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Forest management practices vary considerably across forest types, site conditions, market availability, and many other factors. There simply is not any single way or best way to manage all forests, or even a particular kind of forest. While nature is a dynamic system that defies simple categorization, there remains a body of knowledge and experience that can be very effectively applied.

Jack pine is one of our more common northern forest types, especially on sandy, well-drained soils. It's also one of our more interesting types, especially because of its adaptation to wildfire. Like many Lake States forest types, jack pine regeneration requires full sunlight to grow. This is true throughout the life of jack pine. Even moderate shade will significantly reduce tree vigor, adding to stress and increasing vulnerability to insects and diseases.

Historically, wildfires were the primary agent of jack pine reproduction. A major jack pine conflagration is an awesome sight to behold, and frightening. As stands would burn, the heat would cause sealed cones to open up over the subsequent few days. The seed would fall on mineral soil, laid mostly bare by the fire. These are the ideal conditions to secure jack pine regeneration. With full sunlight, jack pine grows very rapidly.

Today, forest managers work to prevent jack pine fires, which tend to run hot and fast. They are usually very difficult to control. However, most jack pine cones still need heat in order to release the protected seeds. Forest management uses clearcutting to create the needed environmental conditions.

Summer temperatures within a few inches of the sandy soils get high enough to cause jack pine cones to open. So, following a clearcut, leftover tops, called slash, are chopped to get the cones close to the ground. In this way, most jack pine stands regenerate naturally. When this sort of technique fails, a landowner can resort to planting.

Not all jack pine cones are "glued" shut. In mature trees, about 25 percent may open without the aid of high temperatures. In younger trees, this percentage is higher. Not all jack pine stands burned regularly, so the species employed a back-up strategy where some cones open without heat. Jack pine also produces cones at a young age, just in case that fire returned sooner than the average.

Jack pine budworm is another neatly fitting piece of jack pine ecology. When trees reach ages around 50 years, budworm populations begin to build. Given the right conditions, populations will reach epidemic proportions and will eventually feed even on the younger trees. Large portions of stands can be killed. The dead and dying timber create a very flammable situation. Of course, this feeds right into the regeneration strategy of the species.

Insect epidemics and wildfire do not fit well with human habitation. Natural is not always desirable. People who live in or near jack pine forests should be aware of the natural hazards. Dead trees should be removed. The forest should be set-back at least 100 feet from any structures. The "Firewise" program has suggestions to help reduce the risk of fire damage to homes.

Using clearcutting to create a patchwork of age classes across a jack pine landscape is a good strategy to minimize the risk of fire and insect outbreaks. Even if a fire does happen, when it reaches younger trees, then firefighters have a chance to control the fire. In larger timber, if crowns begin to burn, there is little that humans can do except get out of the way.

The mix of age classes is also the recovery strategy for one of the finest success stories of bringing an endangered species back from the brink of extinction. The Kirtland's warbler breeds in Michigan jack pine, and has fairly exacting requirements. The bulk of the Kirtland warbler management has been in the northern Lower Peninsula. Warbler populations have reached their recovery goals and breeding pairs have recently been sighted in Upper Peninsula jack pine stands.

Jack pine is an excellent example of where forest management has helped maintain a valuable forest type, reduced risks to people, and has played a critical wildlife recovery role. Jack pine timber is valued in making high quality paper, oriented-strand board, and new technologies that produce dimensional lumber. Together, these benefits serve to illustrate the advantages of managing a renewable and sustainable natural resource. Forest management, in many ways, is a key to our future.

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Bill Cook is an MSU Extension forester providing educational programming for the entire Upper Peninsula. His office is located at the MSU Upper Peninsula Tree Improvement Center near Escanaba. The Center is the headquarters for three MSU Forestry properties in the U.P., with a combined area of about 8,000 acres. He can be reached at cookwi@msu.edu or 906-786-1575.

Prepared by Bill Cook, Forester/Biologist, Michigan State University Extension, 6005 J Road, Escanaba, MI 49829
906-786-1575 (voice), 906-786-9370 (fax), e-mail: cookwi@msu.edu

Use / reprinting of these articles is encouraged. Please notify Bill Cook.
By-line should read "Bill Cook, MSU Extension" Please use the article trailer whenever possible.

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This website is maintained by Bill Cook, Michigan State University Extension Forest in the Upper Peninsula. Comments, questions, and suggestions are gratefully accepted.
Last update of this page was 5 November, 2018