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Upahke Pond on the Sager Tract.
Cofrin Center for Biodiversity

Natural and Planted Features

The Cofrin Memorial Arboretum includes examples of several natural ecosystems found in northern Wisconsin. Some, like Mahon Woods, existed before the arboretum was created. Others, like the Oak Savanna were restored important ecosystems that had been destroyed when the area was converted to agricultural fields. Some features, like many of the ponds and the Keith White Prairie were constructed as outdoor laboratories for UW Green Bay students and faculty.

Keith White Prairie

The Keith White Prairie was created in 1973 on the north edge of South Circle Drive. It now covers eight and one half acres of the arboretum. It is maintained through periodic prescribed burns that mimic natural fire disturbances. Dominant grasses include Big bluestem, Indian grass and Switch grass. Some of the flower species include yellow cone flower, prairie dock, lupine, black-eyed Susan, spiderwort, and false indigo.

Mahon Woods and Creek

Mahon Woods is a remnant of the diverse forests that once covered nearly all of Brown County. The upland portions are dominated by mature oaks (Quercus alba, Quercus rubra), in some places with an understory of Sugar Maple (Acer saccharum), a shade-tolerant tree that eventually should become a dominant species in this forest. A few large White Pines (Pinus strobus) are conspicuous above the canopy of deciduous trees. Other portions of the forest are younger and have a mixed tree species composition, including the species listed below. Altogether about 59 species of trees and shrubs are known from Mahon Woods, along with a much greater number of herbaceous species in the ground layer. The spring wildflower displays here are spectacular during May.

Niagara Escarpment

We are fortunate to have an exposed region of the Niagara Escarpment on the east side of the Cofrin Arboretum where the trail steps down behind the observation tower and then runs along the cliff edge.  The area was quarried and you can still see where piles of tailings were left and where slabs of limestone were cut from the cliffs.

Oak Savanna Restoration Plots

In 2000 and 2001 two large areas of old field and farmland along Scotwood Drive were transformed into oak savanna. The areas were seeded with a prairie mix. Bur oak (Quercus macrocarpa) and black cherry (Prunus serotina) saplings were planted to augment existing Hills oak (Q. ellipsoidalis) at the site. Savannas are grassland areas with scattered trees and shrubs that are transitional between open grasslands and woodlands.  The characteristic habitat consists of scattered trees in a matrix of grasses and herbs, creating a "park-like" environment. 

Sager Tract

The Paul Sager Tract includes 19.99 acres located in the far northwestern section of the Arboretum. The Sager tract includes 2 ponds and associated wetlands and there are several small natural springs on the slopes. Footpaths provide access to the site and there are excellent views of the campus from the higher portions as the tract meets the forest along the Niagara Escarpment to the east. Most of the rest of the parcel is in the process of being converted to forest. It is bordered on three sides by existing Arboretum communities, including pine plantings and wetlands to the west. It is named for Emeritus Profess Paul Sager who was the first director of the Cofrin Arboretum.

Succession Plots

Beginning in 1984, ½ acre plots in the farm field, north of the UW--Green Bay soccer stadium, were systematically removed from cultivation. During each successive year until 1991, an additional ½ acre plot was set aside; since then, plots have been established at two year intervals. In 2001, the field consisted of 13 experimental plots ranging in age from 2 to 17 years of natural succession. The original project was planned to last 20 years, but that has been extended. Beginning in 2003, as space became limited, the schedule was changed so that a new plot was created every other year.