed Invasion into Riparian Forests. M.S. thesis. Seattle, WA University of Washington, College of Forest Resources. 75.Google Scholar
Zika, P. F. and Jacobson, A. L. 2003. An overlooked hybrid Japanese knotweed (Polygonum cuspidatum X sachalinense; Polygonaceae) in North America. Rhodora 105:143152.Google Scholar