Plants and the Soil They Grow In

Background and Purpose
We know that soil greatly affects the plants (growth rate, health, etc.) that grow in it. Moisture affects the types of soil/plants that grow in it because some soil holds more moisture. Most plants grow well in loamy soil. It is hard to grow plants in sandy soil. It is important so gardeners can know what kind of soil to buy for certain plants. If we know more about soil types that plants grow in, then we can conserve our rare plants more efficiently, and also farmers can use the right soil to help the crops that are planted to grow faster.

This issue is relevant to watershed health because by knowing how fertile different types of soil are we can use the right amount of fertilizer with minimal amounts of runoff during rains. Without knowing the soil fertility level there could be extra fertilizer going into lakes.

We looked at different types of soil at different locations and the plants around them. Our question is how do different types of soil react to different plant communities. We predict that we will find more different species of plants in the prairie than in the woods.

Methods
We chose to sample soil from two different environments: forest and prairie. We randomly chose two core samples from each environment. We split each core sample into thirds. We took the top third and put it into the odd numbered bags of the right location and put the bottom third into the even numbered bags. We threw the middle third of each core sample away. Then we tested a top and bottom 3rd of each location with a key to soil texture by feel and took one ¼ meter2 quadrat sample for each core sample site. We recorded the number of different species and the number of individuals of each species, and then we identified and pressed a sample of each species of plants that was in the sample quadrat. We did this once for each core sample site.


Paul and Anthony sampling plants in woodland site


Results
We found 11 different species of plants; 6 in the prairie and 5 in the woods. There was more species of plants in the prairie than in the woods. When we tested the soil, we found that the prairie has silt loam and silty clay loam type soils; we also found that the woods has loam and silt loam type soils.

List of plants found at both sampling sites
#1 Plant - LAMIACEAE Monarda fistulosa "Wild Bergamot"
It is a green prairie plant with thick stem and long serrated leaves. There is also a single main vein going up center of every leaf.

#2 Plant - POACEUE Sorghastum nutans "Indian grass"
Green prairie plant that is three to five feet tall. It has green and brown seed/flower pods.

#3 Plant - SCROPHULARIACEAE Veronicastrum verginicum "Culvers Root"
Green prairie plant with a flat stem and serrated leaves. Leaves in sets of four in whorls.

#4 Plant - SPIDERWORT Tradescantia ohiensis "Spiderwort"
Green flowering prairie plant, purple flowers with thick buds. Long thin leaves that go to a point; a short plant overall 10-20 in.

#5 Plant - Marsh marigold?
Small green prairie plant about 10 inches high with one chordate and serrated leaf on the end about 2 in. wide and 3.5 in. long.

#6 Plant - Nettles?
A green prairie plant with compound leaves in sets of fives. It has thorns on stem and serrated leaves.

#7 plant
This plant is green and comes from woodland. The leaves are a little white on the under sides; it has compound, serrated leaves and the stem has thorns on it.

#8 plant
This plant is green and comes from woodland. It is a little furry under the leaf and has simple leaves and does not have many veins. Veins are branching towards the leaf tip. The leaves are smooth on the sides. The petiole is reddish in color.

#9 plant
This plant is green and comes from the woodland. The leaves are simple and serrated. The veins are in sets of three and are thick.

#10 plant
This plant is green and comes from the woodland. The leaves are simple and indented roundly on the side. The stem is thin and weak.

#11 plant
This plant is green and comes from the woodland. The leaves are big and simple. The leaves are furry on the underside. It has alternate veins that grow towards the sides.



Poster showing plants collected at two sampling sites.

Discussion and Conclusions
Our hypothesis is that we have more plants in the prairie because the prairie has more different subcategories of soil. There are more different types of soil in the prairie because the prairie is not on a slope and water doesn’t go through and take the lighter soils into the lake. In the woods the land slopes towards the lake so the water takes the lighter soils into the lake; also the woods do not have enough vegetation to hold the soil there so there is more erosion. Another explanation for finding more plants in the prairie is that all the plants get more light, water, etc., while in the woods the trees shade the other plants. We feel confident about our soil hypothesis but we wish we had taken more soil data.

Some questions that came up are what would happen if the slope were on the prairie instead of the woodlands? What would happen if we took away the vegetation from the prairie or the woodland and used different slope combinations? We would be very interested in an experiment to answer these questions. If we did this experiment again we would collect more data and maybe test different places. To best manage watershed health, we would use vegetation to avoid erosion.

References
Paul’s brain
Anthony’s brain
Juan’s brain
Robin’s brain
Jim, Kari and Angela’s brains
Knopf. The Audubon Society Field Guide to North American Wildflowers
Ladd. Tallgrass Prairie Wildflowers. 1995
Tekiela, Stan. Wildflowers of Wisconsin 2000