If you are familiar with Bromeliads, you know that among them are some of the most brilliant plants (not blossoms usually, but leaves) and yet some are very dull appear on trees as gray growing plants.
Bromeliaceae (the bromeliads) are a family of monocot flowering plants. Most species are native to tropical America with South America being the original location of these type plants. Of the approximately 3,170 species, other than those found mostly in the tropical Americas, there are a few species found in the American subtropics. There is also one species found in tropical west Africa, which is Pitcairnia feliciana.
Wikipedia adds this information:
" Pitcairnia feliciana is one of the basal families within the Poales and is unique because it is the only family within the order that has septal nectaries and inferior ovaries.  These inferior ovaries characterize the Bromelioideae, a subfamily of the Bromeliaceae. The family includes both epiphytes, such as Spanish moss (Tillandsia usneoides), and terrestrial species, such as the pineapple (Ananas comosus). Many bromeliads are able to store water in a structure formed by their tightly-overlapping leaf bases. However, the family is diverse enough to include the tank bromeliads, grey-leaved epiphytic Tillandsia species that gather water only from leaf structures called trichomes, and a large number of desert-dwelling succulents.
The largest bromeliad is Puya raimondii, which reaches 3–4 m tall in vegetative growth with a flower spike 9–10 m tall, and the smallest is probably Spanish moss".
Bromeliads include the gorgeous bright leaved plants called 'Bromeliads' which many grocery stores and the plant departments of the box stores and stores regularly sell. However Bromeliads include plants called epiphytes which some folks believe are parasites which will kill their trees. These are known as Spanish Moss and Ball Moss.
Here is what the Pinellas County Florida
Extension Agent online article says about
this question on June 3, 2008 (see http://plantingpinellas.blogspot.com/2008/06/spanish-moss-or-ball-moss-is-it-killing.html)
"Spanish Moss or Ball Moss - Is it killing my tree?
By Pam Brown, Urban Horticulture Extension Agent, Pinellas County Extension
In short, the answer is no to the question – “Is it killing my tree”? Spanish moss and ball moss are two of Florida's 16 native bromeliad species. Both are epiphytes, or air plants. Epiphytes can attach root structures to their host plant, but, they do not parasitize this plant; they simply use it for support. If air plants become so thick that they shade the leaves of the tree, growth could be slowed down. You usually see more air plants on weakened or damaged plants because they may also have thinner foliage. This allows more light into the branches, thus stimulating the growth of the air plants. So, air plants grow faster on stressed trees because the trees are weakened, but do not cause poor tree growth.
Spanish Moss (Tillandsia usneoides) is found hanging from tree limbs, especially live oak and cypress. It is gray when dry and light green when wet. It can hang down from tree branches in streamers up to 20 feet long. The small flowers are pale green or blue, and fragrant at night. Stems and leaves are slender and curly. Spanish moss has no roots; the leaves catch water and nutrients from moisture and dust in the air.
|Spanish Moss||Ball Moss|
Ball Moss (Tillandsia recurvata) is gray-green and found on tree branches
or telephone wires. It is often mistaken
for a small clump of Spanish moss. It grows
in clumps 6-10" in diameter on most
kinds of trees. Tiny seeds are blown by the
wind until they land on a tree branch. They
stick fast and develop root-like attachments
to the outside of the bark.
Ball moss is able to convert nitrogen in air into a form that plants can use like fertilizer. Except for beans and peas, most plants cannot do this. So, when ball moss falls to the ground and decomposes, it provides a little more fertilizer for other plants.
For more information about Spanish and Ball mosses, please access the UF/IFAS Extension publication Florida’s Native Bromeliads at: http://edis.ifas.ufl.edu/uw205.
Both photos are courtesy of Ed Gilman, Professor at University of Florida/IFAS
Here are two eArt Scans of Ball Moss created on December 17, 2011 by your PMNS Curator, Terrell William 'Terry' Proctor, J.D.
|Large Ball Moss||Small Ball Moss|
Therefore, enjoy these native epiphytes, Spanish and Ball Moss and don't worry about them killing your trees. They make the trees in much of the South look lovely and do no harm.