Black Earth Rettenmund Prairie
Sweet clover control is our major task at the moment. For details of summer work days call Kathie or Tom Brock at 608-238-5050 or send an email to kmbrock@charter.net
Ownership
Black Earth Rettenmund Prairie is owned by the Prairie Enthusiasts and
managed by the Empire-Sauk Chapter. Stewards are Tom and Kathie Brock.
Location
Dane County. T8N-R6E, Section 27 SW¼. 16 acres. From
the intersection of Highways 78 and KP in Black Earth, go west on KP 1.1
miles, then south on F 0.25 mile, then west on Fesenfeld Road 0.2 mile
to a small parking area south of the road. If the parking lot is occupied,
park on the north side of the road.
Public Access
The Prairie is open to the public for hiking throughout the year. Due
to the small size of the preserve, hunting is not permitted. Stay
on the marked trail (see map).
Volunteer Workdays
Work days are usually the first Saturday of the month, from 9 AM until
noon. However, the schedule may be modified if a holiday weekend is involved.
For details on work days, contact Willis Brown at 608-278-9308 or by email
at WEBrown3@hotmail.com. More details below.
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| Boy Scouts helping to pull Queen Anne's lace, an exotic invasive plant, at Black Earth Rettenmund Prairie. |
Field Trip
A regularly scheduled field trip is held the second or third Thursday
of June, under the joint auspices of the Prairie Enthusiasts and Madison
Aububon Society. This is an excellent time to see the early summer flora,
and especially the extensive displays of Lilium philadelphicum.
In 2008 this trip will probably be held June 19. Please call Tom or Kathie
Brock at 608-238-5050 or check this website for confirmation.
The mid-June field trip is popular. Tom Brock explaining the history and management of Black Earth Rettenmund Prairie on June 15, 2006.
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| Volunteers sorting out seeds collected at Black Earth Rettenmund Prairie 17 Oct 2007 |
Description and Significance
The site is one of the few remaining examples of a dry-mesic prairie in
Wisconsin. In contrast to other prairie preserves in the Driftless Area,
this site is on relatively level terrain. It has an outstanding assemblage
of plants including several rare and uncommon species. Because of its
proximity to Madison, and its easy access, the preserve has great educational
value.
Black Earth Rettenmund Prairie is located on a low knob and ridge. It is characterized as dry-mesic with areas ranging from dry to nearly mesic. It harbors a rich flora of over 130 native prairie plant species. It is predominantly a forbs-rich prairie. The forbs are very diverse and include such showy species as pasque flower, lead plant, shooting star, compass plant, blazing star, purple and white prairie clover, wood lily, wood betony, false toadflax, butterfly milkweed, coneflower, black-eyed Susan, sunflowers, asters, and goldenrods. Of significance is the occurrence of pomme-de-prairie (Pediomelum esculentum), white camas lily(Zigadenus glaucus), Carex richardsonii, rough-stemmed false foxglove (Agalinis gattingeri), and a rare aster hybrid. At one time there was Hill's thistle (Cirsium hilli) but this has not been seen recently. Grasses are dominated by big and little blue stem, Indian grass, needle grass, and prairie dropseed. (A detailed species list will be supplied upon request. Call Tom Brock at 608-238-5050.
Flowers of Black Earth Rettenmund Prairie: Photo gallery
In addition to these rare plants, a threatened butterfly, the regal fritillary (Speyeria idalia) has been observed, as well as striped hairstreak (Satyrium lipdrops).
This prairie was once rated among the top ten natural areas in Dane County in private ownership. It was used by plant ecologist John Curtis as an outdoor classroom and was one of his prairie sites in his classic book Vegetation of Wisconsin.. The University of Wisconsin-Madison herbarium has numerous entries of plants collected at this site, some dating back many years. The earliest collections that can be positively identified from this site are those of J.R. Heddle, which were made 3 August 1916. Other collections were made in 1925, 1931, 1950, 1959, 1960, and 1965. The latter collections were made by Professor Hugh H. Iltis, who also carried out the first controlled burn in 1965.
