Odditrees
Trees are mysterious organisms and they live very different lives than we humans do. While scientists have come a long way in explaining what it is to be a tree, there are still many curious and astonishing questions about them that remain to be answered, and many more that have yet to be asked!
This page describes a couple of these "odditrees" that trees live with everyday:
Gift Giving
I'm sure you've heard someone pose the philosophical question "if a tree falls in the forest and no one is around to hear it, does it make a sound?" But have you ever wondered if a tree celebrates its birthday in a forest, whether the other trees give them a present? Well, it turns out trees don't celebrate birthdays, but they give each other gifts anyway!
In 1997, Suzanne Simard documented that vast, underground networks of mycorrhizal fungi connect up the roots of trees in a forest. What's more, she found that trees are able to exchange nutrients such as carbon through these connective fungal tissues. In return for access to the so called "Wood Wide Web," fungi receive sugars that their plants partners make through photosynthesis. This incredible mutualistic relationship between fungi and trees is estimated to have formed about 450 million years ago, but we are only just beginning to understand how it works and its significance for forest communities.
A few articles with more information on this fascinating discovery:
https://www.newyorker.com/tech/annals-of-technology/the-secrets-of-the-wood-wide-web
http://www.bbc.com/earth/story/20141111-plants-have-a-hidden-internet
https://www.ted.com/talks/suzanne_simard_how_trees_talk_to_each_other
https://e360.yale.edu/features/exploring_how_and_why_trees_talk_to_each_other
Raining Acorns
Hickories, Beeches, Spruce and Oaks all produce fruit that are a tasty staple for many a woodland creature - and maybe even a bit too tasty. While providing a substantial food supply to the animals around them is critical for the health of the entire ecosystem, the tree population itself can be jeopardized if too many of their fruits are eaten and not enough survive to germinate. To continue feeding the forest foragers without putting their survival on the line, trees have evolved a mechanism called masting.
Simply put, masting is when trees from a certain geographical area all produce a prodigious crop in the same year, known as a mast year. These mast years occur on somewhat regular cycles, taking place every 4 or 5 years for some tree species and 8 or 9 for others. During a mast year, the critters that munch their way through the crop yields of regular years aren't able to consume the copious amount of fruit that each tree in the puts out. If only one tree had an unusually large crop, then maybe they would be able to gobble the lot, but because the trees are co-ordinated even the greediest, most voracious animals cannot each all the fruits.
So why trees do this seems pretty clear, but at the moment how they co-ordinate across such long distances, and over lengthly and variable time frames remains somewhat of a mystery. One hypothesis is that weather - namely high rainfall in the year before and elevated spring temperatures - could serve as a signal to all the trees in a certain area to prepare for a mast year. However, this idea fails to address how different tree species have different masting cycles, how the length of these cycles have been able to remain relatively consistent during climate fluctuations, and how trees are able to mast synchronously across distances greater than the range of typical weather systems. Clearly, much more information remains to be uncovered before the mysterious masting phenomenon can be fully explained.
Articles & videos with a bit more on masting:
https://www.washingtonpost.com/science/must-be-a-mast-year
https://www.youtube.com/watch?v=EQ748TZcuqs
https://www.outdoors.org/articles/amc-outdoors/mystery-mast-year