Forest Type along Pike River Petrifying Springs Park Kenosha, Wisconsin. Keith Chiarugi

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1 Forest Type along Pike River Petrifying Springs Park Kenosha, Wisconsin Keith Chiarugi Senior Thesis Carthage College Department of Geography December

2 Abstract This paper explores the type of forest that the Pike River runs through while running through PetrifYing Springs Park in Kenosha, Wisconsin. Along the river there should be a riparian forest that gradually becomes a southern mesic forest as it travels upward along the gradient. This paper explores the different tree types that are along the Pike River and as it moves upwards away from the river to 22 meters away. This paper concludes with data analysis on the types of trees that occupy the forest along with their density and dominance relative to the other trees along those same gradients. 2

3 Literature Review of Senior Thesis Ecotone Ecotones are very interesting spaces of land to scientists. Ecotones are transitional areas between adjacent ecological systems (Risser, 1995). The study of ecotones started over 60 years ago, but not until the 1970's did any governmental programs start focusing on ecotones (Risser, 1995). Although the concept of an ecotone began as a static transitional zone, the concept has evolved into a recognition that ecotones move in a dynamic landscape, controlling material movement through watersheds (Risser, 1995). An ecotone varies in scale from a narrow transition zone to very broad scale transition zone. Ecotones generally occur under two conditions. First, ecotones exist at steep gradients in physical environments, directly affecting ecological processes and the distribution of organisms. Second, they occur in responses to gradual gradients in the environment, causing large changes in the ecosystems dynamics and in the distribution of dominant species (Risser, 1995). An ecotone can be affected by many things, such as climate change or human impacts, since it is an area of"range limits" within the forest (Malanson, 1993). Many different studies have been done concerning ecotones. Ecotones can differ in their appearance. Some of these different ecotone study areas have been where salt water meets with fresh water in San Francisco Bay, and where the rainforest transforms into a savanna in Africa. This research project focuses on a much smaller ecotone between the riparian zone and the southern mesic forests in Petrifying Springs Park in Wisconsin. 3

4 Riparian Ecosystems Riparian ecosystems are some of the most diverse and productive portions of land. Often they are among the frrst landscape features to show impact from management activities and reflect overall watershed condition (National Riparian Service Team Website, 2001). A riparian zone is an area of forested land near a body of water which has the transition of aquatic to land ecotone taking place (Chesapeake Bay Program Website, 2001). A riparian zone is also directly influenced by the river and the entire river related processes. Some riparian zones also contain lakes, ponds, and other wetlands. A riparian zone is also an ecotone in two ways. It is an ecotone in the aquatic to the riparian zone and it is also an ecotone in the riparian zone to the upland region (Malanson, 1993). In this study the ecotone is one of riparian changing to southern mesic forest. Riparian zones are also used as travel methods for plants and animals. Many plants use the riparian zone as a unique method of seed spreading. Some trees only grow on riverbanks and have seeds that are made to flow down the waterways, taking their seeds far away from the actual tree species (Thinkquest.org Website, 1998). The trees of riparian zones are usually the biggest of the forest since the soil is the best of the forest there. This happens because the riparian zone is at low elevations and all the nutrients for the uplands flow downwards to the riparian zone (Thinkquest.org Website, 1998). There are some tree species that survive better in riparian zones then others. Some of those species are: Birch, Ash, Sycamore, Dogwood, and Willow (Department ofnatural Resources, Wisconsin Website, 2002). 4

5 Southern Mesic Forest Ecosystems The southern mesic forest is most commonly found growing on well drained soils, as well as on upland slopes. These forests grow where the environment is not extreme and usually where there is a lot of cover and not much sunlight. With the density oftrees and the resulting lack of sunlight, many other plant species can not grow into these forests. The tree density also increases the humidity of the forest and gives quick decomposition times resulting in more rich nutrients available to the forest (Woodland Communities Website, 2000). Some of the dominant trees that inhabit the southern mesic forest are maple, basswood, beech, and elm. Maples dominate southern mesic forests. These trees are extremely shade tolerant as seedlings and saplings, tolerating shade completely at the forest floor (Curtis, 1959). Even though maples are highly flammable, the closed canopy of trees in a southern mesic forest keeps the forest humid enough to deter forest fires (Curtis, 1959). The majority of Petrifying Springs Park is a classic example of a southern mesic forest in Wisconsin. Gradient Analysis Gradient analysis is a widespread method of investigating vegetation changes. Invented by Ramensky and Gause in 1930, gradient analysis was not used extensively until after 1950 for ecological research (McPherson Website, 2001). Two types of gradient analysis are, indirect and direct. If only species data is being used to determine the gradient then it is called indirect gradient analysis. In direct gradient analysis though, species and environmental data are used together to determine the gradient (DeAth, 1999). 5

