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Saturday - March 12, 2011

From: San Marcos, TX
Region: Southwest
Topic: Herbs/Forbs, Trees
Title: What are the grey-green plants on oak trees in San Marcos, TX?
Answered by: Barbara Medford


The oak trees in the neighborhood in San Marcos, TX, are covered with clumps, or balls, of gray/green fluffy-looking plants. they remind me of bromeliads. You can pull and knock them off; after wind and rain, they fall to the ground. Right now, there are little or no buds on the trees, especially the limbs that have lots of these 'bromeliads' - the branches look dead. Are these plants parasites? Are they killing the oak trees?


From a previous Mr. Smarty Plants answer, we believe that what you are seeing is Tillandsia recurvata (Small ball moss). This is an epiphyte or "air plant," not a parasite. It draws no nutrition from the tree, just uses it as a place to live. They are often seen on oaks, and are native to Texas and a few other states. Sometimes people think they are killing the oaks because they tend to grow on interior, old limbs, where they can get more shade. Here are some pictures and information from the University of Texas Image Archive of Central Texas Plants. They can be unsightly but do no harm. We have heard of people using them to make Christmas decorations.

You were correct in saying they look like bromeliads; they are, in fact, members of the bromeliad family.

From our Native Plant Image Gallery:

Tillandsia recurvata

Tillandsia recurvata




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