| Q: |
I am trying to spray my Aspens
w/fungicide. It says to do at budbreak the first time. When is and what does
the budbreak look like? Will there be a leaf? Our spring is very late here
so I want to do it at the right time. M. T., Bend. OR; 3/13/08 |
| A: |
Budbreak occurs at slightly
different times in spring, influenced largely by weather conditions. In
spring little nodules develop on branches. As the weather warms up
these little nodules split open and you can see the little green leaves
that are forming. This stage is called budbreak. Do not wait for the
leaves to be fully formed.
|
| |
|
| Q: |
Will puncturing the bark of a
trembling aspen induce black rot? Is there a way to attach a structure to an
aspen without killing the tree? Please pass on any information you have
regarding these matters. Thanks. B. B., Winnipeg, MB; 2/2/08 |
| A: |
Within the trunk of a tree are
tube-like structures that transport water and nutrients up to the top of
the tree and ones that transport sugars down to the roots. If these are
badly damaged by punctures the water, nutrients and sugars can't be
transported and the tree will die. In addition, puncture wounds in the
trunk provide a path for disease organisms and pests to invade the
trunk. Therefore, puncturing the trunk of a tree is not recommended.
|
| |
|
| Q: |
When should I trim a maple tree
in the Littleton/Highlands Ranch area? G. G., Littleton, 1/14/08
|
| A: |
You should avoid pruning maple
trees in late winter or early spring. Maples ooze sap, called "bleeding,"
when pruned at that time. You can prune the maple tree after it leafs out
in spring. |
| |
|
| Q: |
Do willow hybrid trees stay
green year round? I'm considering getting some to use as a fence tree.
Thanks, J., Fayetteville, GA; 12/9/07 |
| A: |
No, the willow hybrid does not stay green year
round. It is a deciduous tree. |
| |
|
| Q: |
We live in Reunion - Commerce
City, and have just had 2 clumps of aspens planted along our east-west
fenceline between our home and our neighbors. A very reputable nursery
planted them for us at the end of September. The first 3 weeks were met by
very windy and warm weather - the wind blew half of the leaves off and now
the remaining leaves have turned dark green, black, crispy, and are falling
off. I fertilized lightly with a root stimulator and good water about the
third week, and they have had good water three times a week. They have not
been overwatered. My father-in-law says they may be "stressed out" from
being planted and subject to those strong winds we had a month ago. Was I
right or wrong to lightly fertilize? Is it normal for them to have black
leaves that crisp up and fall off? The branches of the trees are bendable,
so I know they are not dead. How normal is this 6 weeks after planting?
D. C., Commerce City, 10/17/07 |
| A: |
It is common for newly planted
trees and shrubs to go through "transplant shock." The root system
needs a few weeks to adjust after being disturbed when planted. The
roots will struggle to provide enough moisture to the rest of the tree.
Drying conditions such as high temperatures or windy weather make the
problem worse and can lead to leaf drop, brown edges, etc.
Newly planted trees and shrubs should
not be fertilized. The fertilizer promotes growth of additional leaves
at a time when the roots are already struggling to support the moisture
needs of the existing leaves.
Continue to water the trees regularly.
During winter you should water them about twice a month if there is
little or no snow. Water early in the day when the ground isn't frozen.
When the leaves fall this autumn be sure
to rake them up and get rid of them. Disease organisms and pests can
over-winter in fallen leaves and then attack the trees in spring.
|
| |
|
| Q: |
I have two Aspens along one side
of my house that are growing too close to the house. One is about 6" thick,
the second one is 4". I want to transplant them to a more open area in the
front. I will be doing it myself. Is this a do-able job? What time of
year would be best? What reaction from the trees can I expect? Thanks!
S. M., Denver, 10/10/07 |
| A: |
Transplanting such large trees will
be a challenge. Their root systems are very large and only a small portion
can be dug up. Early spring is the best time to transplant the trees.
Water them well a few days prior to digging them up and keep them well
watered after planting them. Unfortunately, you may lose them, but it is
worth trying since they need to be moved from their current location. |
| |
|
| Q: |
It is mid September and I have
received permission to dig trees in an area that is about to be developed.
First question is what is the proper way to dig trees for transplanting? The
area has Spruce and Aspen and I would like to transplant them to San Luis
Valley where I own property. Is mid September to early to dig up these types
of trees and what care is needed so they survive after transplanting to them
to this area? Seems like a waste to let these trees be destroyed and I very
much would like to plant some on a treeless property! Please help with
digging and transplanting information. P. W., Fountain, 9/11/07 |
| A: |
Planttalk Colorado has
two articles that explain how to dig up and transplant a tree. Please
see
www.ext.colostate.edu/ptlk/1717.html. After reading it click
on message number 1711 (near the bottom of the page) for more
information. You may be able to transplant the aspens successfully in
fall, but the spruce trees will be a challenge. I suggest that you buy
a product called Wiltpruf to spray on any conifers you transplant. It
helps the trees retain moisture during winter. Small trees are more
likely to survive being transplanted than large trees.
|
| |
|
| Q: |
I just pruned a large broken
branch from my Aspen tree. The branch was about 2" in diameter. Would it be
a good idea to spray the cut spot with one of those "tar" type petroleum
based products for protection? J. O., Thornton, 8/27/07 |
| A: |
Sealants generally are no longer
recommended on pruning cuts. The tree will form a callous over the wound
for protection. |
| |
|
| Q: |
I have two beautiful Linden
trees that border my house in the space between the sidewalk and street here
in Denver. One of the trees has severe browning of the leaves every summer.
It is now mid-August but the half that faces North looks miserable. Is the
tree diseased? P. S., Denver, 8/21/07 |
| A: |
I suspect the leaf browning is
due to damage or disease affecting the roots or trunk of the tree. It
might be worthwhile to contact a tree service company to examine the
tree. They can diagnose the problem and suggest appropriate treatments.
|
| |
|
| Q: |
I have a honeylocust tree newly
planted last September in a sodded area that started to leaf but now the
leaves are smaller than they should be, yellowish and dry. We are near
Elizabeth, CO, elevation 6600 ft. The soil is clay/sand mix. The soil
seems moist but not overly wet, no evidence of insects, bark has what looks
like scratches on it. We had a light frost about 10 days ago. What can I do
to keep my tree alive? C. D., Elizabeth, 6/12/07 |
| A: |
Honeylocust trees in much of
Colorado's Front Range are doing poorly this year. Our weather this winter
may be a factor. All you can do at this point is keep the tree watered well
(but not over-watered) and perhaps fertilize it lightly. If the sodded area
it is planted in has been fertilized do not add additional fertilizer.
Also, you should avoid using Weed 'n Feed products on the sodded area. They
can harm the tree. While the tree is young be sure to wrap the trunk with
tree wrap from late fall to early spring to avoid sunscald. The scratches
could be caused by cats, they may be cracks caused by sunscald, or if you
see gnawed areas they may be due to voles. A stressed tree is more likely
to be attacked by pests and diseases. Inspect the tree regularly and treat
promptly if you see signs of these. |
| |
|
| Q: |
I live at 7500 ft. outside
Monument, CO. I had someone plant in November 2006 20 Pinon Pine trees in
my yard. I already had some Pinons and Ponderosa pines that were doing
great. However, the newly planted Pinons are turning brown. They were in
snow from late November through March 2007. What can I do to save them? S.