6 In gradient analysis, data are plotted along environmental axes which can be indirect, direct, or synthetic (McPherson Website, 2001). This data is trying to analyze a change in the community structure and to fmd how species are distributed (UNL V Website, 2001). Species are not always perfectly clustered along the gradient. Sometimes there are sharp transitions along the gradient as well. These sharp transitions are possibly examples of the competition that is occurring on the forest floor (UNL V Website, 200 I). Gradient analysis requires sampling at regular intervals along the gradient that is being studied. Gradient analysis can be done at many different scales. The gradient analysis used in this study quantifies the change from riparian forest to southern mesic forest at Petrifying Springs Park in Kenosha, Wisconsin. Point- Center - Quarter Method The specific gradient analysis method used in this project is the point- centerquarter method (Cottom and Curtis, 1956). This method was frrst used in the mid 1800's for the Federal surveyors to make the original surveys of government lands. It has since been used for ecological purposes. This method is used to determine the relative importance of various trees in a community (Mitchell, 2001). Along a transect line, sampling points are located at a standard distance. Each sampling point is considered the center. From that center, the surrounding area is divided into four quadrants. Next, the closest species inside each quadrant is sampled. The distance from the point to the closest species is measured as well as the species and the basal area (Cottam and Curtis, 1956). This method is designed to estimate species density, mean distance, relative density, and basal area per tree (Arizona Rangelands Website, 2001). 6

7 The objective of this research is to quantify ecotonal changes along the Pike River in Petrifying Springs Park. The hypothesis is that a sharp ecotone, riparian tree species to southern mesic tree species, spatial boundary exists along the gradient from the Pike River edge to the uplands. 7

8 Methodology for Senior Thesis Study Area This study was done in a unique area of a forest in Wisconsin. The Petrifying Springs Park in northern Kenosha is a southern mesic forest, one of the most southern examples ofthis biome. Petrifying Springs has some ofthe largest stand of white cedar in the county as well as the largest basswood, maple and black walnut trees in Kenosha County (Tanzilo, 2001). The 360-acre park is named for the geological feature at its southern end, the contact springs, resulting from rainwater gurgling up through rock. The water leaves behind a rocky-looking substance but it is not actually stone (Tanzilo, 2001). Southern mesic forests grow on well drained soils upland soils. These forests typically occur in areas with few environmental extremes (Woodland Communities Website, 2000). Some of the dominant trees that inhabit a southern mesic forest are sugar maples (Acer saccharum), basswood (Tilia Americana), beech (Fagus grandifolia), and elm (Ulmus Americana). These tree species are very tolerant of shade and grow well in areas with lots of cover. Beginning by a spring near Case High School in Racine, the Pike River runs for 4.75 miles until it empties into Lake Michigan in Kenosha. In regards to Petrifying Springs Park, the Pike River flows through the area and gets channeled under the road through a tunnel. When heavy rains fall the water from the Pike River can overflow the road and flood the bridge in the park (Midwest River Inventory, 2002). 8

9 Study Sites In this study, three different study sites were chosen randomly from Petrifying Springs Park along the Pike River. Each different site had one transect running from the river outward into the forest. Two ofthese transects were on the western side of the Pike River and the third transect was on the eastern side ofthe Pike River. Field Methods This study used the point- center - quarter method as its method of data analysis. As stated before, this method runs a transect with evenly spaced points located along the line. At each sampling point, four quadrats are divided from each point and the nearest plant is recorded. In this study five points were selected for each transect. The points were at 2 meters, 7 meters, 12 meters, 17 meters, and 22 meters. Each point was divided into four quadrats. For each quadrat the closest tree was used as the study species. For each recorded tree, data taken included: species, the diameter at breast height (dbh), in centimeters, how far from the sampling point the tree, direction to sampling point, and any additional comments. Statistical Methods A variety of statistics were run to test the hypothesis. First, total density of trees per hectare is found. Hectare was determined by taking the unit reference area and dividing it by the mean area, after the total density the density per hectare for each species is found, second, percentage frequency for each species was determined. This is defmed as the percentage of quarters in which a particular species was measured divided by the percentage by the total density. 9

