Introduction Prairies, a plant community dominated by grasses, were an integral part of the

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1 A Study of the Abundance, Distribution, and Species of Trees at Ipswich Prairie By: Derek Lancour, David Fuller, and Calen Wirth, Advisor-Dr. Rhea Presiado Abstract The study of abundant tree species at Ipswich Prairie serves as vital information to the Wisconsin Department of Natural Resources. This study exposes the number, types, and distribution of woody tree species at Ipswich Prairie. Results show that the most abundant tree species at Ipswich Prairie is the Cottonwood, followed by the Pin Cherry. These findings remain consistent with previous studies conducted at the prairie and prove that the presence of woody species is still a problem in the maintenance of the prairie. Now that these species have been identified and located, steps can be taken to return the prairie to its natural state. Introduction Prairies, a plant community dominated by grasses, were an integral part of the North American ecosystem (Curtis, 1959). They ran continuously from the foothills of the Rockies to the Mississippi valley and from the southern tip of Texas north into Canada. The prairies once covered 250 million acres of North America s interior before European settlement (Smith, 2001). Over 90% of the total prairie land has been cultivated or left to natural succession and is now woodland (Bellar & Maccarone, 2002). With prairie land area dwindling, conservation and preservation of these ecologically important landscapes has become a timely issue. Wisconsin was one of the first states to protect prairies. The University of Wisconsin has maintained the Faville Prairie Preserve near Lake Mills since 1840 (Curtis, 1959). Of the over two million prairie acres once in Wisconsin, much has been destroyed for agriculture and only several thousand acres exist on remnant, isolated, protected sites (Curtis, 1959). Of these sites, Wisconsin has examples of all five different types of prairie: wet, wet-mesic, mesic, mesic-dry, and dry. Each prairie type has its own floristic identity which has a list of indicator species that must be present in the field in certain proportions of the overall vegetation (Curtis, 1959).

2 Ipswich Prairie, State Natural Area (SNA) #195, is located in Southwestern Wisconsin and is the largest remnant deep soil mesic prairie left in the state (Figure 1). The site has been owned by the Wisconsin Department of Natural Resources (WDNR) since 1984 (SNADS, 1984). The Prairie was once a railroad right-of-way which is not uncommon because the fires started by the trains often preserved the prairie by keeping woody species from invading (Curtis, 1959). Since the first efforts to reestablish prairie land at the SNA in 1986, little has been done to control invasive species other than a burn in However, in November of 2006 the WDNR plans to burn Ipswich and remove brush and trees to improve the natural area for native flora and fauna. The focus of this study will be on the woody tree species of Ipswich. It will determine the most abundant woody species at Ipswich and the general distribution of the trees throughout the prairie. Ipswich Prairie Kilometers Figure 1. Arial view of Ipswich located in Lafayette county Wisconsin. The research questions of this study are: Question 1: What is the most abundant woody tree species at Ipswich Prairie? Hypothesis: The most abundant woody tree specie at Ipswich Prairie will be Populus deltoids (cottonwood). N

3 Null Hypothesis: The most abundant woody tree specie at Ipswich Prairie will not be Populus. deltoids. Question 1: What is the distribution pattern of the most abundant specie? Hypothesis: The distribution of Populus deltoids will be clumped throughout the prairie. Null Hypothesis: The distribution of Populus deltoids will not be clumped throughout the prairie. Materials and Methods Field Surveys Fieldwork was conducted at Ipswich Prairie located 4.8 km south of the city of Platteville on Ipswich Road. It is a linear prairie 1.9 km long ranging in width from 40.5 meters on the south end to only meters wide on the north end (Hoffman, 1986). Three sites were examined, during October 2006, for the presence and abundance of woody species. We divided the prairie into three sections (north, central, and south) based upon prairie orientation, each portion approximately.5km long (Figure 2). In each section, a team of individuals visually surveyed the prairie beginning at the northernmost point and proceeded toward the southern boundary. At each woody plant the following data was collected: GPS location, genus, and species. The trees were identified using two identification guides (Little, 1980; Watts, 1991). On the first day of research, trunk diameters were collected at ground level for 40 Populus deltoids and 50 Prunus pensylvanica, pin cherry trees. Microsoft Excel was used to convert the raw GPS data into a usable format for the ESRI Arc Map software. This program was then used to plot the GPS points on a WI DNR aerial photo of Ipswich Prairie.

4 N Figure 2. Prairie orientation: red=north, blue=central, white=south. Results The total number of trees at Ipswich prairie was Eight species of trees were identified and counted: eastern cottonwood (Populus deltoids), pin cherry (Prunus pensylvanica), smooth sumac (Rhus glabra), box elder (Acer negundo), American elm (Ulmus americana), prairie crab apple (Malus ioensis), white mulberry (Morus alba), sweet crab apple (Malus coronaria) (Figure 3). The data shows that Populus deltoids 46%, Prunus pensylvanica 27%, and Rhus glabra 19% are the dominant tree species (Figure 4).