G., Monument, 4/2/07 |
| A: |
Lots of pines are showing signs of
damage from this winter's weather. Unfortunately, there is little you can
do to help them. As the weather warms up check the soil regularly and water
the trees when the soil becomes dry. Water thoroughly and allow the soil to
dry out before watering again. Pines don't like soggy soil. If you need to
replace any of the trees I suggest that you not do so in the heat of summer
or in fall. Fall-planted conifers are prone to winter damage and die-off. |
| |
|
| Q: |
Will pruning a maple tree in
January kill the tree? C. S., Scottsville, KY; 3/27/07 |
| A: |
Pruning a maple tree in January is
not recommended, but it won't kill the tree unless done really badly (too
much of the tree removed at once, jagged cuts, torn bark, etc.) |
| |
|
| Q: |
Do you have any advice about
what trees to plant in a small backyard with not very much width room?
N. S., Denver, 3/26/07 |
| A: |
Some small trees that don't
grow too wide include these:
Chanticleer Pear (Pyrus
calleryana 'Chanticleer') 25' x 15' -- fruitless
Newport Plum (Prunus
cerasifera 'Newport') 25' x 15' - fruitless
Canadian Cherry (Prunus
virginiana 'Shubert') 30' x 20'
|
| |
|
| Q: |
I have a large autumn blaze
maple in my yard that just started oozing sap, dripping down the trunk, and
off branches. I do not recall this happening in the past. Could there
be a problem or just a natural happening? K. R., Loveland, 3/5/07 |
| A: |
I suspect the maple tree has frost cracks
that are oozing sap. This is a fairly common occurrence when we have
freeze/thaw cycles. Cracks in the bark are created when it freezes. Then,
when it warms up a bit the sap seeps through the cracks. |
| |
|
| Q: |
The tree nursery said it was
okay to plant a ponderosa pine in the fall, so we did. I watered it after
two hours, maybe too much. It started looking yellow after five hours.
What can I do? M. N., Castle Rock, 11/10/06 |
| A: |
When you plant trees they should be
watered deeply and immediately. I doubt you harmed the tree by watering
it. The tree is probably going through transplant shock while it
adjusts to being planted and to being in a new home. You will need to
water it during winter. Check the soil frequently. If it is dry, water
the tree early in the day to prevent freeze damage. It would also be a
good idea to spray it with WiltPruf, a product that will help prevent
moisture loss. Evergreens can dry out in winter and then die.
|
| |
|
| Q: |
How do I know when to trim
back shrubs and trees? I live in Peyton, CO, and am not as up to date
with tree and shrub types in my garden. Thank you. J. M.,
Peyton, 9/30/06 |
| A: |
Most deciduous trees (trees that lose
their leaves) are usually pruned in late winter or early spring before
they leaf out. Maple, birch and walnut trees tend to ooze sap if pruned
when dormant, so they are usually pruned in spring after they leaf out.
Avoid pruning in late summer. Evergreen trees can be pruned anytime
when needed.
Flowering shrubs such as lilacs
generally are pruned as soon as they finish blooming. Non-flowering
shrubs are pruned in late winter or early spring. Avoid pruning
them in late summer.
|
| |
|
| Q: |
We live in Morrison, CO, and
have 2 young (4-5 year old) corkscrew willow trees that are growing and
healthy. However, this year we have noticed the trees are full of small
bees. Do we need to worry about damage the bees might do to the trees?
S. W., Morrison, 9/7/06 |
| A: |
Willow catkins produce nectar and pollen
that attract bees. Also, if the trees have aphids, which produce a
sweet sticky substance called honeydew, the bees are attracted to it.
The bees won't harm the trees.
|
| |
|
| Q: |
We live in Elizabeth, Colorado,
and have many Ponderosa Pines, which we love. However, we would like to
plant a different kind of tree in the front area (we live on 2 acres). What
types of trees would be good for our area, as we are a little higher in
elevation? Can we plant them in the fall? Thanks for the information!
K. B., Elizabeth, 9/6/06 |
| A: |
Yes, you can plant deciduous trees in the
fall. It is a good time to plant almost everything except evergreen
trees. Evergreens planted in fall lose moisture through their needles
in winter and dry out. This often results in their death.
If you want shade trees, Ash trees are a
good choice. Hackberry, Catalpa, Linden, Oak and Cottonless Cottonwood
are also popular. Avoid Aspens -- they are too prone to pests, diseases
and suckers.
Smaller trees that do well are
Crabapple, Hawthorn and Callery Pear. They have blossoms in spring.
|
| |
|
| Q: |
What are the planting
requirements for an ash tree? For example, how far from a structure
should one be planted, how large will it grow and should it be in part
shade or full sun? Thank you! C. B., Aurora, 8/24/06 |
| A: |
Ash trees perform best when planted in
full sun. They prefer regular watering. Most grow 40 - 60' tall and 20
- 40' wide. Therefore, the tree could be planted about 20' from a
structure.
|
| |
|
| Q: |
Hello, I live in Canon City,
CO, and I want to plant a Crimson King Maple. Will it grow in this area?
Send me an idea of what Maples would do good here. Please let me
know. Thanks , L. A., Canon City, 7/25/06 |
| A: |
'Crimson King' Maple is one of the
cultivars recommended for Colorado. It should grow in your area. Some
other recommended cultivars include 'Deborah,' 'Emerald Queen,' and
'Royal Red.'
|
| |
|
| Q: |
We are wondering if cypress
trees will grow in our Lakewood northern exposure landscaping? I.
F., Lakewood, 7/22/06 |
| A: |
Bald cypress (Taxodium distichum) trees
are a deciduous conifer that grows here.
|
| |
|
| Q: |
We were working on some major
overhaul of the landscape in the front yard and hit the roots of the aspen
tree with the tractor blade. It ripped up a root and that tore the bark in
the front of the tree. My brother-in- law says we killed the tree. Is
that correct? T., Montrose, 7/9/06 |
| A: |
The damage to the bark of the aspen
tree, if severe enough, can cause the tree to die. |
| |
|
| Q: |
Hi, I have some sort of
growth on my scrub oak. They are fuzzy spheres that are a lime yellow
color to red. They are on the underside of the leaves and are on quite
a few of my oaks. What is this and what do I do about it if anything?
Thank you, B. B., Colorado Springs, 7/5/06 |
| A: |
The spheres on the oak tree leaves
are probably galls produced by gall wasps. They are very common in
Colorado. Usually control isn't necessary. Insecticides can be sprayed in
late fall or winter when adults emerge and are laying eggs. |
| |
|
| Q: |
I have a Newport Plum tree in my
front yard that is about 10 years old. I have been fighting the growth of
little shoots all through my front lawn and a neighboring rock garden --
probably a 25-30 foot radius around the tree. I am afraid I will have to
destroy the tree, but I am not sure this will solve the problem if it is
coming from the roots of the tree. Any suggestions? S. G., Posen, MI;
5/16/06 |
| A: |
There is a product called Sucker
Stopper you can spray on the shoots of the Newport Plum to kill
them. Be sure to read and follow label instructions. Avoid getting
this product on the lawn.
|
| |
|
| Q: |
Buds on my Patmore Ash and
Honey Locust recently froze. Will they just come back automatically or
should I do something special to help trees? I am in Lakewood, Green
Mountain area. C. S., Lakewood, 5/3/06 |
| A: |
If the trees are healthy they should
recover and produce a new set of leaves. Keep them well watered. You
can also apply a bit of fertilizer to promote growth.
|
| |
|
| Q: |
We have just moved here and have
a large lot to landscape. We live in Falcon, which is windy, and want a
windbreak of trees. Our soil has some clay and we are wondering whether a
Ponderosa or an Austrian Pine will do better in high winds. Thank you. K.
