Sources:
https://www.treesandshrubsonline.org/articles/abies/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6268138/
https://ncchristmastrees.com/fraser-fir-trees/
https://cnr.ncsu.edu/news/2021/12/christmas-trees-smell-good/
https://www.conifers.org/pi/Abies_procera.php
https://andrewcfox.wixsite.com/andrewcfox/post/totw-fir
https://andrewcfox.wixsite.com/andrewcfox/post/tree-of-the-week-the-trojan-horse
https://www.rbth.com/history/335727-charlotte-prussia-christmas-russia
https://www.whitehousehistory.org/press-room/press-backgrounders/white-house-christmas-trees
https://www.nps.gov/whho/learn/historyculture/national-christmas-tree-history.htm
https://northernwoodlands.org/articles/article/blisters
https://onlinelibrary.wiley.com/doi/full/10.1002/adsu.202200234