Each fall, a glorious spectrum of colors blankets the
hardwood forests in many areas of the United States.
I grew up on a family farm located in South Central
Virginia and I looked forward to the fall season every
year. Each fall, the area would be covered in a quilt
of colors so vibrant that even a teenager would likely
In Colorado, it’s the gold of aspen trees that catches
the eye. In New England, it’s the brilliant oranges and
yellows of the sugar maples. And in the South, it’s the
deep scarlet of the red oaks, the reddish-orange of
sumac and the multicolors of sweet gum.
Despite appearances, Mother Nature doesn’t paint
with broad brush strokes. Paint-by-numbers would
be a better analogy because each tree has its own
fall color bound up in the chemical composition of the
sap, which provides the “instructions” on what color
Tree leaves change colors according to complex
chemical formulas. Depending on how much iron,
magnesium, phosphorus or sodium is present in
leaves and the acidity of tree sap, leaves might turn
amber, gold, red, orange or just fade from green to
brown. Scarlet oaks, red maples and sumacs, for
instance, have a slightly acidic sap that causes the
leaves to turn bright red.
The leaves of ash trees growing in areas where
limestone is present will turn a regal purplish-blue.
What prompts the change? Although many people
believe that a mischievous Jack Frost is responsible
for the color change, weather conditions are just one
factor at play. As the days grow shorter and the nights
longer, a chemical clock inside the trees starts up,
releasing a hormone which restricts the flow of sap
to each leaf.
As the autumn season progresses, the sap flows
more slowly and chlorophyll, which gives most leaves
their basic green color over the spring and summer
seasons, starts to disappear. The residual sap becomes
more concentrated as it dries, creating the
colors of fall.
In other words, the colors are always there, but as
the predominant hues of green fades, other colors
become enhanced and begin to show through. Sunlight,
nutrients and moisture level factor into the process
and cool weather seems to slow things down to
bring out the full effect.
Obviously, this area is not a hot spot for fall color
along the roadways as we don’t have the aspens
of Colorado nor the sugar maples of New England.
Along the highways in Galveston County — well, it’s
basically the orange, yellow and red hues of the maligned
Chinese tallow and a few other trees.
I was pleasantly surprised to see one tree species
providing an unexpected burst of fall color. Last week
while walking back to my office from the Discovery
Garden in Carbide Park in La Marque, I noticed a
colorful layer of fallen leaves below the canopy of a
Texas ash (Fraxinus texensis). The leaves from this
tree were a striking yellow-gold in color but leaf colors
in the fall also range from gold, orange and purple depending
on local conditions. The crape myrtle in my
backyard produced a maze of yellow, red and copper
colored leaves that provided a glimpse of fall color. A
few blocks from my home is a neighbor’s mature and
very tall bald cypress. I have witnessed the tree’s foli age
turn from a soft green to a striking bronze color
over the pass weeks as I drive to work.
Yes, fall colors in our urban forests along the Texas
Gulf Coast do not hold a candle to those in many
other areas of the nation. However, it seems that life
is often about trade-offs — in this case, I find ample
solace and much happiness in living in an area with
very mild and pleasant winters.
Seminar on The Jewels in the Garden . . . Hummingbirds
Galveston County Master Gardener Deborah Repasz’s
presentation will include the fight and flight
for survival of hummingbirds in Galveston County.
Repasz will highlight ways to increase hummingbird
sightings in your yard by creating an inviting habitat
using shelter, food, and water. Plants, including Texas
natives, and other resources that attract hummingbirds
will be presented, as will the impact of pesticides
The seminar will be conducted on Saturday, December
8, from 1:00 – 3:00 p.m. at the Galveston
County AgriLife Extension Office located in Carbide
Park (4102-B Main St. in La Marque). Pre-registration
is required (phone 281-309-5065 or e-mail galvcountymgs@
gmail.com) to ensure the availability of handouts.
Master Gardener Class Applications
Applications for the 2019 Master Gardener class
are due on Thursday, December 6. Applications can
be picked up at the Galveston County AgriLife Extension
Office located in Carbide Park (4102-B Main St.
in La Marque) or downloaded online (https://aggiehorticulture.
tamu.edu/galveston/). Classes will be
held from Tuesday, February 5, and on each Tuesday
and Thursday thereafter through April 11.
Trees and other plants along highways and home
landscapes have provided a respectable display of fall
color over the past weeks. Although Chinese tallows are
considered an invasive tree species, they have provided
eye-catching displays of fall color.
PHOTO CREDIT: William M. Johnson