Ball moss aka air plants are distant relatives of the pineapple. They are extremely common wild plants here in Austin that grow just about anywhere there is shade. They can get as big as soccer balls.
When I first moved here people told me it was a parasite and that it killed trees. So much for local knowledge … Tillandsias are perfectly harmless. The only thing they take from a tree is a place to perch though sometimes they may decorate themselves with their landlord’s flowers. In the picture below spent crepe myrtle blossoms have become tangled in the leaves. I suppose a tree might be at some risk if there were enough Tillandisias to steal all the light and water but I think that if there are that many growing on a tree there is probably another issue or two involved.
Tillandisia make their own understated flowers. Their fruit promises to be useful for cancer and inflammation treatments and is under investigation.
Tillandisias are a bit like conjurers: making much of seemingly nothing at all. The grey ‘leaves’ have tiny scales that trap humidity — a reliable source of water as it sure does get humid here. The first time I stepped outside of the Austin airport it felt like the air was alive: it was that thick with water. As nitrogen-fixing plants they cooperate with bacteria to extract their food from the air, too. Even reproduction is effortless. Their seeds usually travel through the digestive systems of birds though they can be dispersed by the wind. Probably the bird method is superior since the seed is sort of painted on the tree bark and so less likely to fall off.
I love how their lives are so simple and easy. Compared to our complicated existence it is no wonder they look so alien!