Crow, Daijah, Preston

Group Roles

Crow Visual Director

Daijah Editor

Preston Documenter

Forbes does it affect how grass grows?

Background Information

For our prairie experiment we measured the Indian native grass in each kind of plot to see if the amount of forbes affects how tall the grass grows. Our theory was that if there were more forbes there would be more root crowding, causing the plants to not grow to their potential length. Plants with deep root systems are more successful and have come to dominate the prairie landscape.

The Free State Prairie is a tall grass prairie was an experiment developed through a collaboration between Free State Highschool and KU. The prairie is available to high school and university students, teachers, and most of the Lawrence community. They have all worked together to design, create, and maintain both the experiment and the demonstration garden at Lawrence Free State High School. The Prairie is an accessible, outdoor educational and research resource. Students are restoring the local, native biodiversity of the tall grass prairie ecosystem.

Basically, the project leaders Julie Schwarting and Dr. Helen Alexander decided to plant prairie grass seed over the entire site, and then divide the area into 18 plots, with six replicates of each of three treatments. One treatment was the grass-only treatment, the other two treatments were Prairie grasses + 1x forbes & Prairie grasses + 2x forbes. So in conclusion, our goal during this experiment was to see that if there were more forbs and grasses in a plot, would there be over population causing the roots not to grow properly making the grasses shorter.

Data Collection Methods

We used a 2 meter stick to collect our data. So before we went into a new plot we looked to find the tallest grasses. Then we would go measure them and compare the heights of them and use the tallest in our data. We repeated this until we had all the data we needed.

Conclusions

While taking measurements in the plots, we were looking to see how tall the Indian native grass was in the 3 different kinds of plots. Our question was if the amount of seeds in both forbes and grass, will affect the height the grass reaches. When we were gathering the heights of the tallest grass in each plot we were looking at averaging the lengths later. When averaging we found that the prairie plots with no forbes had the longest pieces of native indian grass. The plots with 1x forbs & grasses averaged a length of 99 inches, the 2x forbes & grasses averaged 105.3 inches. Our winner (only grasses) averaged 106 inches.

There were some flaws in our experiment though. The first being that the grasses still have time to grow so there is no way of knowing if those strands of grass are going to grow anymore. There was also no pattern in the data we collected. If we could do this again, i think we would need to talk through all the possible potholes in our experiment, or we could go on the trial and error route.

Things to change for the future

The one and only inaccuracy that could have happened is that if the grass was not straight up when measuring so we held up the grass to make it more accurate. We measured 3 of each kind of plot. One thing that we could have done is make sure we did the same kind of grass but they all looked the same. The other question is that if you wanted to compare grasses to see what is the tallest then compare that grass for the experiment. I think there is always more you can do in an experiment but time can make it hard or just not thinking of it till after.

Our Data

Sources

The book we used is the field guide to the common grasses of Kansas, Nebraska, and Oklahoma.