Effects of single and multiple applications of glyphosate or aminopyralid on simple constructed plant communities. (29th August 2014)

• Record Type: Journal Article
• Authors: Pfleeger, Thomas; Blakeley‐Smith, Matthew; Lee, E. Henry; King, George; Plocher, Milton; Olszyk, David
• Is Part Of: Environmental toxicology and chemistry. Volume 33:Number 10(2014:Oct.)
• Page Start: 2368
• Page End: 2378
• Publication Date: 2014-08-29
• Subjects: Pollution -- Environmental aspects -- Periodicals; Environmental chemistry -- Periodicals; 615.902
• DOI: 10.1002/etc.2686
• Languages: English
• ISSNs: 0730-7268

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <sec id="etc2686-sec-0001" sec-type="section"> <p>To determine effects of multiple applications of herbicides on small constructed plant communities, <italic>Prunella vulgaris</italic> L.var. <italic>lanceolata</italic> Fern, <italic>Festuca roemeri</italic> (Pavlick) Alexeev, <italic>Clarkia amoena</italic> (Lehm.) Nels., and <italic>Cynosurus echinatus</italic> L. were grown together in small field plots. Plants were treated with glyphosate at target concentrations of 0 × , 0.01 × , 0.1 × , and 0.2× a field application rate (FAR) of 1122 g ha<sup>−1</sup> active ingredient (a.i.) for 3 yr in 1 location, and for 2 yr in a second location. Plants also were treated with aminopyralid at 0 × , 0.037 × , 0.136 × , and 0.5× FAR of 123 g ha<sup>−1</sup> a.i. for 2 yr in 2 locations. Plants received 1, 2, or 3 applications of each herbicide each year. Species and community responses depended on herbicide concentration and number of applications. With glyphosate, plant volume (modified formula for a cone) tended to decrease for all species (especially <italic>C. echinatus</italic>), and the decreases generally became larger with more applications. Plant communities exposed to the 2 greatest concentrations initially differed from controls but then appeared to recover. With aminopyralid, <italic>C. amoena</italic> was essentially eliminated from the communities, especially at the 2 greatest FARs, whereas the other 3 species tended to have significant increases in volume, especially at the 2 smallest FARs. With aminopyralid, increasing numbers of applications produced variable results, and the plant community volume never tended to recover. <italic>Environ Toxicol Chem</italic> 2014;33:2368–2378. Published 2014 Wiley Periodicals Inc., on behalf of SETAC. This article is a US Government work and, as such, is in the public domain in the United States of America.</p> </sec> </abstract>