10 Third, the absolute frequency was calculated by taking the number of points at which a species was measured in at least one of the quarters. Forth, the relative frequency is calculated by dividing the total absolute frequency and multiplying that number by one hundred. Fifth, the basal area per hectare is determined by taking the basal area per species and multiplying it by its density. It is important to note that numerical differences may occur due to rounding. Sixth, to find the relative density, take the number of individuals of a species and divide that by the total number of individuals and multiplying by one hundred. The seventh statistic is the relative dominance which is the basal area per hectare for each species is divided by the total basal area for all the species, and then multiplied by one hundred. The statistical methods are summarized in a statistic called importance values, which is the percentage of total importance each species has on the forest. 10

11 Results For the three sites, many different statistical methods were done to obtain information about Petrifying Springs Park. Table one found absolute frequency, absolute density per hectare, basal area per hectare, relative density, relative frequency, relative dominance, and the importance value each tree species had on site one of this study. Table two also found the aforementioned statistical methods. This table though, found information regarding site two and its different tree species. The second table had less information on it but the same statistical methods were used. Table three was also using the same statistical methods that table one and table two used but table three was covering site three. Table three ran into some problems concerning the findings of grass and not a tree species. The slight difficulty was dealt with and table three shows that in its information. l1

12 Discussion Each different site was able to show different things concerning Petrifying Springs Park in Kenosha, Wisconsin. Site one had many interesting things involved in its findings. At every point along the transect there was at least one quadrant that contained maple trees while all the other trees from site one were found at either one or two different points along the transect. With maple trees being so prevalent in their absolute frequency it was no surprise that their absolute density was also the highest per hectare compared to the other four tree type found at site one. Maple trees had an absolute density of 1221 trees per hectare while three of the other four trees had absolute densities of244.2 per hectare. Only beech trees had a higher density then At 488.4, beech was the second densest tree per hectare from site one. The findings for the basal area for each tree were similar in that the highest basal area per hectare was the maple tree again with a basal area of The other trees were not as uniform as they had been before though. The birch tree was the next highest in basal area with This shows that although the birch only appeared one time in the data it was a tree that had more volume compared to the other trees that were in the frrst site. Basswood followed with a basal area of22.22, and the beech followed with The tree that had the smallest basal area for site one was the locust. It had a basal area of 7.57 showing that not only was there only one tree in the frrst site but the locust was had a very small volume compared to the rest in the site. The relative density had similar fmdings that were expected after looking at the previous data. 75 percent of the sites relative density was occupied by maple trees followed by the beech that had 10 percent. The other three trees had 5 percent apiece. The relative frequency of the site was also similar in findings. Maple trees again were the most 12

13 represented with 50 percent of the total. Beech followed with 20 percent and the other three trees, birch, locust, and basswood each had 10 percent. Relative dominance was identical to the findings of the basal area per hectare for each species. Maple trees covered 38 percent of the basal area and birch had a 23 percent finding. Basswood and beech had 17 and 16 percent respectively. Locust had the smallest relative dominance with only a 6 percent total. The importance value of each tree species held in the similarity to the rest of the findings. The maple trees had an importance value of 163 out of300 while the next highest was the beech with a value of 46. Birch followed with 38, and basswood had 32. The smallest value was the locust with a value of21. It can be concluded that site one contained mostly maple trees. While the maples were not as large in volume relative to their high amount, they still were the highest in volume for site one. Site two was not as dominating as the site one was. There was less variance of tree species having only three different tree types in the site. Maple trees were found in all five of the points while American elm was found in four of the five and basswood were in only three of the points. The absolute density of the trees was similar to their frequency. Maple had a density of per hectare, American elm had a density of and basswood had The basal area of site two was very different to the frequency and the density. The American elm had the highest basal area with This was followed by the basswood that had a basal area of The maple had the lowest basal area with These fmdings show that despite maples having the highest amount of trees in the site they were the smallest in terms ofvolume. This could mean that there are a lot of maples but they are young and still smaller then the surrounding trees. The relative density of site two had 55 percent of the site being maples. American elm covered 30 percent ofthe site and basswood covered the remaining 15 percent. The 13

