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Hanging
Moss & Ball Moss
Spanish Moss (Tillandsia usneoides) is
an epiphytic plant taking nothing from its host. (epiphyte - plant
that grows not in the soil but on another plant, depending on it
only for physical support; an epiphyte makes its own food, thus
differing from a PARASITE. Epiphytes obtain moisture from the air
or moisture-laden pockets of the host plant.) If it gets so thick
that it prevents sunlight from reaching the leaves and buds of its
host it can cause degradation to that host but this and physical
weight are the only ways it can damage the plants. It is most
commonly spread from one plant to another by pieces of the plant
being physically moved by birds, animals or wind storms and by
seed. While any of many copper based fungicides or herbicides will
kill Spanish Moss, I know of nothing that can be sprayed on plants
to prevent its growth before it is established. Mechanical control
by removal is an alternative, but very labor intensive. See the
following for more information on Spanish Moss:
Spanish Moss Plant (Tillandsia
usneoides): This long, whisker-like plant growth hangs from trees
in Southeast and East Texas. It is an epiphyte. It grows on
hardwoods and conifers along rivers and creeks in the more humid
areas of Texas. It is a member of the pineapple family (Bromeliaceae).
It has been reported to kill trees where development is extensive.
This seldom occurs. It can be removed using mechanical means where
growth becomes thick enough to cause tree damage. Chemical
treatments are not recommended.
Spanish Moss and Ball Moss by Nancy P. Arny
Spanish moss (Tillandsia usneoides) and ball
moss (T. recurvata) are common elements of the Florida landscape.
They are two of Florida's native members of the Bromeliaceae, also
known as the pineapple family. This family includes species as
diverse as pineapples, Spanish moss and a carnivorous relative
native to Australia. Bromeliads are members of the plant division
Magnoliophyta-the flowering plants. While most Floridians are at
least vaguely familiar with Spanish moss, many have never seen it
flower and may be surprised at the beauty of its delicate blossom.
Of course, the fact that both Spanish moss and ball moss produce
flowers is proof that they are not truly mosses at all.
This fact sheet will help the reader to distinguish between the
two common Tillandsias. It also provides basic information on the
biology and ecology of these fascinating plants and provides
recommendations for their management in the home landscape.
Bromeliads Like almost all members of the Bromeliaceae, Spanish
moss and ball moss are perennial herbs. This means they do not
have permanent woody stems above ground, but that individual
plants persist for years and will reproduce without human
intervention. Like many other bromeliads, these plants are
epiphytes or "air plants". This indicates that they do not require
soil to root in, but can survive and thrive growing above the
ground hanging on branches of trees or other structures. They are
not parasites. Without soil as a source of nutrients, these plants
have evolved the capacity to make use of minerals dissolved in the
water which flows across leaves and down branches.
Spanish moss plants appear to vary in mineral content and it has
been proven that they gain a significant portion of their
nutrients from stem run-off from the trees on which they are
anchored. The native ranges of Spanish moss and ball moss include
the entire state of Florida. Ball moss can be found along the
margins of new world continents from the southern U.S. to central
Argentina. Spanish moss grows as far north as Virginia. It is
believed to have evolved in the Peruvian Andes and can be found
growing as far south as Argentina and Chile. This gives it the
broadest natural geographic range of any bromeliad.
Tillandsia Biology
The genus Tillandsia is one of three sub-families of the
Bromeliaceae family. The leaves of all Tillandsias are entire-they
have no spines on the edges of the leaves. There are some 500
recognized species of Tillandsia, as well as many cultivated
hybrids. All these species have scales on their leaves. These
scales, also known as trichomes, help the plant to capture and
conserve water and are critical to their survival in most
climates. Under natural conditions, moisture content of the
atmosphere surrounding Spanish moss and ball moss varies greatly.
Rather than absorbing water through roots, they absorb moisture
through the scales of the leaves. These scales act as pumps,
drawing moisture from the outside of the plant into its interior,
allowing the capture of water and the minerals dissolved in it.
