QUESTION: My Arizona Ash trees have long dark streaks
running down their bark, and blobs of off-white or yellowish
goo at the top of each streak. Is this a bug or a disease?
I've had an unusually small outbreak of tent caterpillars
this year-- about the only sign of insect problems I've
seen. These trees are between 20 - 30 years old. Please
tell me what, if anything, I can do to get rid of the problem
and save the trees.
ANSWER: Old Arizona ash trees in Southwest Texas
are prone to have borers under the bark and into the wood
layers. This sounds like a wound response--lots of sap oozing
out (yellow material), perhaps fermenting along the way,
with liquid dripping down the bark leaving the dark wet
streak. You must be in an area with lots of summer rainfall
this year. Considering the age of the trees and suspected
borer damage, you should expect them to decline rapidly
within the next year or so. They will have to be removed.
Get at least 3 bids from dependable tree trimmers when the
QUESTION: I want to plant a vegetable garden in my
back yard. The site I've chosen is located directly beneath
a security light. This light comes on at dark and goes off
at dawn. Will the constant light, day and night, inhibit
the growth of my vegetables? (Tomatoes, broccoli, cauliflower,
fall and spring vegetables) We live in Northwest San Antonio.
ANSWER: Absolutely no effect. The longer light period
may in fact be beneficial even though it may attract more
caterpillar-laying moths and June beetles.
QUESTION: What causes my cucumbers to become bitter-tasting?
ANSWER: Any stress on a cucumber plant, such as
high temperatures, low moisture, low fertility or foliage
disease can contribute to bitterness. Bitterness is usually
associated with fruit harvested late in the season from
unhealthy, poor-yielding plants. Once a plant produces bitter
fruit, remove it from the garden because all subsequent
fruit will be affected in a similar manner.
QUESTION: I love figs, but I have never prepared
them myself. My neighbor's tree is loaded right now and
they are falling on the ground. I have about 5 pounds in
my dehydrator right now but they don't appear to be getting
brown like those dried figs in the market. Please advise
me if I'm not taking all of the steps. I want to get more
figs before the birds get them.
ANSWER: Do not worry about them getting darker.
They will take 15-20 hours in a dehydrator and 4-5 days
in the sun. Unless you are in a very low-humidity area,
sun drying is not practical The oven should work. Set it
at 120-145 degrees F. I am told that a 1-minute exposure
to boiling water will help the process. You want to dry
them until leathery, with flesh that is pliable, yet slightly
sticky, not wet.
QUESTION: Last October, we put down St. Augustine
grass in our yard, so it is not quite 1 year old. During
the past several months we have noticed more and more Johnson
grass. What can we do to get rid of it? Will it over take
our St Augustine??
ANSWER: The only herbicides (weed killers) which
you can use on St. Augustine and not kill it are Ortho Weed-B-Gon
for Southern Grasses and Greenlight Wipe-Out. For Johnson
grass, you may have to spot treat (spray or wipe on each
individual plant) the plants with a glyphosate herbicide
such as Roundup, Ortho Kleanup or Finale. After you get
rid of the rhizome Johnson grass, and the St. Augustine
gets well established, you should not have this problem
QUESTION: Can you help me with a tree question? My
Magnolia tree is in terrible shape! I live in east Dallas
in a home built in the 40's. I suspect my tree is around
the same age as my home. It has almost no flowers on it
(and has not all year), and the leaves are droopy. The tree
is very large, over thirty feet high and none of my local
nursery people have been able to help me. Can you?
ANSWER: Magnolias will naturally shed last year's
leaves and replace them with new leaves. However, the severe
drought of '96 damaged the root system of most magnolias.
Some died. If yours is re-sprouting and just dropping leaves
to re-adjust the top portion to the bottom portion which
was lost, it will grow out of this problem in a year or
two. There is little you can do; if you want to deep water
around the tree once every several weeks, that might help.
This is a common problem this year.
QUESTION: Two weeks ago I planted 15 striped maiden
grass along with about 100 other plants All of the plants
are doing fine, with the exception of 7 of the maiden grass.
They are wilted and turning yellow. They were watered daily
the first week, and now I water every other day. I put one
tablespoon of fertilizer in the bottom of the hole, and
nothing else. Any thoughts on what might be happening to
that half of the maiden grass?
ANSWER: Maiden grass should be easily established
but is VERY sensitive to over-watering. Being "watered
daily the first week and now watering every other day"
has rotted the root system. STOP watering!!! And water only
when you cannot feel moisture around the root system of
the plants when sticking your figure in the soil next to
the plants. I imagine that by now, some of the stems can
be pulled from the clump and should show a rotted area at
the base. It is possible that the clump will initiate new
growth if the damage is not to severe. They are very drought
tolerant once established, but moisture must be carefully
monitored during the establishment period. The fertilizer
did not do any harm.