14 relative frequency went along with the relative density with maples having the highest percentage at 42 percent. This was followed by the American elm at 33 percent, and the basswood which had 25 percent. Relative dominance of site two was quite different. American elm dominated 50 percent ofthe site and basswood had another 41 percent. Maple trees had only 9 percent of the dominance yet still had the most trees in the site. The importance value of the site was even more different then all the other findings. American elm was the highest with 113 out of300, but was followed up by the maple having a 106. Basswood was the lowest with 81. These three were very close in all the data fmdings. It could be concluded that while there were many more maples then any other they were small and young covering much less total area. The American elm was the second most recoded tree yet it was the highest in basal area and dominance. While the basswood was the least recorded and the smallest in density they were still large enough to have an impact on the surrounding trees in the site. Site three was the most complicated of the three sites. Some of the points did not have any trees in them and grass had to be substituted in its place. This did not affect the data but some of the data fmdings for grass had no data due to not being a woody species. Site three was also the most diverse in the amount of species that were in the site. Five different tree species and grass were found in the third site. Grass had to be recorded in four of the five points. Box elder was found in three of the five and beech was in two of the five. Maple, willow, and choke cherry were only found in one of the points. The absolute density was similar to the frequency with box elder having the highest at Beech had the next highest with Maple, willow, and choke cherry each had as their densities. Grass was not able to be recorded for absolute density. The basal area for each tree species was quite diverse do to the varying difference in sizes. The willow had the highest basal area with This showed that the willow was 14

15 very large, and while only fmding one in the whole site it was much larger then all the other tree species. The box elder had the next highest basal area with 49.45, and was followed by the maple at Choke cherry and beech were quite small in regard to the other trees at this site. They had basal area totals of 6.59 and 4.4 respectively. Grass was not able to have a basal area since it is not a woody species. The relative density was similar to the frequency in that grass was 50 percent of the fmdings. Box elder was the next one at 20 percent, and choke cherry and beech had 10 percent each. The remaining 10 percent was split evenly among the maple and the willow. Relative frequency was similar to the relative density since it had grass with the highest percentage at 33 percent. The box elder was the next with 25 percent. Choke cherry and the beech were both at 17 percent, and the maple and the willow each had 8 percent. The relative dominance of the different tree species was similar to the basal area of the trees. The willow was the most dominant with 64 percent ofthe data. Next, were the box elder with 18 percent and the maple with 14 percent dominance each. The beech and the choke cherry each had only 2 percent dominance. Grass did not have dominance since it did not have a basal area to take data from. The importance values of site three were very close together. This could be because while there were some trees that were recorded more often, there were also trees, like the willow, that were so large that their dominance had a big influence. Grass had the highest influence at 83 and was followed closely by willow at 77. The box elder had an importance value of63. Both the choke cherry and the beech had values of29, and the maple had the smallest value with 27. This site had many different species and great variance in sizes of these species. Having the amount of difference, density, and dominance caused most of the data to be very close when looked at as a whole. 15

16 Conclusion Many different things go into determining what kind of forest Petrifying Springs is. The assumption that the park would be a riparian forest and gradually become a southern mesic forest along the gradient from the Pike River is not what actually occurred in the park. After walking the park and then collecting data in the park it appears that the park is more of a southern mesic forest with sporadic riparian tree species throughout. Once the data was analyzed the same outcomes were shown. At each site there were maple tree species and they clearly dominated the forest as a whole. There are a few assumptions that could be made out of the data and the actual walking of the park. It is possible that over time the park has changed the direction of the rivers flow causing the river to travel through a different area of the park. This area being a southern mesic maple dominated forest. Another possibility is that the forest actually was and possibly still is a riparian forest but maple trees have been planted in the recent past and have caused the riparian trees to be pushed out or at least to be less prevalent then they used to be. This also could be both of the previous assumptions together. It is possible that the rivers flow was redirected and that more maple, or southern mesic, tree species have been planted into the area. This study could be taken further by taking more samples along both side of the river to see if these three samples are outliers or are similar to other places along the river. Direct contact with the park itself could help explain the parks makeup. This study needs to be taken further to see if the hypothesis is proven wrong, or that over the whole forest the riparian tree species actually do gradually change to southern mesic along the gradient from the Pike river outwards. 16

