By: William M. Johnson
Spanish moss has been called both picturesque and
spooky, but whatever you think of it, Spanish moss
draping live oaks and bald cypress contributes a lot to
the look of some southern landscapes.
Spanish moss (Tillandsia usneoides) is a flowering,
epiphytic plant belonging to the bromeliad family.
This makes it related to the plant that produces pineapples,
which also is a bromeliad.
Widely distributed along the coastal strip of the
southeastern United States from southern Virginia to
eastern Texas, Spanish moss occurs across coastal
areas of Texas. But, oddly enough, it can be either
very common or very rare depending on the location.
I frequently receive questions from people who
are concerned that Spanish moss is damaging their
trees. Contrary to what many people believe, Spanish
moss is not a parasite and does not injure a tree by
obtaining any nourishment from it.
As an epiphyte, Spanish moss lives on the tree but
is independent of it. It uses the tree only for support
and does not invade the living tissue like mistletoe
and other parasitic plants.
Spanish moss gets everything it needs from light,
rainwater and air. Like other green plants, Spanish
moss uses light in a process called photosynthesis to
create its food from carbon dioxide and water. Dust in
the air also supplies some needed mineral nutrients.
Spanish moss has the ability to absorb quantities of
moisture into its leaves when it rains. The gray scales
that cover the leaves and give this plant its characteristic
appearance help with this process. The gray
scales trap water underneath them when it rains, and
the moisture is then gradually absorbed by the plant.
Live oaks and bald cypress seem especially well
suited for harboring this plant, and many of our older
live oaks and bald cypress have at least some Spanish
moss in them. But Spanish moss may be seen
growing in many other tree species, as well as on
dead trees, fences and even electrical power lines.
Because people sometimes see Spanish moss
growing on a dead branch or tree, they mistakenly
think the moss killed the branch or the tree, which is
incorrect. The branch or tree died for other reasons,
and the moss is simply growing there.
Although Spanish moss does not obtain any nourishment
from a tree, under certain circumstances
it can become a nuisance. If a weak limb becomes
heavily laden with moss, it could break off. Spanish
moss causes the most trouble in economic crop trees
such as pecans. In shade trees, the only real reason
for removing the moss is if you don’t like the way it
looks – not because of any damage it might do.
If removal of moss is necessary, mechanical removal
is the preferred method. There are no herbicides
labeled for controlling Spanish moss in trees. A
long pole with a hook or a long-handled rake is useful
to remove moss from lower branches. Many tree
companies will perform mechanical removal with a
bucket truck to reach high branches.
On the other hand, some people want moss to grow
in trees that don’t have any moss in them. You may
gather living moss and simply hang it from branches
in the tree where you want it to grow. If the growing
conditions are to its liking, the moss will become established
and grow in the tree. If
not, it will die. There is nothing
you can do if that happens–except
perhaps try again.
In nature, most new Spanish
moss plants sprout from a
seed. The tiny, greenish flowers
of Spanish moss produce a
seed pod that turns brown and
splits open when mature. The
seeds inside are equipped with
feathery parachutes that allow
them to float through the air like
dandelion seeds until they lodge
on a tree trunk or other suitable
spot to grow. Strands and tiny
pieces of moss carried by wind
or birds to suitable locations also
can grow into new plants.
In former times, moss had a
variety of uses in upholstery.
It was used to stuff everything
from car cushions to horse collars,
but it was mainly used in furniture
manufacturing. Fresh moss was gathered and
cured by wetting it down and packing it in trenches or
pits. It usually remained in the pits for six months to
eight months, in which time the outer covering rotted
off, leaving the inner strand.
At the moss factory it was then sorted and cleaned
and baled for shipment. Quite a few southern gardeners
made at least a part-time living from collecting
Spanish moss. The last operating factory in the South
was located in Gainesville, FL. That factory burned
down in 1958 and did not reopen.
Although Spanish moss is reported to be sensitive
to air pollution; you would think it would not grow in
urban areas with lots of cars but you can occasionally
see it growing in landscapes across the Galveston/
Spanish moss also adds character to many live
oaks in local parks. Whether you appreciate its appearance
or wish it would go away, remember Spanish
moss is harmless to the trees.
By: William M. Johnson