Off-target herbicide deposition associated with treating individual trees

Environ Manage. 2005 Aug;36(2):237-47. doi: 10.1007/s00267-004-0080-3.

Abstract

There are a wide variety of different herbicide treatment methods used to remove single trees. Each method (cut-stump, basal, foliar) has a unique amount of off-target disturbance that should be considered in selecting a treatment for use in management. We quantified the amount of off-target deposition that resulted from four conventional herbicide application methods: 1) basal, 2) cut-stump, 3) high-volume, hydraulic foliar, and 4) low-volume, backpack foliar. Basal and cut-stump herbicide treatments deposited up to 200 and 4000 times more herbicide (a.i. per unit area) at groundline than the low-volume and high-volume foliar treatments, respectively. On a per tree basis, basal and cut-stump treatments deposited nearly six times more total herbicide than high-volume foliar, and 68 times more than low-volume foliar. All of the herbicide deposited off-target landed within 0.6 m of the basal and cut-stump treatments, 3.7 m with the low-volume foliar, and 7.3 m with high-volume foliar methods. Off-target herbicide deposition resulted in affected areas with killed or damaged vegetation ranging in size from 0.36 m2 (cut stump) to 7.08 m2 (high-volume foliar). Deposition amounts and affected areas were greater with larger trees, compared to smaller ones. We observed that 48% of the total amount of herbicide applied per plot was deposited off-target with cut-stump treatment, compared to only 4% to 11% for the other treatments. We suspect this difference is due to applicator error with the cut-stump treatment, likely related to the type of spray device used to apply the treatment.

Publication types

  • Comparative Study

MeSH terms

  • Environmental Monitoring / methods
  • Fluorescent Dyes
  • Glycine / analogs & derivatives
  • Glycine / analysis
  • Glycolates / analysis
  • Glyphosate
  • Herbicides / analysis*
  • Imidazoles / analysis
  • Niacin / analogs & derivatives
  • Niacin / analysis
  • Pesticide Residues / analysis*
  • Picloram / analysis
  • Rhodamines
  • Trees*

Substances

  • Fluorescent Dyes
  • Glycolates
  • Herbicides
  • Imidazoles
  • Pesticide Residues
  • Rhodamines
  • rhodamine WT
  • Niacin
  • 3,5,6-trichloro-2-pyridinyloxyactic acid 2-butoxyethyl ester
  • imazapyr
  • Picloram
  • Glycine