Deborah Thompson-Rigby and Dr. Zachary Aanderud, Plant and Wildlife Sciences
Learning how to conduct research is vital if one plans to continue doing research past their undergraduate degree. In the near future I will be starting a masters degree where I will really learn the ins and outs of research, but the preparation needed to get results in research is more daunting than it looks from the outside.
Bullhog mastication is becoming a common practice all over Utah to control the encroachment of piñon and juniper trees on Utah rangelands. When these trees take over a given area, the undergrowth gradually dies and the piñon and juniper trees eventually densely populate the area. They become a wildfire threat since they are large and grow close together causing hot crown fires. In order to avoid these dangerous large fires, land managers throughout the state have been using this bullhog practice to shred the trees, reducing the fire fuels and bringing the fuels and fire closer to the ground. That way if a fire does come through, it will be a ground fire instead of a crown fire, which is much easier to control. Yet little is known about what happens to the bullhog chips and microbial activity in the soil around these chips. My eventual goal will be to understand the changes in time of the soil composition and microbial activity that takes place under shredded sites ranging from the oldest to newest areas. But in order to understand these things about the soil, I needed to learn the preliminary of how to do research and the processes of site selection and soil DNA analysis.
The process of site selection turned out to be more difficult than expected since I have never done anything like this before in my life. The site selection process has involved contacting every Bureau of Land Management (BLM), Forest Service (FS) and Division of Wildlife Resources (DWR) office and land manager in Utah to find all their available bullhog sites ranging from the year 2003-present. We originally hoped that we would be able to obtain shapefiles from the land managers and on ArcMap randomly select sites throughout the state that met our criteria. We need a total of 40 sites and luckily I took a GIS class last semester which taught me how to use NAIP imagery and ArcMap and so I was able to use these newly acquired skills in analyzing our imagery. But after trying this method with a nearby site we learned that this would not work due to differences in bullhog techniques throughout the state. Instead we needed to meet individually with each land manager in order to ask them questions and have them show us their sites. So far we have met with 5 different land managers and seen over 30 sites. At least 20 of those sites fit our criteria, so I will now be able to use the shapefiles of those sites that we have seen and randomly select sites on ArcMap where we can sample soils. I have gained valuable networking connections and learned techniques that could be very useful if I chose to work for one of these agencies in the future.
Figure 1- A large Bullhog and the before and after of the piñon and juniper trees
The soil was the next section of interest for us and in the future will be sampled in several areas beneath and around the chips. In order to prepare for massive sampling and testing we have been trying to work out the kinks in our DNA lab work. Using laboratory soil, we used a MOBIO Powermax isolation kit to do DNA extractions from the soil, learning how to isolate pure DNA. After isolating the DNA we used a Nanodrop Spectrophotometer to quantify and find the purity of DNA. For the most part our results were good, but many times our gels would have crooked or extra bands. I suggested that we try different amounts of DNA and dyes, voltages and locations on the gel wells to get better results. We researched online and tried switching our voltage from 90 V to 80 V and ran our samples in different amounts and locations on the gel. We found that the slower voltage was better, that our original sample amount was fine, and that samples should not be run on the side wells. We also found that the extra bands in the gels which were not identifiable before were extra DNTP’s and whole genomic DNA. We found through research that gels can be run at an even slower voltage than 80 V and run overnight and we are curious to try this in the future. In the process of learning these more complex procedures I have learned and refined essential lab techniques like how to better use pipettes, centrifuges and sterile lab techniques. Learning these methods has prepped me for learning more techniques like cloning and quantitative PCR which will help us in determining the microbial activity that is occurring in the soil and under these bullhog chips.
This is just the beginning of a large project, but it has been a great starting point for me in order to learn the amount of work and time that goes into figuring out how to do research. Learning which procedures to use through trial and error has been a main factor in setting up this project. This project requires much more time and research but will eventually result in a Masters thesis and hopefully two scientific journal articles in a soil or rangeland journal.