Silvicultural Chemicals

May 24, 2011


Although no significant expansion in area of intensively managed forest in the United States is anticipated during the next 10-20 years, increased management intensity on selected company lands remains a key component of strategies for meeting demand for wood. Much of the world’s future incremental needs for industrial wood will likely come from plantations, which may require use of increasingly intensive practices, particularly repeated herbicide and fertilizer applications and reduced rotation lengths. Strengthening the body of technical information related to silvicultural chemicals and intensive management would enable member companies to more effectively meet economic goals while maintaining high environmental qualities.


Provide technical information that helps industry maintain access to silvicultural chemicals and intensive management systems to achieve wood production goals while meeting environmental expectations for industrial forest landscapes.

Examples of Recent or Ongoing Tasks 

  • Biodiversity Response to Intensive Management – This task is supporting three studies. A study in Mississippi is documenting response of habitat and bird, amphibian, reptile, small mammal, and arthropod communities in mid- and late-rotation loblolly pine plantations that have been subjected to vegetation control using herbicides, burning, and herbicides+burning. Two manipulative experiments (one in North Carolina and one in Mississippi) are evaluating habitat, bird, and small mammal response to varying intensities of management during stand establishment.
  • Texas Intensive Forestry Study – This study has been comparing water quality and hydrology in intermittent and ephemeral drainages resulting from current intensive management using current Best Management Practices with historical data gathered on these drainages in the 1970s and 1980s using minimal streamside management zones. A current phase of the project is testing how harvesting within the streamside management zone affects water quality.
  • Modeling Hydrology, Water Quality and Herbicides – This project is seeking to modify and test the APEX model (originally developed for agricultural landscapes) to improve predictions of flow, sediment losses, herbicides losses, and nutrient losses in forested ecosystems.
  • Effectiveness of SMZs in Minimizing Piedmont Stream Nutrient Fluxes Following Forest Fertilization – This study is assessing soil redox and surface and subsurface water flow and water quality in small catchments harvested in 2003-2004 and treated with diammonium phosphate and urea.
  • Georgia Herbicide Monitoring – NCASI staff analyzed water samples collected as part of the Dry Creek Study before and after applications of imazapyr and sulfometuron methyl. Results of these analyses were used to enhance the capacity of the APEX model to predict herbicide losses in forested ecosystems.
  • Literature Review of Toxicity to Fish and Wildlife of Herbicides and Adjuvants Used in Forest Vegetation Management Programs – NCASI staff are developing a series of Technical Bulletins synthesizing results of scientific studies of herbicide and adjuvant toxicity to fish and wildlife.
  • Technical Support on the Use of Silvicultural Chemicals in Forest Vegetation Management Programs – NCASI staff will monitor relevant scientific literature and activities of state and federal regulatory agencies and forest certification organizations, and will develop technical comments as appropriate.