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December
23, 2004
Hortiscope
Ronald C.
Smith, Horticulturist
NDSU Extension Service
Q: We have about 50
American willow trees. I noticed the leaves are dropping on a few of them.
There are many small black insects on the branches. They are about an
eighth-inch long and seam to be eating large holes in the leaves. Can
you tell me what they are and how to control these pests? Are the trees
in danger of dying from this problem? (e-mail reference)
A: Willows are besieged
by a vast array of insect and disease pests. Since the trees are not
in flower and there is little chance of bee damage, I would spray a
low-toxicity insecticide such as Insecticidal soap to see if you can
reduce the population somewhat. Insecticidal soap is effective only
if contact is made. If this doesn’t do a satisfactory job, then
try using Sevin or Malathion. I don’t know what the insects are
based on your description. It could be beetles of some sort. I doubt
the trees are in danger of dying from this attack, but it will weaken
the willows somewhat and open the door for other organisms to move in.
Q: I’ve got
a nasty case of rust. It seems to have originated on the west side of
our property where some mature wild plum trees are growing. They were
infested with a mix of fungus last spring. I’ve written them off.
The rhubarb in the vicinity of the plum trees is now plum dead.
The rust appears
to have migrated to the east. I have second-year sown grass adjacent to
(east of) the plum trees that is so rusty, it turns my shoes orange when
I walk in the grass. Adjacent to the grass is second-year sod, which does
not show signs of the rust. Our house is next to the sod, but is surrounded
by river rock. Will the foundation plantings in the river rock perish?
The foundation plantings are within 20 feet of the sown grass with rust.
I’m concerned the rust is migrating across my yard with the prevailing
winds. It appears to have killed two crimson king maple trees I planted
this spring. (Fergus Falls, Minn.)
A: Rust is usually
associated with an alternate host and appears on newly seeded grass.
At this time next year the rust should be a thing of the past. To help
your lawn out now, apply a small amount of fertilizer and water it in.
This will stimulate new growth, which will allow you to mow, bag, and
dispose of the clippings. The rust that is on your grass will not hurt
your other ornamental plantings. Your crimson king maples did not die
from rust fungus. Something else did them in.
Q: My fiancé
and I are planning on getting married. The bouquet that I would like to
carry is Easter lilies. We would like to plant them so they come back
every year. How do I plant the lilies after they were in a bouquet? Is
there another type of white flower that could be put into a bouquet and
then planted hours later? (e-mail reference)
A: Bouquet flowers
will not grow in to plants in your garden. However, if you can get someone
to give you Easter lilies as plants for a wedding gift, they grow nicely
in any garden and will remind you of your continually growing love for
each other. You could carry the bouquet of lilies in your hand, with
the potted lily plants surrounding your wedding ceremony. Nice idea
and congratulations!
Q: I have a client
with a bleeding heart planted on the south side of the house. It has turned
brown, but I don’t think it is a water problem. Can it be cut back
and will it come next year? (Forman, N.D.)
A: Dying down after
flowering is a normal part of the bleeding heart lifecycle.
Q: I have ants congregating
on the underside of my sunflower leaves. What in the world are they doing?
Also, every year when my peonies bloom they are covered with ants. Do
the ants somehow help the peonies? (e-mail reference)
A: The ants have
probably found some aphids or mites that are producing honeydew (excrement)
that the ants are harvesting for their nests. With peonies, the flower
bud scales secrete sap that is also rich in carbohydrates that the ants
can use as a food source. It was thought that ants were necessary for
peony flowers to open. That theory is not true, according to research.
Without any ant activity, the flowers still open.
Q: Some of my calla
lilies are producing seed pods and I would like to know how I can harvest
them to make them grow next year. (Velva, N.D.)
A: All of my references
state that using seed to produce calla lilies is impracticable for most
home gardeners because the lilies require special treatment and carefully
controlled conditions. Propagation by off-shoots and division is the
best way to go.
Q: We have a huge,
twisted willow (all the small branches are twisted and bent) that seems
to be under some sort of attack. I didn’t realize that something
had been eating away at the core of the main branch. I assumed it had
just died and was rotting via microbial degradation of some sort. I cleaned
out all of the dead wood and treated the tree with a typical wound dressing
material. Yet, every few days, I can still find accumulating at the bottom
of the hole what appear to be very uniform, small shavings or slivers
of wood about a quarter-inch long. These slivers are intermixed with fine,
dry wood dust. I have not seen an insect on the tree. I’ve surface
sprayed it with Malathion, Sevin and Diazinon, but there was no effect.
Any ideas?