B., Falcon, 4/12/06 |
| A: |
Both Ponderosa and Austrian pines
perform well as windbreaks. The Colorado State Forest Service rates
Ponderosa pines as "excellent" windbreaks and Austrian pines as "good"
windbreaks. |
| |
|
| Q: |
Is Autumn Blaze Maple tree a
good choice for planting in the Longmont area (weather and soil wise)?
Is the plant easy to grow? How can you ensure that it grows well
and healthy? Does the soil need extensive preparation before
planting this tree to ensure it grows well? S. K., Longmont,
3/2/06 |
| A: |
Autumn Blaze Maple is a popular
tree. It is a large tree, growing 45' high and 35' wide. It
likes moderate amounts of water -- similar to a lawn in its water
requirements. It has orange-red fall color. It is fairly
easy to grow and requires standard soil preparation. One drawback
is that it is prone to iron chlorosis.
This is a condition in which leaves become pale green or yellowish due
to an inability of the roots to absorb sufficient iron from the soil.
Applying chelated iron can control this condition if it develops.
|
| |
|
| Q: |
I would like any suggestions you
could give me regarding trees for my yard. We recently moved into a
new house here in Colorado Springs, and want to plant two trees in the
backyard. We would like something that grows to it's surroundings, and
has color. The area for the trees is 8 feet by 8 feet. The areas are
in the corners of the back yard and they receive the west sun in the
afternoon. I came out 4 feet from the fence with rock, and then made
the areas for the trees. The rest of the yard has grass. Any
ideas? Thank you for your help. S. M., Colorado Springs, 2/15/06 |
| A: |
It appears you have a fairly
limited area for the trees. The following trees are suitable for
smaller spaces:
Newport Plum (Prunus cerasifera
'Newport'): 25' tall, pinkish-white flowers, maroon foliage.
Spring Snow Crabapple (Malus): 20'
tall, white blooms in spring, a fruitless variety.
Centurion Crabapple (Malus): 25'
tall, rosy red blooms and fruit
Chanticleer Pear (Pyrus calleryana
'Chanticleer'): 25' tall, white blooms in spring, maroon fall color.
|
| |
|
| Q: |
I have a large, beautiful walnut tree in my back yard that has made
the yard uninhabitable! It is a haven for squirrels who, from April through
October, sit up there nibbling a few bites off a seed and hurling it down,
sometimes from two or three stories up. The heavy nuts become harmful
projectiles! Not only that, the partly chewed nuts, still in their green
hulls, become sharp litter all over the lawn, making barefoot walking next
to impossible! I'm also told the decomposing shells inhibit other
things to grow.
We had a tree collar put up and the squirrels hang out on it! I
love the tree but I have considered cutting it down because I want a back
yard I can be in. Someone suggested an understory net to catch the nuts,
which also sounds problematic. Is there anyway to keep the tree from setting
nuts? Any other ideas?
Thank you so much for any advice you can give me! L. G.,
Denver, 2/5/06 |
| A: |
I'm sorry, but I don't have any
solutions for the problems with the walnut tree. A net is a
possibility, but I foresee putting it up and maintenance as issues.
While there is a product available to limit fruit-set on fruit
trees, I am not familiar with anything for nut trees. |
| |
|
| Q: |
How do we trim years old
corkscrew willow trees? We just bought a house with two in the front
that have never been pruned. Please advise. B. K., Livingston, CA;
1/4//06 |
| A: |
You can
shape the corkscrew willow trees, removing no more than one third of the
branches annually. Topping trees (cutting off the ends of branches to
shorten the height of the tree) is not recommended because it results in
weak new growth that is prone to breaking. Instead, thin out problem
branches. Do not cut branches flush with the trunk. Cut them
just beyond the small bulge, called the branch collar, that is near the
trunk. If the branches are very large or if the trees are tall,
you might want to consult an arborist. |
| |
|
| Q: |
I live in Chicago and we have a
Horse Chestnut tree that needs to be trimmed back (no major branches). What
is the best time of the year to do this? Is there a time or temperature to
avoid (like middle of winter)? Besides the obvious concerns, we had a
hot/dry summer, and December has been pretty cold here so far, so I don't
want to cause any more stress to the tree if we shouldn't be trimming some
of it's branches now. Thanks! S. P., Chicago, IL; 12/7/05 |
| A: |
Early spring,
just before a tree's leaves open, is a good time to do pruning. |
| |
|
| Q: |
I live in Ohio and I want to grow a Pinus aristata in my
yard. I have failed twice. I put it on a bank and watered it and
mulched it, also. Will this tree grow in Ohio? I know its natural
habitat is high {10,000}feet and higher, but will it grow at lower sea
level? They seem to do OK during the first year and the next spring
the needles start turning brown and it dies. Help!!! J. W.,
Youngstown, OH; 9/29/05 |
| A: |
Bristlecone pine (Pinus aristata)
will grow in USDA hardiness zones 3 -
7. You live in zone 6, so it should
survive there unless there are problems
with the soil. Pine trees need good
drainage. They require little water
once established. Do not plant the
trees in summer when the weather is
hot. Also, do not plant them in fall.
Evergreens planted in fall tend to dry
out excessively during winter and then
die in spring. Plant them in early
spring. Keep the soil moist, not wet,
while they take root and gradually
reduce watering. Winter watering when
the soil isn't frozen may help the trees
survive dry winters. |
| |
|
| Q: |
I just purchased a new home in Aurora, and I have to provide my
own landscape. I would like to plant some trees along my fence line that's
open to the street for privacy. However, I am not sure what trees to plant,
and is it wise to plant these trees in the fall season? Please keep
cost in mind. I. M., Aurora, 8/29/05 |
| A: |
Spring is the best time to plant trees.
Fall is the second best time. Evergreen trees
should be planted in spring. Because they don't
have an established root system, winter weather
can dry them out and lead to their death. You
didn't mention how much space you have for the
trees, but I expect not a lot if you have a
typical yard. Because you want the trees to
provide privacy evergreens would be best.
Limber pine (Pinus flexilis) grows 15 - 20'
wide. Rocky Mountain Juniper cultivars such as
'Cologreen,' 'Wichita Blue' and 'Moonglow' grow
15 - 20' tall and stay narrow. |
| |
|
| Q: |
Could you please recommend some
possible trees/bushes that may fit into my back yard? I live in
Westminster, CO, and am in the process of landscaping my back yard. The
area is not very big, so I am trying to be careful about the type of plants
that I choose. I am looking for perhaps a tree that would provide some
shade or a bush for privacy. The area I would like to plant it in is
between my porch and fence, and about 2 1/2 ft by 2 1/2 ft, and gets full to
partial sun. M. F., Westminster, 8/16/05 |
| A: |
It sounds like the area for planting
a tree is very small. A columnar tree or shrub may work best. The
following are evergreens and would provide privacy.
Fastigiata Scotch Pine (Pinus
sylvestris 'Fastigiata'): 20' tall, 3 - 4' wide
Skyrocket Juniper (Juniperus
virginiana 'Skyrocket'): 15' tall, 3 - 4' wide
Medora Rocky Mountain Juniper (Juniperus
scopulorum 'Medora'): 10 - 15' high, 3 - 5' wide
|
| |
|
| Q: |
We have a huge, old cottonwood
tree that is the dirtiest tree we've ever seen. Can anything be done to
stop the tree from producing cotton?
