Students in general ecology (EES-152) resurveyed a portion of the Lehigh Experimental Forest, to assess changes in tree growth, mortality, and recruitment since 2013. No new trees greater than 1.4 m high were documented, and both growth and mortality varied considerably among species. Over 500 trees were measured, and the plot above shows data for the dominant trees (those with >15 individuals included in the survey).
We will use these data as a springboard for discussion of processes controlling forest dynamics, and will examine some of these issues in greater depth during our discussions and future lab activities.
For now, students should answer the following questions:
1. The dbh measurements were converted into estimates of area, assuming that each tree was a perfect circle in cross-section. Why do you think basal area was used to compare growth among the different species? Why was this expressed as the average change in basal area per tree, as opposed to the total change in basal area for all individuals of the species? What factors might have caused the observed differences in radial growth among species?
2. What does the pattern of mortality and recruitment suggest about the future of the Lehigh Experimental Forest? What factors might have caused the differences in mortality among species during these two years? What factors might be contributing to the lack of new tree recruitment in the forest?
3. Which species had both very high mortality and very low growth during this time period? Do some research on current threats to this particular species, and summarize your research in a short paragraph.
More data from the Lehigh Experimental Forest camera traps. Our complete list of “trapped” species since October now includes:
- Buteo jamaicensis (Red-tailed hawk)
- Canis lupus familiaris (Domestic dog)
- Felis catus (Domestic cat)
- Homo sapiens (Human)
- Marmota monax (groundhog)
- Meleagris gallopavo (wild turkey)
- Odocoileus virginianus (White-tailed deer)
- Procyon lotor (Raccoon)
- Sciurus carolinensis (Gray squirrel)
- Sylvilagus floridanus (Eastern cottontail)
- Tamias striatus (Eastern chipmunk)
- Turdus migratorius (American Robin)
- Vulpes vulpes (Red fox)
A few highlights from the two video cameras (wild turkey at the end!):
Nice article Michelle. Too bad the paper didn’t publish it. The site has historical significance and is a great outdoor laboratory for students.
Originally posted on In the Forgotten Forest:
Although I submitted this article to Lehigh’s student newspaper a few months ago, The Brown and White, it never got published (in the paper or online) for unbeknownst reasons. It refers to the upcoming plans to renovate Williams Hall, and my concerns for the future fascinating and historical forest directly adjacent to the building.
The recently drafted Campus Master Plan lays out the administrative vision for future improvements to Lehigh’s Campus. (Check out the whole plan at https://www.lehigh.edu/~inspig/lu_cmp_book_10-4-12.pdf). I had the opportunity a few weeks ago to attend a graduate student senate meeting focused on aspects of this plan, and was very troubled by the idea to re-landscape the area behind Williams Hall (the building behind Linderman Library that housed Earth and Environmental Sciences before STEPS was built) to allow more pedestrian access. Although plans have not been implemented yet, I worry that the ecological, historical, and educational significance…
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