17 Bibliography Arizona Rangelands. December Point - Center Quarter Method. Retrieved October 21, Chesapeake Bay Program. June 8, Riparian Forest Buffers. Retrieved October 14, http :l/www. chesapeakebay.net/ripar 1.htm. Cottam, Grant, Curtis, J. T., The Use of Distance Measures in Phytosociological Sampling. Ecology, 37, Curtis, John T., The Vegetation of Wisconsin. Madison, Wisconsin: The University of Wisconsin Press. DeAth, Glenn, Principal Curves: A New Technique for Indirect and Direct Gradient Analysis. Ecology. Kuchler, A W., VegetationMapping. New York: The Ronald Press Company. Malanson, G. P., Riparian Landscapes. New York, New York: Cambridge University Press. McPherson, Guy R., Direct Gradient Analysis. Retrieved October 2, Midwest River Inventory, Midwest River Inventory. Retrieved November 6, geocities. corn/midwestrivers/wis-pike-petspgs.html. Mitchell, Kevin. July 19, Quantitative Analysis by the Point - Centered Quarter Method. Retrieved October 22, National Riparian Service Team, National Riparian Service Team. Retrieved October 12,

18 Risser, Paul G., The Status of the Science Examining Ecotones. Bioscience, 45, Symonds, George W. D., The Tree Identification Book. New York: M. Barrows and Company. Tanzilo, Bobby, May 28, Walking Wisconsin. Retrieved September 28, onmilwaukee. corn/sportsrec/ articles/hikingguide.html. Thinkquest.org, Shades of Green Earth's Forests - Riparian Zones. Retrieved October 15, http :1/library. think guest. org/17 456/riparianall. html?tgskip 1 = 1 &tgtime= UNLV: Biology 441/641 Lecture Notes, Gradient Analysis of Vegetation in Spring Mountains. Retrieved September 16, unlv. edu/faculty/wagner/fallo 1/Handouts/gradient1.PDF. Woodland Community, Woodland Community Model - Southern Mesic Forest. Retrieved September 13, /wiscinfo. do it. wise. edu/arboreturn/woodland/southem mesic forest. htm. 18

19 ..., Golf Course Malntcnnnce.Facility Sledding Dill _,- ; ~ bi:u~ontl #ll ~ I.I. )~ r---::-- ~ : ( ~R Parking Al'Cll I -====----- /

20 TABLE 1. STATISTICAL RESULTS FOR SITE #1 Site 1 (a) Absolute Frequency Total Distance= 57.23m Maples- 5 D = Mean Distance Birch \ 20 = 2.86m Beech - 2 D 2 = Mean Area locust * 2.86 = B. 19m 2 Basswood- 1 Total Density 10,000m 2 \ 8.19m 2 = 1221 trees per ha ( c) Basal Area Per ha Maples \ 15 = 22.5cm 22.5cm = *1221 = B1rch \ 1 = 39.5cm 39.5cm = *244.2 = Beech \ 2 = 22.98cm 22.98cm = *488.4 = Locust \1 20.1cm 20.1cm = *244.2 = 7.57 Basswood \ 1 = 34.1 em 34.1 em= *244.2 = (b) Absolute Density per ha Maple- 5\5=1 1*1221= 1221 maples per ha Birch- 1\5=.2.2*1221= birch per ha Beech- 2\5=.4.4"1221= beech per ha Locust- 1\5=.2.2"1221=244.21ocust per ha Basswood- 1\5=.2.2*1221=244.2 basswood per ha (d) Relative Density (RD) Maples- 15\20 = =75 Birch - 1\20 =.05"1 00=5 Beech- 2\20 =.1*100=10 Locust- 1\20 =.05*100=5 Basswood- 1\20 =.05*100=5 (e) Relative Frequency (RF) Maples- 5\10=.5*100 =50 Birch -1\10=.1*100 = 10 Beech- 2\10=.2"100 = 20 Locust -1\10=.1*100 = 10 Basswood -1\10=.1*100 = 10 (f) Relative Dominance (RB) Maples \ =.38*100 = 38 Birch \ = = 23 Beech \ * Locust- 7.57\ =.06*100 = 6 Basswood \ =.17*100 = 17 (g) Importance Value (IV) Maples = 163 Birch = 38 Beech = 46 Locust = 21 R~~!':wnnci f\ = ~? 0 (')