QUESTION: I don't know if this is in your line of
work, but how do you propagate mesquite trees? I live in
Elephant Butte in New Mexico and we have plenty of mesquite
bushes, but their tap roots go down so far, that if you
try to dig them up, they die. Any suggestions?
ANSWER: Planting seed or digging very small seedlings
would be your best techniques.
QUESTION: I eat a lot of broccoli. But I eat it a
different way--I cut off the stem just below the flowering
part and eat only the flower. I discard the stems. Is there
just as much nutritional content in the flower, or is it
all in the stem? Is there a percentage of how much nutritional
value is in the flower and stem separately expressed as
a ratio to the overall nutritional content? In other words,
does the flower have say, 50% of the nutritional content
and the stem has the other 50%, or is the nutritional value
spread equally throughout the plant? What I'm concerned
about is that I may be throwing away the real nutrients
in broccoli. But then again, I go through a lot more packages
of broccoli than the normal person, which means more profit
for broccoli growers. And lastly, is there more nutritional
value in fresh, uncooked broccoli than broccoli which has
been boiled? And what about the difference between frozen
ANSWER: The stalk contains a significant level of
Vitamins A&C and other nutrients. The florets have a
higher concentration of these nutrients, but only about
20% higher. This is based on raw product. The stalks have
to be cooked longer for tenderness, therefore the nutrient
level will be reduced. I don't have exact figures on how
much. A dietician may have this information. The American
Dietetics Association also would be a good contact.
QUESTION: I know how to treat poison ivy as a rash,
and I know how to kill the plant. My question is, how do
I know if the plant in my back yard is poison ivy? I know
it has 3 leaves branching from the same place on the stem,
and that it can be everything from a small plant to a large
vine. However, almost all the ground cover in the back yard
fits this description. Are there any other plants that resemble
poison ivy (Virginia Creeper) that are really harmless,
and how do I know for sure?
ANSWER: The two plants most commonly confused with
Poison Ivy are Virginia Creeper and Box Elder. Virginia
Creeper leaflets arise from a central point on the leaf
stalk resulting in a whorled or palmate arrangement. Poison
Ivy leaflets arise opposite each other on the leaf stalk
with the terminal leaflet having a longer stalk than the
2 laterals. Box Elder leaves are arranged opposite on the
branch whereas Poison Ivy leaves arise from the branchlets
in an alternate fashion. They say a picture is worth a thousand
words. I recommend that you go to the library and look at
some field guides that compare the plants mentioned above.
--Paul Cox, San Antonio Botanical Garden
QUESTION: I have 6 tomato plants that are right under
the edge of a black walnut tree. I'm afraid that in time,
the tree is going to kill them. The plants are setting fruit
already. I am using only horse manure on them. Do you have
any other suggestions what to do to keep them going?
ANSWER: First, you should know what will eventually
kill your tomato plants. Roots of black walnut trees release
a substance called juglone, which kills roots of sensitive
plants. Tomatoes happen to be among the most sensitive,
and should not be planted within at least 50 feet of these
trees. Juglone is emitted from living and dead roots and
can persist in the soil for over a year, so avoid areas
where juglone producing trees have grown for 2 to 3 years
after removing the trees. Shade can also be a problem --
productive tomatoes need 8-10 hours of direct sunlight daily.
For more information about growing tomatoes, see the write-up
at this website:
It sounds to me as if you have done everything humanly
possible to have a tomato crop near a walnut tree.
QUESTION: My tomato fruit have small yellow specks
on the surface. When the tomatoes are peeled, those yellow
specks form a tough spot that must be cut off before eating
the tomatoes. What's wrong?
ANSWER: The yellow-speckling is caused by sucking
insects such as stinkbugs or leaf-footed bugs. Early control
of sucking insects that feed on the fruit is helpful in
alleviating the problem. The stinkbugs have been plentiful
Then there is always the problem of plant stress -- any
of which causes the fruit to be smaller and the skin to
be tougher. Very hot weather, which causes the plant to
slow its reproductive growth, or being constantly wet or
often dry (the plant wilts severely) all cause stress and,
consequently, tough-skinned tomatoes.
Find some Surefire tomato plants and plant them now for
an abundant fall harvest. Fertilize them heavily (mix Osmocote
slow-release fertilizer pellets into your container mix)
and often. Water with a water-soluble fertilizer such as
Miracle-Gro, Rapid Grow or Peters 20-20-20 EVERY time you
water. Then, get ready for some good eating come October!