While both species will grow on wires, fences and other non-living
structures, they are particularly well adapted to growth on trees.
There is some evidence that Spanish moss grows better on dead
trees than on live ones. This may be due to its preference for
well lighted, but moist habitats. Research on ball moss conducted
in Argentina, indicated that it can cause significant shade
competition and limb breakage when present in great numbers on
host trees. Heavy infestations of Spanish moss may lead to the
same results, but before homeowners rush out to eradicate these
picturesque plants from their trees, they should recognize the
ecological significance of these "epiphytic weeds".
Spanish moss which prefers well lighted but moist habitats, is
commonly found near rivers, ponds and lakes. It will also grow
away from wetlands if humidity is fairly high. It is found on both
broadleaf and needle-leaf trees, deciduous trees and evergreens.
It is common in Florida on hackberry and live oak trees, since
these trees have more nearly horizontal branches than many other
species. Characteristics of preferred host trees include:
significant branching, resulting in many forks; rough bark with
fissures or scales to capture and hold seeds or fragments of stem;
thick permanent (nonexfoliating) bark; lack of allelopathic
substances. The latter factor is the reason camphor trees appear
to resist infestation. Many tropical trees release chemicals which
make conditions unfavorable for growth of young Tillandsias.
Greener plants are indicative of a healthier environment. Festoons
of gray Spanish moss may not be healthy or may be suffering from
moisture stress or other environmental factors. A careful
inspection of a heavy festoon of moss will reveal that individual
plants are usually only 15 to 20 centimeters in length. While
plants do occasionally reach lengths of 45 centimeters, the
apparent length is the result of numerous plants overlapping each
other. The living portion is that which is covered by the
grey-green scales which superficially resemble foam-rubber. Dead
portions of the plant look like black horsehair. Like horsehair,
they were once used to stuff furniture and automobile seats. The
"hair' is actually a primitive vascular system.
A single strand of Spanish moss, laid on a flat surface, will
reveal its scorpoid dichotomous growth pattern. This pattern is
the result of alternate branching of the plant at each growth
point or node. The plant forks at each node. At the first, the
branch on one side will elongate and a few short leaves will
appear. At the next node, the opposite branch will elongate,
resulting in a zigzagging pattern. The length of the distance
between nodes appears to be an indicator of the plants' response
to its habitat.
The plant reproduces both by seeds and by vegetative growth. When
small pieces of the plant are broken off and moved (usually by
wind or animals) to another appropriate growth site, they will
begin to grow into new plants. Dissemination of Spanish moss
through vegetative reproduction is greatly accelerated by violent
storms. Seeds appear to disperse between December and March. While
little is known about conditions necessary for germination, the
seeds do germinate and become fixed to their new growth site after
being distributed by the wind. Small non-absorbing root-like
hold-fasts help the seed to anchor, but quickly dry up as the
plant grows at its terminal end and dies back at its root end.
Flowers appear in spring on the terminal ends of Spanish moss
strands. Flowers in most bromeliads are terminal. They may appear
to be on side strands, but once a strand flowers, a new branch is
formed at the node above, sending growth responses along an
alternate path which had only supported a simple leaf. Flowers
blossom in April in Florida, usually a single flower on each
plant. The yellow-green blossoms are relatively inconspicuous, but
have a pleasant, subtle fragrance when many are massed together.
Flowers last about four days and are followed by development of a
seed capsule. These capsules open the following December or
January, releasing 2 to 23 seeds. Each seed has a mass of hairs
which function as a parachute. The hairs are covered with tiny
barbs, enabling the seed to catch and anchor on appropriate
substrates.
Ball moss exhibits many of the same Tillandsia characteristics,
including absorbing scales and entire margins. Unlike the pendent
Spanish moss, however, ball moss exhibits a highly compact growth
form. The stiff, narrow, pointed, green-grey leaves arise from the
central mass of the plant curving outward. They are covered with
trichomes; which give the plant a somewhat spongy appearance.
Individual plants generally measure between 15 and 18 centimeters
in diameter, although larger masses of multiple plants are
frequently encountered.
