Wyoming Spring Creek – Forest Regeneration Near Fallen Trees

I chose to do an ecology-based independent project. For my question, I asked “Does proximity to large piles of coarse woody debris affect the overall species diversity in regenerating forest by way of light availability, browsing by ungulates, and/or space availability”? I then hypothesized that areas nearer to coarse woody debris will have more diverse and rich sapling environments due to higher light availability and decreased ungulate browsing.

In order to test my hypothesis, I collected some data from a coniferous montane forest that had experienced a lot of deadfall due to pine beetle outbreaks and fire. I collected data for 2 day wherein each day I set up 10 plots for a total of 20 plots. For my research, I had two kinds of plots. My “A” plots were proximal plots in that they were set up within a <5 m radius from an aggregation of deadwood. I defined deadwood or coarse woody debris (CWD) as anything that was a full fallen tree or larger, so fallen branches were not counted as CWD. My “B” plots were my controls. They were plots that were distant from CWD. Originally, I had planned to make them plots that were 30 m away from my A plots, but due to the nature of my field conditions that was not possible because there was too much CWD. Instead, my “B” plots were 10-20 m away from my “A” plots. Each plot was 3×3 m.

Once I had my plots measured and outlined in flags, I took the diameter at breast height (DBH = ~4.5 ft in height) of all woody plants that were taller than 20 cm in my plot (trees or shrubs). If the plant was not high enough for DBH, I measured it at about 10 cm. This will allow me to calculate the approximate biomass of woody species in my plots. I then identified the species of woody plants within my plot so that I can calculate species diversity and richness. Higher diversity often correlates with better forest regeneration. I also measured the amount of light that was hitting each plot at the center in order to look at relative canopy cover and gap size. Gaps are created in the tree canopy when a large tree falls down which lets more light in. That fallen tree then becomes coarse woody debris. Additionally, I performed scat surveys within my plots in order to look at browsing (plant consumption) rates by ungulates (moose, deer, elk, etc.). Heavy browsing can limit forest regeneration, so it is an important factor in my question. In my field notes, I was sure to describe the kind and relative amount of CWD at my “A” sites. I also did some plot description in terms of percent vegetation cover so that I would have a better idea of the whole picture when analyzing my data trends.

Overall, my first time of running my own field project was pretty fun. I learned a lot about setting up a project and then actually performing it in the field. I would probably change a lot if I were to repeat the process, but it was a really goof learning experience. I can’t wait to try again in the future with this experience already under my belt. Even if I don’t get the results I thought I would, I’m happy I got to try it out anyway, plus that’s ecology (or science in general) for you!

More later,


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