A: Sounds like a
borer problem. All the topical applications of insecticides won’t
make a difference. If the tree is important to you, and I assume it
is, contact an International Society of Arboriculture certified arborist
to see if it can be saved. The arborist may be licensed for special
injectable insecticides that may be able to stop the borer activity.
Q: I am fairly new
to the gardening world and have a question to ask about our thunderchild
crabapple tree that we recently planted. It has developed three suckers
quite near to and below the base of the soil line. How do I go about removing
the suckers and what would happen if they aren’t removed? (e-mail
reference)
A: Any sucker growth
coming up from the base of the tree will simply rob the scion or budwood
of the tree (top part) of nutrients. If they are not removed, the suckers
will eventually takeover the tree. Cut them back to their origin, and
spray the area with RTU (Ready To Use) Sucker Stopper, which should
be available at a good garden supply store.
Q: I am hoping you
can provide me with the name of a product to apply on cottonwood suckers
growing in my lawn. (Onida, S.D.)
A: I’m assuming
the roots are still attached to the tree that you want to keep. If that
is the case, locate some RTU Sucker Stopper. It may be available in
a local garden center. It can also be found at www.montereylawngarden.com
or call (559) 499-2100. They are located in Fresno, Calif.
Q: What is the name
of the winery in Bowman or in the southwestern part of the state? Do you
know of others in western N.D. beside Pointe of View Winery in Burlington?
(e-mail reference)
A: It is the Golden
Valley Winery. Their phone number is (701) 523-2949. The names of the
proprietors are Brian and Roxanne Loken, very nice folks.
Q: I read the information
on peonies, but saw no reference to the seeds. My peonies formed seed
pods that I allowed to mature. The pods eventually dropped seeds all around
the plant. I would like to know if they can be successfully grown this
way. (e-mail reference)
A: It normally takes
five to seven years to produce a flowering peony plant from seed. The
propagation is complicated by what is known as “epicotyl dormancy.”
What this means is that the seed needs to be sown in a moist medium
at room temperature and, after the roots have developed, transplanted
to pots placed in a cold room (40 to 50 degrees) or outdoors in winter
for two and a half months. This overcomes the dormancy that exists in
the shoot tip, which then should grow readily into a plant when moved
into warmer temperatures. For that reason, many folks just divide their
peonies!
Q: I have a goldfish
plant and have made many cuttings from it to share it with friends and
family. The cuttings seem to be thriving, but do not bloom! What am I
doing wrong? (e-mail reference)
A: Why does everyone
assume that they are doing something wrong when the plant doesn’t
respond the way they expect? You could be doing everything right and
still have it not flower.
Usually the non-flowering of a houseplant is due to one or a combination
of factors such as too low a light intensity or duration, inappropriate
temperature regime to bring it into flower, over-fertilization with
a high nitrogen material, drafts of hot or cold air, inappropriate watering
cycles or the plant remaining in the juvenile stage.
Q: Your name came
up on the Internet when I did a jade plant search. I am a follower of
the principle of feng shui, where positive flows of energy can be enhanced
by certain species of plants. My husband and I are going through some
financial difficulties right now and the jade plant that I have had for
more than six years is now looking poorly, with part of it obviously dying.
Is there anything I can do to improve the well-being on my jade and our
financial health as well?
A. Knowing nothing
about feng shui, I had to look the words up in my dictionary. It says
feng shui is “the Chinese practice of creating harmonious surroundings
that enhance the balance of ying and yang.” After further digging,
I found that jade plants can enhance prosperity. So it is in your self-interest
that the jade becomes healthy again in order to help your financial
situation. Jade plants need plenty of light, modest to minimal water
during the winter months, fertilization during active periods of growth,
regular pruning to keep them from becoming top-heavy and monitoring
for scale, mealybugs, and spidermites. Jade plants need to be repotted
in the next nominally-sized pot when they become pot-bound. Use a freely-draining
container that sits in a saucer. The pot should drain within 20 minutes
of a good watering. Jade can be easily propagated via leaf or stem cuttings.
Check my Web page on jade plants at www.ext.nodak.edu/extnews/hortiscope/houseplnts/jade.htm
for more information.
Do you have a gardening
or houseplant question? Write to Hortiscope, Box 5051, NDSU Extension
Service, Fargo, ND 58105 or e-mail to Ron Smith at ronsmith@ndsuext.nodak.edu.
Note to e-mail correspondents: please identify your location (city and
state) for most accurate recommendations.
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Source: Ron
Smith, (701) 231-8161, ronsmith@ndsuext.nodak.edu
Editor: Rich Mattern, (701) 231-6136, richard.mattern@ndsu.nodak.edu
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