While out walking, I glanced up into a palm tree (probably while looking for barn owls) and was surprised to find that both a fig and an oak had taken root in the upper portion of the palm. It made me laugh because both plants can be vigorous and tenacious in their distribution. But growing on a palm tree?!
I was curious how the plants could root along the palm trunk. While palm trees will host epiphytes (plants that use the host tree for support but don't take anything from the host) in more tropical areas, fig trees and oak trees aren't epiphytes. It turns out that the crevices on the palm tree trunk can accumulate organic material. If somehow a seed or acorn reaches there, perhaps deposited by a bird or squirrel, there can be just enough light, water, and organic matter to allow the plant to grow.
I can't imagine there is enough organic matter to support a healthy plant for long, but perhaps I'll go for another stroll past the palm tree soon to check on the plants' progress.