Skip to page content
USDA Forest Service

Research & Development Treesearch

Treesearch Home
About Treesearch
Contact Us
Research & Development
Forest Products Lab
International Institute of Tropical Forestry
Pacific Northwest
Pacific Southwest
Rocky Mountain
Southern Research Station
Help - We Participate  Government Made Easy

Global Forest Information Service

US Forest Service
P.O. Box 96090
Washington, D.C.

(202) 205-8333

You are here: Home / Search / Publication Information
Bookmark and Share

Publication Information

View PDF (221 KB bytes)

Title: Picloram Movement in Soil Solution and Streamflow from a Coastal Plain Forest

Author: Michael, Jerry L.; Neary, D.G.; Wells, M.J.M.;

Date: 1989

Source: Jounral of Environmental Quality. 18(1): 89-95. 1989

Publication Series: Miscellaneous Publication

Description: Picloram (4-amino-3,5,6-trichloropicolinic acid) was aerially applied to P longleaf pine (Pinus palustris L.) site in the upper constnl plain of Alabama to control kudzu [Purraria lobota (Willd.) Ohwi]. Pellets (10% a.i.) were spread at the rate of 56 kg ha-1 on loamy sand Typic Knnhspludult soils. Movement of this herbicide was monitored with mineral soil samples, tension-cup lysimeters, flow- proportional streamilow samplers, and discrete samplers. Piclornm levels in the upper 15 cm of mineral soil peaked at 0.96 to 2.25 mg kg-1 25 d after application, depending on slope position, and declined to 0.13 to 0.29 mg kg-1 1 yr later. In soil solution, picloram was detected at P depth of 0.4 m between 26 and 273 d after application.Only 4 of IS lysimeters consistently contained detectable residues. Maximum picloram levels in soil solution were 130, 450, and 191 mg m-3 for ridge, midslope, and toe-slope positions, respectively. Downstream monitoring began 4 d after the herbicide application, and art initial concentration of 68 mg m-3 of picloram was detected. The maximum downstream concentration of 77 mg m-3 occurred 18 d after the application, immediately after the second storm event. Downstream levels dropped to <10 mg m-3 after 90 d and to <2 mg m-3 after 200 d. Following localized retreatment along the steam more than a year after the initial treatment, levels climbed again into the 20 to 30 mg m-3 range. Most of the initial off-site movement came from B perennial stream that had been inadvertently treated, but subsequently storm runoff was the largest contributor to stream contaminntioion. Picloram residues in this streeam were similar to those observed downstream, but they were higher (up to 241 mg m-3 and dropped faster to below 2 mg m-3 after D 150.

Publication Notes:

  • We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
  • This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
  • You may send email to to request a hard copy of this publication. (Please specify exactly which publication you are requesting and your mailing address.)



Michael, Jerry L.; Neary, D.G.; Wells, M.J.M. 1989. Picloram Movement in Soil Solution and Streamflow from a Coastal Plain Forest. Jounral of Environmental Quality. 18(1): 89-95. 1989


 [ Get Acrobat ]  Get the latest version of the Adobe Acrobat reader or Acrobat Reader for Windows with Search and Accessibility

USDA logo which links to the department's national site. Forest Service logo which links to the agency's national site.