Log Fumigation Update

2017 Forest Growers Conference
Report No:
Report Date:
October 18, 2017
Don Hammond: STIMBR

Log fumigation: update on research into alternatives to methyl bromide

Conference presenter: Don Hammond, STIMBR

Presentation:           Log Fumigation Update

Log exports continue to rise, and the environmental impacts of methyl bromide (MBr) are becoming increasingly unacceptable. From 2020, new EPA legislation requires that MBr must be recaptured after use.

Work continues to find alternatives to MBr which will meet the different phytosanitary requirements of New Zealand’s various overseas log markets. The outcomes sought by the research team are:

  • Continued ability to trade
  • Supported by science
  • Socially responsible/acceptable
  • Practical at scale

Progress to date

A comprehensive literature review and other work have led to the conclusion that there is no ‘one size fits all’ solution for the log export industry. Possible alternatives include:

  • EDN – the only potential alternative fumigant to MBr (phospine is only accepted by China). EDN is a ‘drop-in’ replacement for MBr, registration is underway, but there is still work to be done on its efficacy and acceptability, especially by China.
  • Risk free periods – a 4-year research programme focusing on an ecological approach – understanding risk by understanding insect behaviour – is in its early days.
  • Joule heating – work by the Electrical Engineering Department at the University of Canterbury has proved the effectiveness of joule heating in killing pests: challenges include upscaling the technique and its potential costs.
  • Debarking – a risk reduction technique rather than a phytosanitary one, and only accepted by China. The problem of waste disposal is significant.
  • Adjusting the use of MBr – research has shown that lower application rates may be possible. Various systems to recapture the gas after fumigation have been assessed, but globally MBr recapture has yet to be achieved at scale.

In summary – MBr continues to be an essential treatment for log exports to many countries. It is difficult to destroy or recapture, so alternatives are needed. The most promising fumigant is a chemical – EDN. Joule heating is also considered to have potential.

The industry needs time to address this challenge, and needs support, including from trading partners.

23 Log Fumigation Update_D Hammond (467.50 Kb)