The preserve is in the drainage basin of, and is within site of, Black Earth Creek, one of the outstanding trout streams in southern Wisconsin.
The quality of the prairie varies over the preserve, with the highest quality being located in the northern portion.
Land Use History and Permanent Protection
Based on the original land surveyor records, the presettlement vegetation of the preserve was probably treeless prairie, except in the southwest corner where it graded into oak savanna or open woodland.
The preserve was once part of the William Rettenmund farm but it was probably never plowed. The owner, William Rettenmund, preserved this prairie for over 40 years. Mr. Rettenmund granted conservationists permission to study the prairie and to conduct management activities, including controlled burns. The first plant survey was done in 1969. However, Mr. Rettenmund had observed the marked "decline" in the prairie during his ownership and both he and his wife had a genuine interest in seeing it preserved and managed. It was because of Mr. Rettenmund's deep concern in seeing the prairie preserved that he sold the land to the Nature Conservancy at below market value.
Initial contact with Mr. and Mrs. Rettenmund was made by the State Natural Areas office in 1981, and serious discussions about purchase were made in 1984. At that time, about 40% of the site had been taken over by shrubs, aspen, and other trees. The property was acquired by the Nature Conservancy in 1986, using funds provided by Madison Audubon Society. Later the same year it was dedicated as a State Natural Area, insuring its continued protection.
Many descendants of William and Agnes Rettenmund still live in the area. Members of the family pose next to the State Natural Area sign at the 2005 field trip.
Early Management Activities
Soon after acquisition, restoration work was undertaken by the Nature Conservancy. Controlled burns were carried out at regular intervals. Hand pulling of weeds and cutting of aspen, sumac, honeysuckle, and buckthorn was carried out. Trees along the perimeter of the preserve were cut and the stumps treated with Garlon 4. Cherry trees, honeysuckle, and buckthorn on neighboring land have also been cut with the owners permission. The fence along the neighbor's pasture running east-west was rebuilt by the Nature Conservancy.
In the late 1990s, modest volunteer work parties were carried out, once or twice a year. These involved primarily brush clearing, with herbicide treatment. However, these minimal volunteer activities were insufficient to control woody growth. By the end of the 1990s, brush and tree growth on the south part of the preserve had become excessive, and prairie vegetation was being crowded out. Work on this end of the preserve was initiated again in 2000. Using support from the Savanna Oak Foundation, Inc., private contractors were hired to cut and treat vegetation. Between this work and annual controlled burns, prairie vegetation responded well and thrives.
Management Activities by the Prairie Enthusiasts
Beginning in 2003, management was taken over by the Prairie Enthusiasts under an agreement with the Nature Conservancy. At this time, more intensive restoration work was undertaken, under the guidance of Kathie and Tom Brock and with financial support from the Savanna Oak Foundation, Inc. Ownership (title) to the Prairie was transferred by the Nature Conservancy to the Prairie Enthusiasts in August 2007. (Download the press release.)
Weed control During the hiatus of management in the mid to late 1990s, several weed problems became exacerbated.
White sweet clover The most serious problem was white sweet clover (Melilotus alba), which was wide spread throughout the preserve, but greatest in the “saddle” and north units. Initially infestations were so heavy that they had to be mowed, with hand pulling of any outliers. Prairie Enthusiasts workdays were held throughout the sweet clover season(June-August), with additional weekly workdays on Friday evenings in July. Since 2006 only hand pulling has been needed, but as much as 300 worker-hours (both volunteers and paid contractors) have been needed to control the problem. Summer workdays are scheduled by the Prairie Enthusiasts as needed. By the year 2008 the worker-hours had reduced to about 175, and it is hoped that within a few more years the problem will be eliminated.