We won't cut the tree down mainly because it is too expensive (over $2,500),
but it is making our lives miserable because of all the work cleaning up its
mess. D. S.; Sterling Heights, MI; 7/31/05 |
| A: |
I understand
that Florel can limit the production of cotton on
cottonwood trees. The timing of the application
is the key to its success, so read and follow
label instructions carefully. The product is
sprayed on the tree. Because the tree is "huge"
spraying may be a challenge. |
| |
|
| Q: |
We have a small Colorado blue spruce in our back yard that
we got as a seedling about 5 years ago. It's now about 3 feet tall &
we want to transplant it into the center of the yard where it will have more
room to spread out. We have somewhat sandy soil. It is okay to move
it this time of year? B. D., Colorado Springs, 7/4/05 |
| A: |
Summer is not a good time to transplant trees. Tree roots get
damaged in the process and have difficulty absorbing sufficient water for
the tree. If you don't mind waiting, spring is actually the best time
to transplant the tree. |
| |
|
| Q: |
We have had the trees in our mobile home park trimmed/deadwood
cut out, etc., and there are quite a few that have sap dripping from the cut
areas. What can we do to stop the dripping, etc? K., Albuquerque, NM;
6/20/05 |
| A: |
I am not aware of anything that can be done to stop the dripping sap.
Gradually the trees will form a protective barrier over the wounds and sap
flow should gradually cease. |
| |
|
| Q: |
I live in California and just bought a half acre in Leadville, Colorado.
What trees could I plant that with some TLC could survive at that high
altitude. Any size is ok. N. R., San Jose, CA; 5/22/05 |
| A: |
Some trees that grow at elevations up to 10,500 feet include
these:
Engelmann spruce (Picea engelmanni)
Bristlecone pine (Pinus aristata)
Limber pine (Pinus flexilis)
Subalpine fir (Abies lasiocarpa)
The growing period is very short at Leadville's altitude. The
trees should be planted as soon as the ground isn't frozen so the
roots can become established before the ground freezes again.
|
| |
|
| Q: |
Hello, I was wondering if you
could help me. My mother loves to garden and being the good daughter that I
am I would like to get her some trees. Unfortunately I don't have to a clue
to what would have the best survival rate for Pueblo West, CO. I was
wondering if the Norway Spruce, Colorado Blue Spruce or White Pine would be
good choices. They would probably be small seedlings. It can become very hot
and very windy in Pueblo West. There isn't much rainfall either. I'd really
appreciate any advice. Thanks! M. Lincoln, NE; 2/26/05 |
| A: |
Some trees that should do well
in Pueblo West include Pinon Pine (Pinus edulis), Austrian Pine
(Pinus nigra) and Bur Oak (Quercus macrocarpa). Colorado Blue
Spruce would also do well, but it requires more water than the
pines or oak. |
| |
|
| Q: |
I have an evergreen tree probably 40 ft high with a trunk
that is 1 1-2 ft round. It is starting to lose its needles from the
bottom up. It is getting pretty bad. What can I do to revive
this tree -- fertilizer spikes, tilling the ground, what? J. H.,
Horace, ND; 2/14/05
|
| A:
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Browning of evergreen needles and needle drop
can be caused by several things. Older needles on evergreen
trees turn brown in fall and drop. The species of the tree
determines just when this will occur. The inner needles are
mainly involved in this process. Too much moisture and poor
drainage can cause needles to brown and drop. A symptom of
this problem is that browning moves from bottom to top and from
the inside to the outer edges of the branches. Winter injury
due to desiccation can cause browning. Pests such as mites,
aphids, etc. can damage the tree. Inspect the tree with a
hand lens for these. Do not till the ground under the tree.
That would damage the tree's roots. Wait until spring to
fertilize the tree.
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| Q:
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Can you tell me what, if any,
kind of palm and banana trees are compatible with our Colorado conditions?
T. W., Aurora, 1/14/05
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I did a search on the
Internet to see if any palm or banana trees were suited to Zone 5. I
did not find any palm trees, but I did find information about a banana.
Japanese Fiber Banana (Musa basjoo) can grow in Zone 5 if protected.
It needs to be heavily mulched (One foot was suggested). A
south-facing spot near a structure such as a wall is a good site.
The fruit isn't edible. It is grown for its tropical appearance.
It is likely to die back in winter but will resprout in spring if mulched
well.
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| Q:
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I'm in Denver and have a living
Norwegian Pine. I've been given different advice about planting
it outside. Can you tell me if will it grow well in this climate or if
I should retain it as a house plant? K. C., Denver, 1/3/05
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The Norwegian Pine
can be planted outside -- but not now. Wait until spring to
plant it. Newly planted evergreens tend to dry out in
Colorado's winter weather and then die.
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| Q:
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I live in Grand Junction,
Colorado. A local landscaper stated that he can plant established
trees and shrubs well into the winter months of December and January.
Is this an acceptable time to plant these types of plants? Thank you.
R. W., Grand Junction, 12/7/04
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| A:
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Winter is not considered a good
time to plant in Colorado. Spring is the best time. Early fall
(until mid October) is considered the second best time to plant.
However, evergreens should not be planted in fall. The plants lose moisture
through their needles and their young root systems can't provide sufficient
moisture in winter.
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| Q:
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We have two magnificent weeping
willows around 70' high. These two trees are the focal points in
lovely garden areas but some pruning/topping problems have come up.
The trees were topped about ten years ago prior to our acquisition of the
property. As a result they branched. Last fall each tree lost 2
very large limbs. They were recently pruned up to 35' but we are now
wondering if they should be topped again and if that can be done without
further branching. Or, should we simply thin the upper areas? I
recently read an article that strongly recommended against tree topping.
We're particularly concerned about why both trees lost two large (24"
dia) limbs at about the same time. One particularly has a big gap in
the foliage that will probably take years to fill in. Your opinion on
the subject will be greatly appreciated. S. B., Fairfield, CA; 11/9/04
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As you have read,
topping trees is not recommended. It causes trees to
produce multiple new branches. Unfortunately, this new
growth often is weak and unnatural looking. In addition,
topped trees are prone to disease and insect problems due to the
many, large cuts. Thinning is much preferred.
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| Q:
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I live on the south side of
Colorado Springs and I really would love to grow a horse chestnut tree in my
front yard. I did some research on the particular kind of tree. I found out
that it likes clay soil. Since we are surrounded with it, it should do well
here. One the other side, I hardly ever see horse chestnut trees here.
Could you please tell me some more about it? Thank you. A. M.,
Colorado Springs, 9/30/04
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Common
horsechestnut (Aesculus hippocastanum) is a large tree that grows
50' high and 40' wide. It does well in full sun or part
shade. It prefers moist soil. It has white flowers in
spring and produces fruit, which can be a nuisance to clean
up. The roots can be invasive. It does perform well
here.
