The University of Winnipeg



Jack and Scot Pine (trees) found critically injured in a forest

The jack pine budworm is the most important defoliator pest of jack pine forests in Canada. Severe outbreaks of the jack pine budworm can cause significant mortality and top-kill in jack pine forests within the span of one to two years. This observation is a result of UWinnipeg’s Johanna R. M. Robson’s undergraduate student thesis, entitled Tree-ring response of jack pine and scots pine to budworm defoliation in central Canada that was published as a paper in the Forest Ecology and Management journal, a leading scientific journal. Her co-authors are France Conciatori, Jacques C. Tardif and Keith Knowles.

As a consequence of global climate changes, the increased occurrence of droughts is expected to increase the frequency and severity of jack pine budworm outbreaks throughout the Canadian prairies. In this study, the impact of jack pine budworm defoliation on radial growth was assessed on two host tree species: jack pine and scot pine.

UWinnipeg’s Dr. Jacques Tardif is a professor of Biology and Environmental Studies and Sciences, a member of the Centre for Forest Interdisciplinary Research (C-FIR) and Robson’s advisor.

“Johanna is a student that resembles me, she brings life to the lab,” said Tardif. “She is a hard worker and I am sure she will be successful as a graduate student.”

Robson’s field work and sample processing was completed with the help of UWinnipeg’s Dendroecology lab technicians, France Conciatori and Johanna Hallmann.  Nia Perron and Justin Waito (master/undergraduate) are students who  also assisted Robson in the Dendroecology lab.

Knowles, a former UWinnipeg ecology instructor, provided maps and knowledge of the budworm history in Manitoba who also assisted Robson in her research.

Robson graduated this past June with a four-year Bachelor of Science with Honours in Environmental studies and sciences within the Forest Ecology stream. She will be pursuing a Master’s Degree in Science in Bioscience, Technology and Public Policy at the UWinnipeg in fall 2015.

You can view the paper at Tree-ring response of jack pine and scots pine to budworm defoliation in central Canada

Forest Ecology and Management publishes scientific articles that link forest ecology with forest management, and that apply biological and ecological knowledge to the management and conservation of man-made and natural forests. The scope of the journal includes all forest ecosystems of the world.

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