Certain areas of the "saddle" area have been heavily infected with sweet clover (July 2005 photo). When a patch is this large, hand pulling is not an option. Because sweet clover is a biennial, mowing at the time of full flower is effective in eliminating the patch. However, there is a long-lived seed bank, so continual monitoring and control is necessary for many years.
Wild parsnip (Pastinaca sativa) was also a problem in the early 2000s but it has now been mostly controlled by hand pulling.
Brush control Especially along the fence lines, but also in central parts of the South Unit, large populations of exotic honeysuckle had developed. Many winter workdays (volunteers and contractors) were held in 2002-2005 to remove these shrubs. Both brush cutters and hand loppers were used, and all cut stems were treated with glyphosate herbicide. Other woody plants that continue to be controlled include buckthorn, grape, and spreading dogbane.
Controlled burns An annual controlled burn is carried out by the Prairie Enthusiasts, usually in late March or early April. The preserve has been divided into three burn units (north, saddle, south). The saddle is burned on alternate years, together with either the north or south unit.
Prairie Enthusiast controlled burn of April 2, 2007. Burn boss Rich Henderson outlines the purpose of the burn and assigns tasks.
The Prairie Enthusiast burn crews are all well trained and experienced. Most of the people on this burn had participated in earlier burns at Black Earth Rettenmund.
On this burn, only the north unit was burned. A fire break separating the north unit from the saddle had been mowed the previous fall.
What the well-dressed burner wears. Two-way radios are used to keep in constant communication with the line boss and the burn boss.
Gateway Prairie Near the entrance to the preserve is a small area that had at one time been plowed and had developed into a field primarily of smooth brome grass (Bromus inermis). When the Prairie Enthusiasts began managing the preserve, restoration of this field began. Originally, restoration was done simply by burning and overseeding with species collected elsewhere on the preserve. When it became clear that this approach would require many years for success, the field was sprayed with glyphosate herbicide in the early spring. Timing of the herbicide treatment was such that the native prairie species (which are warm season plants) had not developed yet, but the cool season (nonnative) species were already growing. This procedure was very effective and most of the smooth brome and other cool season plants were killed.
Soon after the herbicide treatment, the field was seeded with native species. The native species are gradually taking a foothold. Because this field now consists of predominantly prairie species, it is called the “Gateway Prairie.”
Seed collecting The rich flora of Black Earth Rettenmund Prairie makes seed collecting a delight. The seeds collected are planted in the Gateway Prairie and in areas of the South Unit where brush control had been carried out. See the seed collecting schedule below. In addition to regularly scheduled seed collecting days, special days are scheduled as needed.
Volunteers assembling to collect seeds on an early fall day.
Workdays are scheduled for the first Saturday morning of the month, throughout the year, with occasional special nonscheduled days when the need is present. However, modifications of the schedule are made if the Saturday comes on a holiday weekend. An email notification list is maintained, and those interested are invited to submit their email addresses. Call Willis Brown at 608-278-9308. (Email addresses are never given to others.) Always call before coming to a workday, as weather or other factors may make it necessary to cancel the workday.
Prescribed burns are another major volunteer activity. Our prescribed burn is usually held at the end of March or early April. Call Tom Brock in late March at 608-238-5050 for information. Volunteers are welcome either as participants or observers.
Black Earth Rettenmund Prairie is in the watershed of Black Earth Creek,
a Class I trout stream that is highly productive and a popular recreation
area.
Black Earth Creek has been called one of the top 100 trout streams in
the United States. It is a beautiful classic, coldwater, spring-fed trout
stream. The Creek is the focus of extensive protective management activities,
and is recognized as a fragile but beautiful watercourse. Increasing urbanization
of the area west of Madison and Middleton has raised concerns about the
fate of Black Earth Creek. The Black Earth Creek Watershed Association
is a nonprofit membership-based organization whose goal is the protection
of this important trout stream.
Map of the Black Earth Rettenmund Prairie (Download a PDF version)