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Looking for recommendations for
a tree reddish in color that will grow in height 10 to 20 feet with 10 to 15
foot canopy. The tree location will be approx. 10-15 feet from the
front corner of the east side of the house and the same distance from
a stone walkway in the Denver Hilltop area. Can you provide a list of some
recommendations? J. H., Denver, 9/7/04
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Some small, reddish or
purple leafed trees include these:
Newport Plum (Prunus cerasifera 'Newport')
Mt. St. Helens Plum (Prunus cerasifera 'Mt. St. Helens')
Double-Flowering Plum (Prunus triloba)
Purple Prince Crabapple (Malus 'Purple Prince')
Royalty Crabapple (Malus 'Royalty')
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I would like to plant a European
Mountain Ash on the north side of a large blue spruce. If I am
prepared to take heroic measures in soil amendment--to make it more
well-drained and pH balanced--do I need to be concerned about which variety
will fare best? I prefer the Sorbus Aucuparia 'Cardinal Royal' because
of the berry color, but I've been told that 'Black Hawk' is hardier and more
sun scald resistant. Would that mean 'Black Hawk' is more fire blight
resistant, also? Thanks! J. M., Fort Collins, 9/4/04
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European Mountain Ash
(Sorbus aucuparia) needs well-drained soil and prefers acid soil, so
you will need to prepare the planting site well. This type of
tree is very prone to problems such as canker and borer when
stressed. Compacted soil, heavy clay soil and alkaline soil
will stress it. Black Hawk is more resistant to sun-scald.
Sun-scald wounds stress a tree, making it more susceptible to pests
and diseases, including fire blight. Therefore, it might be a
better choice.
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We live in Aberdeen, S. D.
Four years ago the county extension planted a tree claim of lilac bushes,
which are doing great, and cottonless cottonwoods. We transplanted them 2
years ago and this year we lost over half of them (transplanted 30). Now we
have about the same amount of evergreens to move but we don't know the best
time to move them. Could you give us some advice? M. M., Aberdeen, S.
D.; 7/21/04
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Early spring is
the best time to transplant evergreens. Do not move them
in fall. The root systems, which are disturbed/damaged
during moving, can't supply enough moisture during winter
and they will dry out too much. By spring they would
begin to die off. During the hot days of summer is also
a poor time to move them for the same reason.
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| Q:
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How do I properly prune scotch
pine trees? They are currently in the candlestick phase. R.,
Greeley, 5/29/04
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To prune pine trees, snap
off a portion of the candles - usually about a third or half of the
candle. Snapping them off, rather than cutting them off with pruners,
is advised to prevent edges from browning.
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I have a newly planted Ponderosa
Pine, approximately 12 ft. tall. on an elevated berm, approximately 24."
It was planted last fall, and I do have it on a drip system. It also
gets a little overflow from the grass sprinkler. I am getting some
yellowing. Any ideas? I did give it a root stimulator early in
the spring. B. F., Loveland, 5/8/04
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Too much or too little
watering can cause yellowing, so it can be tricky to determine if you
need to water more or less. If you did not water the tree during
winter, it may be showing the effects of too little water. The
root system of an evergreen tree that is planted in the fall often
struggles to meet the tree's water needs in winter.
If you have been
running your sprinklers and the tree is just starting to yellow, it
may be getting too much water -- especially since it is on a drip
system and gets water from the grass sprinkler. Pines need good
drainage and only a limited amount of water once they are established
(about a year after planting). You may need to adjust the amount
of water the tree gets from your irrigation system.
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Yikes! We live at 8,600
feet just outside of Mancos, CO. We shift from drought to snow in
the blink of an eye - well maybe from year to year. We have fields
full of pinion, some cedars, Ponderosa Pine, and have had a little success
cultivating aspens. But my wife misses her big flowering trees.
Are there any medium to larger flowering trees that would survive the
summers and winters in this high sunshine, sometimes moist, sometimes
heavy snow area? G. Mancos, 4/28/04
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Unfortunately, the lists of
trees for high elevations I have available do not include any flowering
trees for elevations above 8500 feet. With protection -- and luck
-- apple trees such as 'Lodi' or 'Haralson,' some crabapples and Shubert
Chokecherry (Prunus virginiana 'Shubert') might survive. They are
listed as hardy to 8500 feet.
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Just wanted to get some
recommendations for a small tree to fill a spot in my backyard. I
already have a Austrian pine about 25 ft. tall and I would like something
colorful to compliment it. PS - I don't want anything that has fruit
on it. Thanks A. J., Loveland, 4/20/04
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The following are some small
trees that would be colorful during some seasons:
Cleveland Select Callery Pear (Pyrus
calleryana 'Cleveland Select') -- This tree is non-fruiting, has white
blossoms in spring and has fall color.
Spring Snow Flowering Crabapple (Malus 'Spring
Snow') -- This tree is non-fruiting and has white flowers. It has
some fall color.
Newport Plum (Prunus x cerasifera 'Newport')
-- This tree has pink flowers, purple foliage and little, if any, fruit.
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What location considerations
would you use if you wanted to plant an eastern red bud tree and Japanese
maple in our climate? Are there any species that are more hardy in
Colorado. Live in Brighton. B. T., Brighton, 4/19/04
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Eastern Redbud (Cercis
canadensis) trees perform best in full sun, although they tolerate
partial shade. A spot sheltered by structures or other plants is
preferred. They require good drainage. Therefore, you
should amend the soil with compost before planting. Avoid using
products containing cow manure because the high level of salt will
damage the tree. Eastern Redbud trees prefer moist, but not
soggy, soil.
Japanese Maple (Acer
palmatum) trees require filtered shade. A northern or eastern
exposure is best. They need shelter provided by structures or
other plants. They like moist, well-drained soil and are harmed
by high levels of salt in the soil. Hardiness can be a problem
here. Unfortunately, I am not familiar with which species of
these trees are most hardy. Be sure to check plant labels for
this information when shopping.
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| Q:
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Can we grow Magnolia Trees in
Lakewood, Colorado? K. B., Thornton, 3/31/04
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There are some types of
Magnolia trees/shrubs that can be grown in Colorado, but they are not
the large, stately trees associated with the South and other warm
climate areas. They require a sheltered location, away from wind
and sun. An eastern exposure works well. They like moist,
well-drained soil and may have problems in heavy clay soil. Late
spring snow and spring frosts may damage flowers. Some types for
Colorado include these:
Saucer Magnolia (Magnolia
x soulangiana) 15 - 20 ft. tall
Star Magnolia (M.
stellata) 10 - 15 ft. tall
Hybrid Magnolia (M. x
loebneri) 15 - 20 ft. tall. Look for 'Ballerina,' 'Merrill' or
'Leonard Messel.'
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| Q:
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I live in zone 6. We have
a 20+ year old corkscrew willow. Some of the branches did not get
leaves last summer and appeared dead. We have not trimmed/pruned this
tree that I know of -- ever. How and when do we do this?
It is a beautiful tree and it breaks our hearts to think we could lose it.
Thank you, D. L., Gardnerville, NV; 3/7/04
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Unfortunately, corkscrew
willow trees are short-lived. Try to keep the tree as healthy
as possible by providing plenty of water. Check the branches
carefully for signs of pests that could cause the tree to decline in
health. Prune off dead branches. Hopefully it will last a bit
longer.
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I planted a bristlecone pine in
my front yard two years ago (south facing, full sun). In general, the
tree seems healthy with a few inches of new growth each year; however, the
ends of the bottom branches are browning and dying. I've examined the
soil under the tree and it always seems moist, but it also seems like the
tree likes to be watered from the top during the summer -- this seems to
slow/recover some of the brownish needles. I think that the soil is
wet enough, but all signs point to the tree wanting more water. Is the
full sun too much for the tree regardless of the watering frequency?
