Jack pine forests are ecologically and economically critical in the upper Great Lakes region and regeneration of these forests has been increasingly challenging in range margin populations due to drought, land conversion to agriculture, and other stressors.
For this reason, John Almendinger, a seasoned member of the Minnesota Department of Natural Resources (MN DNR), is grateful for NE CSC Graduate Fellow Kyle Gill’s recent research on jack pine forest dynamics.
For years, Almendinger and his colleagues have worked to decipher the complex dynamics of jack pine forests of Minnesota, with hopes of guiding the state towards silvicultural practices designed around their natural dynamics. Such information can be gained by studying natural dynamics using historical data and ecological methods in order to project future dynamics. Although northeastern Minnesota’s jack pine forests respond well to even-aged forest management, recent failures in regenerating central jack pine forests suggest that a different management approach is needed. “Each forest is different,” says Almendinger, “and the central jack pine forests are located on land that was prairie and didn’t become forested until about 1,000 years ago.” Jack pine is a species that is favored when soil nutrients are scarce, so Almendinger predicted that pine regeneration would be slower than desired by traditional management standards but that the volume of wood in these rich forests should catch up by the time they are harvested.
Yet, without scientific backing, implementing these theorized changes would be very difficult given the general lack of experience with managing these systems outside of traditional management regimes. These obstacles have made correction efforts seem like “turning the Titanic with a canoe paddle” for Almendinger. He teamed up with University of Minnesota Associate Professor and NE CSC Principal Investigator Tony D’Amato, and his graduate student Kyle Gill, to test the ideas. Ultimately, they hoped that viewing historical dynamics of several natural jack pine stands would lead to greater scientific insight and a chance to alter management strategies.
Kyle, with his extensive knowledge in dendrochronology, was the perfect candidate for the problem. Dendrochronology is the process of analyzing patterns in tree rings to determine the history of tree growth and forest dynamics. Dendrochronological samples are harmlessly taken from each tree throughout the study sites using an increment borer, which is a straw-sized equivalent of an ice corer. For Kyle, samples are the storybook of the tree’s life. Each tree’s sample is sanded down to clarify the boundary between rings, allowing Kyle to measure each ring and run statistical analyses on the variation in growth from one year to the next in order to read into the tree’s past. Kyle’s data displayed a wide range of tree establishment dates and growth patterns. This suggests central Minnesota’s Jack pine do not always fit the norm of the species and should be managed with a wider variety of silvicultural systems. These findings supported Almendinger’s hypotheses, a conclusion Almendinger said was both pleasing and humbling. “Our regeneration standards should change based on what Kyle [found],” states Almendinger, noting that the research has proven that the central jack pine forests do not fit into an industrial forest management model.
There are important functions to be played by scientific evidence in the process of designing management practices; evidence can break through resistant barriers by supplying educated hypotheses to ensure the effectiveness of future action. “We have field trials running based on what Kyle has found, but it takes a long time to show if things work in forestry…[Jack pines] do eventually regenerate… on their own [if given the time]” ensures an optimistic Almendinger. Armed with Kyle’s scientific evidence, Almendinger will confidently focus on natural models of forest management to ensure the sustainability of Minnesota’s jack pine forests. Almendinger believes this kind of research is critical in maintaining forest certifications, which in Minnesota is provided by both the Sustainable Forestry Initiative (SFI) and Forest Stewardship Council (FSC). For his part, Kyle is honored by the experience and thinks it an ideal fit for his passion to enhance forest management for long-term resilience and sustainability, “The Minnesota DNR and other agencies are required to rely on the best science available in order to maintain their sustainable forestry certifications and it is very exciting to think that our work is helping to set those standards. Working directly with stakeholders like the Minnesota DNR from the beginning of the research project is the best way to make such relevant contributions because they usually know what questions are applicable to their management decisions.”
By Colton Ellison, NE CSC Communications Intern, UMass Amherst
A range-margin jack pine (Pinus banksiana) forest/woodland. Stands like these are being sampled for a better understanding of their natural range of variability in order to update local management guidelines and more accurately model potential range-shifts in warming climate scenarios. (Photo: Gill)
Top photo: Kyle Gill collects Jack Pine samples for dendrochronology analysis.