Ball moss flowers are a more conspicuous blue-to violet. They
appear in spring on a long stem emerging from the central mass of
the "ball" of leaves. Examination of "balls" which have fallen to
the ground will often provide an opportunity to see the seed
capsule. Like seeds of Spanish moss, these seeds are
wind-dispersed. The structure of ball moss is a compact mass of
stiff leaves arising from a central core.
Ecological Relationships
Both Tillandsias, as mentioned above, are part of the image of
Florida. Masses of ball moss, like beads on a giant necklace, can
be seen on telephone wires stretched across streets and highways
in southern Florida where the humidity allows survival in such
exposed areas. Spanish moss, on live and dead trees and fences is
part of the image of the South. Although the ecological
significance of ball moss is still to be examined, Spanish moss
serves a variety of ecological roles.
Many animals use Spanish moss for protection, taking cover in
thick masses of pendent strands. Many insects and other
invertebrates hide in moss masses, making it an unlikely choice
for bedding by campers. The prevalence of "red bugs" or chiggers
in the plant is legendary. Spiders, thrips, and dozens of other
insects hide in the moss as well. This abundance of invertebrates
may or may not be the reason that at least two species of bats
also use festoons of Spanish moss for cover. Both red bats and
pipistrelles use masses of Spanish moss as day-time resting sites.
Spanish moss is also a significant component of the nests of
several species of birds: namely the parula warbler (Parula
Americana) and the Baltimore oriole (Icterus galbula). While many
other species of birds may use strands of moss in their nest
building, when these two species nest in the Southeast, Spanish
moss is the major constituent of nests, being woven into hanging
sacs to hold eggs and young.
Ball moss has not been studied as intensively as Spanish moss and
so evidence of its ecological significance is lacking. Still, it
represents another strand in the web of life, contributing to
biological diversity. In South America, concerns have been raised
about its negative effects on many forest and urban trees. There
is no doubt that heavily laden branches do shade lower vegetation
and intercept light needed for photosynthesis. Also, branch
breakage does occur. Fortunately, such heavy infestations are not
too common in Florida.
Management
Chemical control of Tillandsia is possible. As
of 1996, the following materials are licensed for control of
Spanish moss and/or ball moss: TC Tribasic Copper Sulphate, Blue
Shield, Basic Copper 53, Micro Flo Basic Copper 53, Micro Flo
Copper 3 FL. It should be noted that there is evidence that
copper-based herbicides and fungicides may cause damage to tender
growth on oak trees. As with all herbicides, when using these
materials read and follow label directions carefully.
Hand removal of Spanish moss is possible and
can be done successfully on small trees by standing on a ladder or
using a pole. For larger trees, a basket-truck or "cherry-picker"
is usually necessary. The procedure is labor intensive and costly.
Homeowners would be well advised to consider the ecological
benefits of Spanish moss and let the plant grow unless heavy
infestation is endangering the health of the tree through reduced
light. In such cases, hand removal of the denser festoons coupled
with judicious pruning of light-suppressed branches will usually
restore the tree to a more attractive and healthier condition.
Hand removal of ball moss is possible as well. Use caution, as
tearing out of firmly attached clumps may damage twigs, opening
the way for secondary infection by fungi or insects.
To obtain a deeper understanding of these plants and their
relatives, consult Tillandsia: The World's Most Unusual Air Plants
by Paul Isley III, published by The Botanical Press, 1987.
1.This document is FOR 52, one of a series of the School of Forest
Resources and Conservation, Florida Cooperative Extension Service,
Institute of Food and Agricultural Sciences, University of
Florida. Publication date: October, 1996.
2.Nancy P. Amy, associate professor, School of Forest Resources
and Conservation, Cooperative Extension Service, Institute of Food
and Agricultural Sciences, University of Florida, Gainesville,
32611.
The use of trade names in this publication is solely for the
purpose of providing specific information. It is not a guarantee
or warranty of the products named, and does not signify that they
are approved to the exclusion of others of suitable composition.
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