C. H., Fort Collins, 2/18/04
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Bristlecone pines require full sun,
so the amount of sunlight is not causing the browning. This tree does
best in well-drained soil. If the soil is constantly moist the tree
will probably die. The tree should be watered deeply. Apply
water throughout the root zone -- a distance equivalent to the height of the
tree, as a minimum. Then, allow the soil to dry out before
watering it again. Hose off the tree with a jet of water to remove
dust and pests periodically.
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I planted a blue spruce in May
2002 and it survived the drought pretty much intact. However, the tips
of some branches throughout are bare and brown. I deep root watered
two weeks ago. Is the tree indicating the need for additional
water? How often should it be watered? Any advice is
appreciated. thank you. C. F., Denver, 10/16/03
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During spring, summer and fall
you should provide about 10 gallons of water per inch of the tree trunk's
diameter weekly. For example, if the trunk is two inches in diameter
the tree should receive twenty gallons of water. Be sure to water
the tree occasionally during winter if we get little snow. Water
early in the day when the ground isn't frozen. There also are
sprays, such as Wilt-pruf, that can help the tree to retain moisture
during winter.
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I have a very large tree in my back yard, and I am not sure
if it is an oak or maple. My question is: Why would it be loosing
its leaves already? Every time we get a wind or wind gust it drops
more leaves. Can you help? L. W., Lakewood, 7/1/03
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Leaf drop can be caused by a number of things. Be sure
that the tree is getting plenty of water. Damage from the drought is
a possible factor, especially with large trees. Trees under stress
from disease, insects or other unfavorable conditions sometimes drop their
leaves. Some trees will drop leaves as newer growth shades older,
interior branches.
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| Q:
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I planted a corkscrew willow this spring. Why now, 2 months
later, is it losing it's leaves during our first hot spell? It get
regular watering and looked fine until this hot spell. R. R., The
Dalles, Oregon; 7/1/03
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Often the root system of newly planted trees cannot
adequately provide the moisture needed in hot weather. Continue to
water the tree regularly. Willows like plenty of water. Also,
spray the tree with water on hot days to provide additional moisture.
Do not fertilize the tree. You don't want to encourage canopy growth
while the root structure is limited in size and vigor.
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I live in Woodland Hills, Utah, at 6,000ft elevation. I have Aspen
trees in the front yard that are beginning to block the view of the valley
below. They start blocking the view when they get about 15-20 feet
high. What is the correct method to "top off" the trees without
hurting them or making them look like they've been hacked off? Thank you.
R. P., Woodland Hills, UT; 5/27/03
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Unfortunately trees cannot be topped off without hurting them or making
them look like they've been hacked off. There are two ways you can
try to maintain some of the view. You can thin the canopy of the
trees by removing some of the branches. Also, you can remove some of
the trees.
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| Q:
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Can you tell me if a Cleveland Pear would be a good tree for my front yard
space of about 20 ft. wide? Also is it susceptible to fire blight or other
diseases? V. V., Boulder, 5/21/03
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Cleveland Pear would probably be
a good tree for your front yard. This tree, which is also known as
Chanticleer Pear, grows to a height of 25 - 30 feet and a width of about
20 feet. It requires full sun. It is resistant to fire blight
and other diseases and pests.
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| Q:
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We are planning to install a drip or mini-spray irrigation system in an
area that contains several established Aspen trees. The
"outlets" for these systems, as I understand it, are available
in terms of gallons per hour. What are your recommendations for the
weekly water requirements for Aspens in these terms here in Colorado
Springs? Thank you for any assistance you may be able to provide.
R. B., Colorado Springs, 5/9/03
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Recent guidelines recommend the
following watering schedule for April through September for established
trees.
Small trees (1 - 3" diameter):
10 gallons per inch of trunk diameter weekly
Medium trees (4 - 8" diameter):
10 gallons per inch of trunk diameter three times per month
Large trees (9" diameter and
up): 15 gallons per inch of trunk diameter twice per month.
Keep in mind that a tree's root system spreads out to a width
that is 2 - 3 times wider than the tree's height. Water should be
applied throughout this zone, not just around the trunk. You can
reduce the amount of water applied by the drip system if the trees receive
water from other sources such as the lawn sprinkler.
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| Q:
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Hi, We have an emerald green arborvitae. It was planted last year. During
the winter, the tree was getting brown and now is better. But still the
edges of the leaves are brown. We asked some people. Some told us it was
burnt by the afternoon sun; some said we watered it too much. The tree is
facing South. We watered it once/month in winter, and twice/week now.
Should we move the tree?
Also, our tree is not growing upwards, the top of the tree looks like it's
spread out, and could not hold itself up. How should we prune it? Thanks.
V., Longmont, 5/6/03
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| A:
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Arborvitae trees and shrubs need
shade or partial shade (no afternoon sun). You should move it from
its current south-facing location. They are easily burned by the sun
and dry winds, especially during winter. They prefer plenty of
water. You were wise to water your tree once a month during winter.
The top of the tree probably sustained damage from heavy snows. I
suggest that you wait at least a month to see if the branches return to a
more upright position rather than pruning them. You might also try
tying them into place temporarily next winter to avoid snow damage.
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| Q:
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I am searching for a good type of tree for my area. Something
sturdy, semi-fast growing and disease resistant. K.,
Englewood, 3/11/03
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| A:
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Some popular shade trees include
these:
Green Ash (Fraxinus pennsylvanica) -
may have problems with ash sawfly or ash-lilac borer; does well in drier
conditions
Hackberry (Celtis occidentalis) -
very drought resistant, may get harmless small bumps on the leaves called
nipple gall
Littleleaf Linden (Tilia cordata) 'Greenspire'
or 'Glenleven' - attracts bees when in bloom, must protect trunk from
sunscald in winter, likes regular watering
Norway Maple (Acer platanoides)
'Deborah' or 'Emerald Queen' - likes regular watering.
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| Q:
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I have a seventy foot white
alder tree in my back yard. What is the best way to trim it? I know
it is to be trimmed in the summer. Can I top the tree and take off forty
feet? J. R., Elk Grove, CA; 1/26/03
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| A:
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Trees that lose their leaves
(deciduous trees) may be pruned in late winter or early spring when the
tree is almost ready to leaf out or in midsummer after growth has slowed.
Topping trees is not recommended because it weakens the tree and can even
shorten its life. Instead, the crown should be thinned by removing
selected branches. Good candidates for removal are branches with
narrow, V-shaped crotches, weak and dead branches, branches that interfere
with or rub against others, and ones that are growing too low, too close
to structures, etc. No more than one third of the branches should be
removed annually. Trimming a tree of this size can be dangerous, and
if it is not done properly can result in serious health problems for the
tree. You might want to look into hiring a reputable tree service
for such a major task.
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| Q:
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I have some evergreen trees
that I need to trim down. When is the best time of year to do this?
I live in Northern Indiana. Thank you for advising. C. C.,
Merrillville, IN; 2/3/03
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Pine, spruce and fir trees can be
pruned in early spring.
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| Q:
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How much and how often do I need to deep root water my trees and bushes
considering the current drought conditions in Colorado. I am mostly concerned about a 50 ft elm, and 3 twenty foot crabapples, and
2 15 to 20 ft pine trees. I also have around 10 aspens in the 10 to
20 ft range. B. W., Aurora, 1/14/03
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| A:
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During the winter months you should water once or twice a month if there
has been little or no snow. Water when the temperature is above
freezing and the soil isn't frozen. Try to water early in the day so
the water can soak in or evaporate before nightfall when temperatures
drop. This will prevent water that collected in cracks and crevices
of tree trunks from freezing and damaging the trunks. To determine
how much water a tree needs measure the diameter of the tree's trunk in
inches. Apply approximately ten gallons of water per inch in
diameter. Be sure to water the entire root zone area, not just by
the trunk. The root zone extends to a width that is about twice the
height of the tree, or more.