5 Species # of Individuals Populus deltoids 536 Prunus pensylvanica 366 Rhus Glabra 220 Acer negundo 37 Ulmus americana 6 Malus ioensis 5 Morus alba 2 Malus coronaria 1 TOTAL 1173 trees Figure 3. Chart of the species and corresponding number of individuals. 0% 0% 3% 1% 19% 0% 46% 31% Pin Cherry Cotton Wood Sumac Elm Box Elder Mulberry Praire Crab Apple Sweet Crab Apple Figure 4. Pie chart of the percent composition of species located at Ipswich Prairie. Of 40 P. deltoids trunk diameters, the smallest tree diameter was 1.0 cm and the largest was 7.0 cm. The average trunk diameter of P. deltoids was cm (Figure 5). Of the diameters of 50 sampled P. pensylvanica trees, the smallest tree diameter for P. pensylvanica was 2.0 cm and the largest was 7.4 cm. The average diameter was 3.8 cm (Figure 6). The distribution of P. deltoids, P. pensylvanica, and R. glabra are clumped at Ipswich Prairie (Figure 7).

6 14 Cottonwood Diameters (cm) Frequency diameter (cm) Figure 5. A histogram of 40 P. deltoids trunk diameters. Histogram of pin cherry diameter (cm) Frequency tree diameter (cm) 6 7 Figure 6. A histogram of 50 P. pensylvanica trunk diameters.

7 N Figure 7. An aerial photo of the GPS locations for the three most abundant tree species at Ipswich prairie. P.deltoids= P. pensylvanica= R. glabra= Discussion The biggest concern in the management of the prairie is the large quantities of P. deltoids and P. pensylvanica. Their distributions are clustered and are taking away nutrients and space from native prairie species. Over time, the P. deltoids and P. pensylvanica populations will compete with and succeed the other native prairie species. Our data shows that two age classes of trees inhabit the prairie. The older trees, distinguished by their larger trunk diameters and few numbers, are likely the survivors of the 2004 burn at the prairie. The younger class, characterized by their small trunk diameters and large numbers, began growing after the 2004 burn. P. deltoids clumped distribution illustrates another concern in that it can reproduce through vegetative propagation, meaning that from one tree s roots many trunks can sprout. This process is problematic because a prescribed burn may kill the trunk meanwhile enabling the live roots to grow new trunks. The data from the plotted GPS points show that the three most

8 abundant species exhibit spatial autocorrelation, meaning that similar species are clumped together. This situation is important to the Wisconsin DNR because it can aid them in determining methods for tree removal. Burning, a preferred method for woody species prevention and removal would be most effective and efficient on the smaller diameter trees (Left & Knapp, 2004). Future research on the populations could determine why pin cherry and cottonwood are the dominant species, and where the parent trees are located. More research could be done to track the trees identified in this study after the November 2006 burn to determine the survival rates and the effectiveness of that fire. This research could help prevent future infestations of trees in the prairie. Conclusions The study of abundance, distribution, and classification of tree species at Ipswich Prairie was conducted in an attempt to aid the Wisconsin Department of Natural Resources in its management of the prairie. The primary objectives in this study were to find the most abundant tree species at Ipswich Prairie and the distribution patterns of the most abundant tree species at Ipswich Prairie. The data collected states that P. deltoids is the most plentiful tree species located at Ipswich Prairie. Lastly, through the use of GPS coordinates, our data has established that P. deltoids disperses itself in aggregated patches throughout the prairie. The data collected will be essential in the DNR s future management of the prairie. The DNR should be strongly advised to administer burnings and brushings more frequently to prevent woody species infestation in addition to conducting spot cuttings to remove larger trees which are unaffected by burnings and brushings.

9 Works Cited Bellar, C. A. & Maccarone, A. D. (2002) The Effects of Prairie Habitat Loss and Land Use Changes on Loggerhead Shrike Populations in Kansas, Transactions of the Kansas Academy of Science, 105 (1), Curtis, J. T. (1959) The Vegetation of Wisconsin. University of Wisconsin Press. Hoffman, R. (1986) The Probably Effects on the Bird Populations of Ipswich Prairie with the Removal of Woody Vegetation and Exotic Plants. Wisconsin, Department of Natural Resources. Left, M., and Knapp, A. (2004) Woody Plant Encroachment and Removal in MesicGrassland: Production and Composition Responses of Herbaceous Vegetation. American Midland Naturalist, 153, Little, A. (1980). National Audubon Society Field Guide to North American Trees. Eastern Region, Alfred A. Knopf, Inc. Wisconsin Department of Natural Resources (1984) Scientific and Natural Area Data Sheet. (SNDS), Wisconsin Department of Natural Resources. Smith, D. D. (2001). America s Lost Landscape: The Tallgrass Prairie. Proceedings of the 17th North American Prairie Conference, Watts, D. (1991) Tree Finder: A Manuel for the Identification of Trees by their Leaves. National Study Guild Publishers Rochester, New York.