21 ... N TABLE 2. STATISTICAL RESULTS FOR SITE #2 Site 2 Total Distance= 62.49m D = Mean Distance 62.49m\20 = 3.12m D 2 = Mean Area 3.12m*3.12m = 9.76m 2 Total Density 10,000m2\9.76m 2 = trees per ha (a) Absolute Frequency Maple- 5 American Elm - 4 Basswood- 3 c) Basal Area Per ha Maple \11 = 9.81cm 9.81cm =.007.oor = 1.11 American Elm \6 = 24.51cm 24.51cm = * = Basswood \3 = 25.82cm 25.82cm = * = (b) Absolute Density per ha Maple- 5\5=1 * = maples per ha American Elm- 4\5=.8 * = American Elm per ha Basswood- 3\5=.6 * = Basswood per ha (d) Relative Density (RD) Maple -11\20 =.55*100 =55 American Elm- 6\20 =.3*100 = 30 Basswood - 3\20 =.15*1 00 = 15 (e) Relative Frequency (RF) Maple- 5\12 =.42*100 = 42 American Elm - 4\12 =.33*1 00 = 33 Basswood- 3\12 =.25"100 = 25 (f} Relative Dominance (RB) Maple -7.17\77.04 =.09*100 = 9 American Elm \77.04 =.5*100 =50 Basswood \77.04 =.41*100 = 41 (g) Importance Value (IV) Maple = 1 06 American Elm = 113 B::!sswood = 81

22 TABLE 3. STATISTICAL RESULTS FOR SITE #3 Site 3 (a) Absolute Frequency Total Distance = 71.38m Box Elder- 3 D = Mean Distance Maple m\20 = 3.57m Willow = Mean Area Grass m 3.57m = 12.74m 2 Beech- 2 Total Density Choke Cherry- 1 10,000~12.74~ = trees per ha c) Basal Area per ha Box Elder \4 = 36.58cm 36.58cm = = Maple = 54.8cm 54.8cm = * = Willow \1 = 101.9cm cm = = Grass- 0 not applicable {since nonwoody) Beech \2 = 13.73cm 13.73cm = = 4.4 Choke Cherry \2:;::: 23.1cm 23.1cm = = 6.59 (b) Absolute Density Per ha Box Elder- 3\5 =.6* :;: box elder per ha Maple - 1\5 = = maple per ha Willow- 1\5 =.2* = willow per ha Grass - not applicable Beech- 2\5 =.4* = beech per ha Choke Cherry- 115 =.2* = choke cherry per ha (d) Relative Density (RD) Box Elder =.2*100 = 20 Maple- 1120:;:.05*100 = 5 Willow- 1\20 =.05*100 = 5 Grass - 10\20 =.5"100 =50 Beech- 2\20:::::.1*100 = 10 Choke Cherry- 2\20 =.1*100 = 10 (e) Relative Frequency (RF) Box Elder - 3\12 = = 25 Maple =.os 100 = 8 Willow 1\12.08*100 = 8 Grass- 4\12 =.33"100 = 33 Beech - 2\12 = = 17 Choke Cherry- 2\12:::::.17*100 = 17 (f) Relative Dominance (RB) Box Elder \ =.18*100 = 18 Maple \ =.14*100 = 14 Willow \ =.64*100 = 64 Grass- 0\ = 0 Beech- 4.4\ =.02"100 = 2 Choke Cherry- 6.59\ = :: 2 (g) Importance Value (IV) Box Elder :: 63 Maple = 27 Willow = 77 Grass :;::: 83 Beech = 29 Choke Cherrv = 29 N