Water established shrubs once or twice a month also, depending on weather
conditions. Small shrubs (3 feet tall or smaller) should get about
five gallons of water. Medium-sized shrubs should receive about ten
gallons. Large shrubs (over six feet tall) should get between 15-20
gallons of water. As with trees, direct the water throughout the
root zone, not just at the trunk. For additional information, please
see www.watersaver.org.
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| Q:
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Hi!
I've got a small Norwegian Pine which seems to have been
insufficiently watered. I have given it the water it needs and kept its
pot in a window for light. I noticed small bugs in the soil. I also know
what to do for these. However, the needles on certain parts of the tree
have fallen. Some entire branches have even snapped off. This tree has
four trunks, each smaller than the next. The biggest trunk is the one that's
seemed to do the worst. I am wondering if I can carefully cut this trunk
down altogether and whether the remaining three trunks would do well.
I'm
also hoping to one day plant this Norwegian Pine outdoors. Will it do well
here in SE Lower Michigan? Our soil is almost all clay, and the weather
is very unpredictable in ALL its seasons. For now, I just want the tree to
be healthy. What should I do NOW??? Thanks. L. A., Gibraltar,
MI; 1/4/03
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| A:
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You may prune off any areas of your Norwegian Pine that you feel should be
removed. A good guideline when pruning is to remove no more than one
third of the plant per year. Whether the remaining sections of the tree will do well is
hard to predict. If you corrected the watering problem soon enough,
can control the bugs in the soil, and can provide a suitable environment,
the tree hopefully will survive. Provide sufficient water, but be
careful not to over-water the tree. Yellowing needles are a sign of
too much water. Be sure the tree gets ample sunlight while in the
house. It will also need a sunny spot when you move it outside.
You live in USDA Hardiness Zone 6, so it should do fine outside. A
potential problem is the clay soil. Pines require good drainage.
Try to select a site that is high. If your property is flat, you may
want to build up a berm to plant it in. Amending the soil with
compost will also promote drainage. Good luck.
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| Q:
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Hello, I could use some advice. I
just bought 2 acres near Fairplay (same elevation) and want to plant some
conifers as a wind break/food source for native animals on it. They
would get the north wind and will be fairly close to a stand of aspens, to
their south. When is the best time to plant these trees also?
Thank you very much. K. C., Denver, 11/11/02
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| A:
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Due to the high elevation of Fairplay
and the surrounding area, probably the best conifer to use as a windbreak
is limber pine (Pinus flexilis). While several other trees would be
good windbreaks, they wouldn't survive at such a high elevation (about
9900 ft.). You might want to plant some shrubs that have berries for
wildlife next to the trees as part of the windbreak. Some shrubs
that are hardy to 10,000 feet include Serviceberry (Amelanchier alnifolia),
Peking Cotoneaster (Cotoneaster acutifolius), American Elder (Sambucus
canadensis), and Canada Buffaloberry (Sheperdia canadensis). The
best time to plant these trees and shrubs is in spring once the ground
isn't frozen. Good luck with gardening at this elevation. It
will be a challenge!
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| Q:
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I have several smaller Blue Spruce
trees that have been doing very very well...until now. They each have
(had) at least 6 inches of new growth on them, but suddenly they all
started to droop from the top down. I have been very careful to keep them
watered - at least I thought I had...Of course I'm thinking 'drought', but
I'm wondering at what point it's too late to save them...and it the
drooped part will come back if I water more...?? Thanks! C.
P., Colorado Springs, 6/28/02
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| A:
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Drooping from the top down and outside
in can be a sign of insufficient water. Be sure to water the entire
root zone, not just the area by the trunk. Deep watering rather than
frequent shallow watering is preferred. Check the moisture level
frequently by digging down with a small hand shovel. Evergreen trees
require winter watering. If the trees didn't receive sufficient
water in winter they will appear fine in spring and then die when the
weather warms up.
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| Q:
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I just had a young crabapple tree planted a couple days ago.
My landscaper friend and I picked it out at a nursery in Parker. Its
leaves were wilting at the very top on many of the branches and have since
died. The landscaper called it wind burn and also mentioned that the
top of the root ball might not have been wrapped as high as it should have
been. I've been told two conflicting things: 1) trim the dead
tops off now and 2)leave them alone because it's best to do it in the
winter AND because a second growth could still happen this summer.
Advice? Thanks! L. S., Denver, 6/13/02
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| A:
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Do not trim the crabapple tree now.
With sufficient water some of the branches may leaf out again. When
in doubt, I always prefer to give a plant a chance to recuperate before
chopping off parts that may still be healthy! More importantly,
crabapple trees are very susceptible to a disease called fire blight.
Disease organisms can enter the tree through wounds and cuts. Warm
and/or rainy weather promote the spread of this disease. Therefore,
these trees are pruned in late winter or early spring while they are
dormant and the weather is cold.
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Our elms, both Siberian and American, have extensive leaf drop this
year. Leaves all or partially brown out prior to dropping.
When examined on the tree, there is a black, sort of kinky, material
inside the leaf. Looks like an insect of some kind but have not seen
larva or eggs. Believe we had this last year, but much worse now.
Thought it might be Elm Leaf Beetle, but the leaves are not lacy, or
chewed through. T. H., Lakewood/ 6/9/02
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Without seeing a sample, it is
difficult for me to determine what the problem may be with the elm trees.
Some possibilities include insects -- if the black, kinky material is
droppings, sooty mold, or spiny elm caterpillars. I suggest that you
take a sample to your county CSU Cooperative Extension office or to a
garden center that has staff who can diagnose exactly what the black
material is and then advise you regarding treatment. Due to the
value of established trees in the landscape, I suggest you do this soon.
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Hello, are there any very small trees or shrubs that could survive
year round in a container on my partial-shade, covered patio? And do
you have any suggestions for the same type of thing, that could easily be
moved indoors for the winter season? K. S., Greeley, 6/2/02
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It is extremely difficult to
over-winter trees and shrubs planted in containers here. The soil
and root ball will freeze, preventing the plant from absorbing water.
Our drying winds compound the problem. The freeze/thaw cycles in
spring are also quite damaging. I encourage you to invest in plants
that can be used outdoors while the weather is nice, and then be moved
indoors.
I have a few suggestions regarding moving the plants indoors.
Before bringing the plants inside, hose them off to remove dust and pests.
Remove any dead leaves, flowers or other debris from the top of the soil
or on the plant. Choose a spot in the house that has bright light (a
western or southern exposure). You may want to keep a lamp on in the
evening for a few hours to provide additional light for the plants.
Water the plants as needed, being careful not to over-water.
Some plants to consider include Azalea, Bougainvillea, dwarf citrus
trees, Ficus trees, Geraniums, Hibiscus, Hydrangea, as well as many
others. If the plants have been kept indoors at the garden center,
you may need to put them outside for only a few hours each day, gradually
increasing the time spent outdoors.
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We planted a Linden tree about two months ago. The leaves just came
out 2-3 weeks ago. The leaves now look "limp" or
"wilted." We checked the soil about 3-4" down and it
is damp. Does it need more/less water or what could cause the
wilting? We received snow & cold weather 4 days ago. Thank you.
