Dukes Experimental Forest

The Dukes Experimental Forest was established in 1926 and is located about 25 km southeast of Marquette, Michigan. There was a minor amount of white pine and elm logged during the early 1900s, but the remaining forest was not cutover during European settlement. In 1974, a research natural area (94 ha) was established within the forest’s boundaries.

Climate

Average annual precipitation on the Dukes is about 86 cm and is distributed evenly through the year. Lake-effect snowfall is considerable and averages 355 cm per year, with up to 760 cm some years. Proximity to Lake Superior results in a cool lacustrine climate, with moderated minimum and maximum temperatures. Average annual temperature is around 5 °C, and the growing season averages 110 days.

Soils

The Dukes is on a ground moraine deposited by an advance of the Green Bay lobe as it moved southward from the Lake Superior Basin. Dominant soils are the well-drained Munising sandy loam, somewhat poorly drained Skanee sandy loam, poorly drained Angelica sandy loam, and Linwood muck.

Vegetation

The uplands of the Dukes are dominated by northern hardwoods and eastern hemlock-hardwoods. Hemlock dominates the somewhat poorly drained soils and northern white-cedar, spruce and ash dominant the poorly drained soils and muck. The forests are largely in late successional status.

There are no on-site facilities.

Lat. 46°21′ N, long. 87°10′ W

Research, Past and Present

Research began on the Dukes in the 1920s and was very active until 1981 while the Marquette office was open. Studies consisted of stocking levels of hardwoods and swamp conifers, cutting cycles, regeneration, and cutting methods of northern hardwoods. A limited number of long-term studies continue today.

Major Research Accomplishments and Effects on Management

Research results from the Dukes have been used to develop management guides for northern hardwood forests in the Lake States. These guides are widely applied throughout the region. The Dukes is also an excellent demonstration area for landowners and land managers interested in managing northern hardwoods. From studies on the forest, the only proven sustainable uneven age structure for managing northern hardwoods was developed. This structure (the Arbogast Guide) is applied on millions of hectares of northern hardwoods in the Lake States.

Research Opportunities

There are research opportunities to study the silviculture and ecology of all the vegetation types on the Dukes. There also are opportunities for comparing treatments that have been applied since the 1920s. Much of this is managed old growth, of which little remains in the Lake States. The RNA is available for nondestructive research in old-growth northern hardwoods.