Vegetation of Upham Woods

Vegetation of Upham Woods

According to the 1851 Federal Land Survey, the vegetation vicinity of Upham Woods included oak savanna on the flat, sandy upland plains, and mixed forests of maple, oak, birch, cedar, and pines on the slopes of the ridges and the steep banks of the Wisconsin River. Most of these elements, excluding oak savanna, are still found on site today. The current vegetation of Upham Woods is a combination of relatively undisturbed natural plant communities. The natural vegetation contains elements from both southern and northern Wisconsin communities. This combination in a small area makes the site unique and ideal for research and teaching (Aber, et al. 1985).

The North Shore is dominated by forests of white oak and white pine. Blackhawk Island is also generally wooded with a mosaic of different community types including areas dominated by 1) red oak, white pine, and white oak 2) red and white pine with some red oaks 3) red oak, white oak, sugar maple, and basswood 4) hemlock with some yellow birch and white cedar 5) white oak, white pine, and red maple 6) river birch, cottonwood and red maple. Big tooth aspen is dominant in two small areas which were once logged and plowed for field crops (Aber, et al. 1985).

The mainland is dominated by a varying mix of white and red oak and red and white pine. The plantings around the buildings include various species and do not necessarily relate to one another or to the natural vegetation of the site.

Skunk Cabbage Gulch, Rockfall Gorge, and Spring Gulch contain some of the most interesting vegetation on the site. Upham Woods is one of the best places in Wisconsin to study ferns as nearly 1/3 of the state’s known taxa can be found (Aber, et al. 1985).

In 1996, plant surveys of the island and surrounding natural area revealed several rare plant species populations (O’Malley et al., 1996). These include:

Asplenium trichomanes

Maidenhair spleenwort

Special Concern Species

The small fern was first recorded in the Dells in 1867. It prefers cool, shaded cliffs, usually near water. Asplenium trichomanes is nearly ubiquitous throughout the Upper Dells river corridor due to an abundance of appropriate cliff habitat. In comparison to other known maidenhair spleenwort sites in the state, the Dells embrace the largest, densest population known in Wisconsin.

Dryopteris fragrans

Fragrant fern

Special Concern Species

Literature and herbarium accounts indicated this uncommon plant was once fairly widespread in the Dells where it was collected extensively for its sweet odor. However, intensive searches along the Wisconsin River in 1995 found only 2 small population growing on semi-shaded cliffs.

Gnaphalium saxicola

Cliff cudweed

Threatened Species, Proposed Endangered Species

Once believed to be merely a variety of a more common plant, research has determined it to be a distinct species.  Most notably, it is endemic to southwestern Wisconsin; it’s found nowhere else in the world but in the valley of the Kickapoo River and in the Dells, where it was first collected in 1866. It is believed that the Dells population is the largest, most viable anywhere on the planet. Cliff cudweed prefers slightly shaded sandstone

Primula mistassinica (var. noveboracensis)

Bird’s-eye primrose, arctic primrose

Special Concern Species

Bird’s-eye primrose is a boreal species first collected from the Dells in 1886. It is restriced to moist, shaded, sandstone cliffs and ledges and is always found in close proximity to the river.

Solidago sciaphila

Cliff goldenrod

Special Concern Species

This plant prefers dry, open cliffs and other rocky/sandy areas. In the Dells, cliff goldenrod is found at many location and is locally common here. It grows with other dry prairie species and cliff dwellers. The Dells is an important site for this species owing to the large amount of protected, continuous habitat.

Sullivantia sullvantii

Sullivant’s cool-wort

Special Concern Species

Sullivant’s cool-wort grows in crevices of cool, moist, shaded cliffs, although it can tolerate some sun. Six subpopulations were located in the Dells. Taken as a whole, the population is significant at the local to regional level. All relatives of this species at found on cliffs mainly in the Rocky Mountains.

Huperzia porophila

Rock clubmoss

Special Concern Species

Rock clubmoss is found on moist, shaded cliffs in mixed conifer-hardwood forests.

Aplectrum hyemale

Putty root, Adam and Eve Orchid

Special Concern Species

Putty root is found in rich woods, north- and east-facing slopes, and in low, flat areas. Blooming occurs May through June; fruiting occurs June through September.

During another survey of Blackhawk Island also in 1996, several distinctly different habitats were identified (Iltis et al, 1996). These include:

  1. Prairies: on sandbars and old river channel banks, as well as behind the cabins on the mainland, and on small prairie patches on the rim of the sandstone bluffs overlooking the river. Most of the species here have western affinities
  2. Pine Woods: of white, red, and jack pines, growing on about three sides of the island, as well as behind the cabins where jack pines are succeeding weeds and prairie fauna.
  3. Maple Woods: on top and in the center of the island, very rich in species of mesophytic herbs, these mainly with southern affinities.
  4. Hemlock Woods: mainly on rocky sandstone cliffs and slopes overlooking the Narrows of the Wisconsin River. On the north and east sides of Blackhawk Island.
  5. Sandstone Cliffs: on the northern and east sides of the island. These cliffs are particularly interesting. Where wooded, they are cool and moist offering habitat for many ferns and boreal species. On the level of the cliffs, on the every margin, are a number of typical bog species such as Gaylussacia baccata, the huckleberry, and Ledum groenlandicum, Labrador tea, which are able to grow there, high and dry due to the pronounced acidity of the sandstone.

A full plant species list of Blackhawk Island from this survey is available upon request.

Various succession has been occurring as well as the introduction of invasive species. On the mainland, most of the understory is characterized by prickly ash, buckthorn, Rubus sp., and honey suckle. Other invasives that are present include garlic mustard, crown-vetch, and bird’s foot trefoil. Steps are being made to control these species.

On Blackhawk Island, invasive species have made relatively little impact. The largest impact on the island has been made by Japanese barberry. There have been only two buckthorn saplings discovered on the island and were promptly removed. Garlic mustard has also been found on the island, but in very small populations (less than 10 plants). These populations are currently being monitored and removed.



Aber, John, et al. Upham Woods Master Plan 1985. University of Wisconsin-Extension, 1985, pp. 1–35, Upham Woods Master Plan 1985.

Iltis, Hugh H, et al. A Preliminary Checklist of the Ferns and Seed Plants of Upham Woods, Blackhawk Island, Juneau County, Wisconsin. Edited by Ronald Liesner et al., Herbarium of the University of Wisconsin – Madison, 1996.

O’Malley, Dave, et al. “Dells of the Wisconsin River State Natural Area Master Plan and Environmental Assessment.” Dells of the Wisconsin River State Natural Area Master Plan and Environmental Assessment, Wisconsin Dept. of Natural Resources, 1997, pp. 1–53.

Maidenhair Spleenwort (Asplenium trichomanes)

Pink Lady Slipper, Moccasin Flower (Cypripendium acaule)

Rattlesnake Plantain (Goodyera pubescens)