D. K., Castle Rock, 5/27/02
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| A:
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It is very likely that the cold weather
was a factor in causing the leaves of the linden tree to wilt. If
the soil is moist, do not apply more water. Too much water
suffocates plants, resulting in wilted leaves and eventually death.
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I live in Midwestern Wisconsin and was
wondering what the advantages/disadvantages of planting a Tulip Poplar in my
backyard with full sun are. Any information you could give me would be
appreciated. Thanks. L. A., Chippewa Falls, Wis.; 5/11/02
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I found the following information about
the Tulip Poplar tree (Liriodendron tulipifera). I hope you will find
it helpful.
The Tulip Poplar tree needs moist, rich, well-drained soil. The
pH of the soil should be neutral to slightly acid. It requires full
sun and regular water. A fast-growing tree, it can reach a height of
60 - 80 feet and a width of 40 feet. Thus, it is a good shade tree in
yards that have sufficient space. If space is a problem a
slower-growing, smaller cultivar such as Columnar 'Arnold' ('Fastigiata') or
'Aureomarginatum' ('Majestic Beauty') might be a better choice. Found
in the eastern U. S., this tree grows well in USDA hardiness zones 5 - 9
(and possibly zone 4). The tree usually does not bloom until it is
several (12 or more) years old. In addition to the flowers, the tree
is liked for its fall color. The tree may be difficult to get
established. Also, it may be hard to garden under the tree due to its
shallow root system.
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We are moving to Ridgway, Co. I
can't find a plant hardiness map that shows Ouray County large enough for me
to determine what our hardiness zone is. What plants would you
suggest. We have a south sloping lot with mostly pinyon pines and a
few types, but not ponderosa or Aspens. When we are living there, we
plan to plant some Aspens. Do you recommend this? Thanks.
N. B., Davison, MI; 5/3/02
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| A:
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Your hardiness zone appears to be Zone 4
or Zone 5. Aspen trees are frequently planted in both of these zones,
although they are best suited to the mountains. Given the frequency of
drought conditions in Colorado in recent years, I'd encourage you to plant
shrubs and perennials that do not require a lot of water. Limit the
amount of lawn because it needs lots of water -- as well as regular
applications of fertilizer, mowing, edging, weeding, etc.
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How do I take care of a weeping
pussy willow tree in Colorado? J. O., Littleton, 4/17/02
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| A:
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Weeping Willow trees and Pussy
Willow trees and shrubs like lots of water. They usually can tolerate
poorly drained soil. They are prone to problems with insects such as
aphid and scale. Inspect them frequently for pests and take action
promptly if pests are found. Willows are fast growers, but
unfortunately they do not live very long.
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I live in Colorado Springs.
I am removing an old Russian Olive tree from my front yard. I would
like to know what type or types of tree I can plant in its place. My
house faces west and receives quite a bit of sunlight. The soil is
clay. What would you recommend? D. V., Colorado Springs, 3/21/02
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| A:
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If you want a shade tree you might
consider these:
White Ash (Fraxinus americana) 'Autumn
Purple'
Green Ash (Fraxinus pennsylvanica)
'Marshall's Seedless' or 'Patmore'
Littleleaf Linden (Tilia cordata) 'Glenleven'
or 'Greenspire'
Norway Maple (Acer platanoides)
'Deborah' or 'Emerald Queen'
Be sure to consider how high and wide the tree will be at maturity when
selecting a tree. You didn't mention how much space you have for the
new tree, but because your house faces west and gets afternoon sun I assumed
you would want a shade tree. Some nice, smaller ornamental trees are
available if the yard is small:
Thinleaf Mountain Alder (Alnus
tenuifolia)
Birch (Betula) -- several types are
available
Hawthorn (Crataegus) -- several types
are available, such as Washington (C. phaenopyrum), Cockspur (C. crusgalli)
and Russian (C. ambigua). Most have thorns.
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In Y2000, I purchased 2 Dwarf
Alberta Spruce (Picea glauca "Conica") from a local nursery. I
planted each tree in a large 1-inch thick foam pot located in a semi-sunny
and wind-sheltered location in my fenced patio. Trees were watered regularly
when top-soil seemed dry and fertilized 2x yearly with appropriate evergreen
fertilizer. In the first year, one tree browned-out and died, first dropping
its needles from near the trunk progressing out to the branch tips. This
year, the second tree is following the same brown-out pattern. Thinking
perhaps there was an unseen pest on the trees, they were sprayed twice
yearly with insecticidal soap solution.
Why am I losing these expensive trees even though they have
received constant attention and care?
As a substitute for dwarf Alberta Spruce, are there any potted
specimens of upright juniper or yew which might be acceptable patio
applications (8 ft. maximum height)? Thank you. C. H., Lafayette,
3/3/02
Follow-up question:
On Mar. 16, you were kind enough to give me some valuable
suggestions regarding my project to grow upright junipers in pots. Thank you
for your inputs.
As an alternative to small upright junipers in pots, what do
you think about growing the following in pots:
Emerald Green Arborvitae, Thuja
occidentalis "Smaragd'
I would appreciate your thoughts on this species. Thanks. 3/20/02
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| A:
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Growing trees and shrubs in containers is
not easy in Colorado. The biggest challenge is to provide the right
amount of water. If the plant is over-watered it will die, so good
drainage is essential. The pots should have drain holes. If the
pots ever dried out completely, that may have caused the plants to die, even
if they showed no symptoms immediately and were later watered well. A
soil moisture meter like the ones used for houseplants would be helpful for
determining when to water the containers. Unfortunately, even when
watered properly, evergreen trees and shrubs such as Alberta Spruce tend to
dry out in Colorado's excessively dry climate due to loss of moisture
through the needles. The root system can't replace the lost moisture fast
enough. In winter it helps to spray evergreen plants with Wilt-pruf to
prevent moisture loss.
Another problem with plants in containers is temperature.
In summer the soil is likely to heat up excessively and in winter it is
likely to get too cold. Because pots often don't provide enough
insulation, the plants are at risk. The larger the pot, the better the
chance for survival. One source I consulted recommended pots with a
minimum depth of two feet and a minimum diameter of 24 - 30 inches.
Unless you actually see signs that a pest is present, I suggest
that you avoid using pesticides -- even milder ones like insecticidal soap.
Some plants are sensitive to pesticides. Instead, spray the tree with
a strong jet of water.
Plants in containers do require more fertilization than those
planted in the ground. The frequent watering that container plants
require leaches, or washes out, the minerals in the soil. Diluted
solutions applied more frequently would reduce the chance for fertilizer
burn and keep soil mineral levels more consistent.
There are a few upright junipers you might consider for your
containers: Chinese Juniper (Juniperus chinensis) 'Blue Point,' Rocky
Mountain Juniper (Juniperus scopulorum) 'Medora' and Rocky Mountain Juniper
(Juniperus scopulorum) 'Gray Gleam.' Yews aren't the best choice for
containers here. They tend to be finicky. I wish you luck.
Response to follow-up question:
Arborvitae, like yew and Dwarf Alberta Spruce, is a risk.
All require afternoon shade, protection from the wind, and winter
protection. Instead of upright junipers you might like a dwarf pine:
Scotch Pine (Pinus sylvestris) 'Nana'
or 'Fastigiata'
Tanyosho Pine (Pinus densiflora) 'Umbraculifera'
&nbs |
