To date, over 40,000 tree seedlings and nursery stock trees have been planted on over 90 acres of woodland habitat. The "Big Woods" habitat, which once dominated this region of Minnesota, has been diminished to only small remnants of what once existed. St. Olaf's restored woodland areas consist primarily of native hardwoods, recreating a small portion of the Big Woods habitat. Woodland plantings on the natural lands also include seven acres of coniferous forest, including tree species commonly found in Northern Minnesota. Although many of these conifers are not native to this region of Minnesota, we chose to establish some for educational purposes.
Most woodland restoration occurs on land recently coming out of agricultural production. In order to prevent soil erosion, perennial grasses are planted before any trees are planted. Between 400 and 500 tree seedlings are planted per acre within three years of grass seeding. As documented by student research projects, the seedling survival rate two years after planting has generally been between 60-80 percent. Since 2001, Direct Tree Seeding has been conducted on about 30 acres of St. Olaf land. Nuts and other seed forms are scattered at a rate of about 35,000/acre with a germination rate over 50 percent.
Habitat MaintenanceOne of the biggest factors related to maintaining restored habitats is weed control. This problem diminishes after the habitat becomes more established. Deer can also cause considerable damage to young trees by browsing on terminal buds. This problem is especially severe for white pine and red oak (see picture below).
Direct Tree Seeding
Old Main Tree Planting
Leif Knecht ('73)
Old Main Tree Plantings