Aerial Image of the study site. Photo provide by Dr. Eben Broadbent.
The Cone Park Compost Project
The Reisinger Lab is partnering with the City of Gainesville to test alternative management practices for multipurpose fields in city parks. This project was initiated in February 2019 and is intended to test the effectiveness of topdressing a multipurpose field with compost as an alternative to fertilizer applications. We are measuring a wide variety of metrics for this project including soil chemistry and organic matter, soil nutrient leaching, turfgrass quality, and aerial assessments of various soil and plant parameters using drone flyovers and hyperspectral imagery.
The Reisinger Lab is partnering with the City of Gainesville to test alternative management practices for multipurpose fields in city parks. This project was initiated in February 2019 and is intended to test the effectiveness of topdressing a multipurpose field with compost as an alternative to fertilizer applications. We are measuring a wide variety of metrics for this project including soil chemistry and organic matter, soil nutrient leaching, turfgrass quality, and aerial assessments of various soil and plant parameters using drone flyovers and hyperspectral imagery.
Pre-application
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In March 2019, we completed pre-treatment soil sampling to document soil chemistry and organic matter content across the field. We also completed a drone flight to take aerial photos. Finally, we organized a community scientist training and data collection day to assess the relative cover of grasses, weeds, and bare soil at each plot.
The soil chemistry data from this pre-application period told us that there were some differences in soil nutrient concentrations across our different treatments. Using this information will allow us to compare the change in soil chemistry in response to specific treatments, rather than confusing a treatment (fertilizer/compost) effect for background variation. 
Marking the perimeter of the grid that will be used throughout the experiment.
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Aerial image of the sampling grid laid out on the multi-purpose field at Cone Park. This image was taken prior to compost or fertilizer application. The grid lines separate different plots that represent statistical replicates for our study.
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Compost application
After collecting our preliminary data, and waiting for the weather to warm up a bit, we were able to apply our compost and fertilizer treatments to the field in early April, 2019.
Aerating the soil prior to compost application allows materials applied on the surface to penetrate deeper into the soil profile.
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The first step of the process is to aerate the soil. The machine in the picture on the left pulls ~6" deep plugs out of the soil, allowing air to penetrate deeper into the soil profile. This also allows any material applied on the soil surface (such as compost or fertilizer) to make it into the rooting zone more rapidly. |
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Next the compost is 'topdressed' onto the soil (spread on top of the soil). The aeration process insures that this compost reaches the rooting zone. After the compost is spread, it should be 'watered in' with a short irrigation cycle. Compost or fertilizer should NEVER be applied prior to expected storms, which will cause the material (and nutrients associated with it) to runoff the landscape into surface waters, causing water quality issues. Watering in the compost (or fertilizers) will insure that the material penetrates into the soil and minimize volatilization of ammonia and other gaseous compounds. In addition to compost, some plots received fertilizer applications (1lb N / 1000ft^2). Some plots received both fertilizer and compost, and some received neither. We will compare these four different treatments to see how effective the various combinations are for improving soil health and landscape quality. |
Compost was topdressed onto the field, with some plots receiving compost and some not.
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Post application
Aerial image of the experimental park following compost and fertilizer applications. This image was taken ~3 weeks after treatments were applied. You can already begin to tell differences in treatments, as certain rows or columns are visually more green than others.
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In early May, 2019, we performed our post-application sampling for aerial imagery, soil chemistry, and nutrient leaching rates. As you can tell from the aerial image, there were some immediate, and obvious, differences in plant quality, with certain plots being 'greener' than others. We are going to keep the treatments a secret for now, but feel free to guess what's causing those dark green rows and less dark, but still a little green, columns.
We have collected and are beginning to analyze nutrient leaching data from each plot. Leaching rates were estimated using a new rapid core leaching experimental approach. This approach allows us to rapidly estimate leaching rates from multiple sites in a single day, but is not directly applicable to real-world rates. We are working to calibrate our rapid core leaching rates to real-world rates using a lysimeter study linked with this core leaching approach. 
Hallie (left) and Daniela (center) performing a rapid soil core leaching test at the Cone Park multipurpose field.
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