Questions?
E-Mail
Forestry Division
If
possible, take a couple of digital photos of your tree or shrub
and include them with your questions. One photo should be a close
up of the problem area. The second photo should be of the entire
tree if possible.
Allergies
and Trees
In the spring,
most trees flower and produce pollen. Trees that produce colorful,
scented flowers are usually pollinated by insects or birds and
less by wind. Trees that do not produce colorful,
scented flowers are primarily pollinated by wind. Some wind pollinated
trees have the female fruit/seed structure and the male pollen
structures on the same tree. Other wind pollinated trees may have
a female tree that only produces a fruit/seed and a separate male
tree that only produces the male structure bearing pollen. Tree
pollen can be around in Cheyenne as early as late February through
late summer.
People can
be allergic to any type of pollen. The most common pollen that
causes allergies is the wind-borne pollen from trees, weeds, and
grasses. Additional information on pollen and allergies: Additional
Info.
Visit a lake
in a conifer tree (e.g. pine, spruce, fir, juniper) forest in
late May to early June and you will see a yellow "ring"
around the lake shore or a yellowish film on the surface of the
water near the shore. This yellow ring and film is pollen from
the conifer trees. During the last month of spring, you can also
see a yellow dust cloud of pollen around the conifer trees during
a wind gust.
Maple
Trees "Bleeding" Sap
In late winter and early spring, as sunlight increases
and days become warmer, with the nights still below freezing,
the sap in maple trees begins to move. In late winter and early
spring, maple syrup producers tap sugar maples to collect the
sap to boil down to make maple syrup. All maple trees have
a sugary sap flow. The Norway, silver, Amur, and boxelder
maples in Cheyenne also have a high sap flow this time of year.
If the tree has been recently pruned, or there is squirrel
damage on the limbs or trunk, or the bark has been injured in
any way, sap flow will be present on the outside of the tree.
The outside "bleeding" itself is unsightly and may attract
insects, but it does not harm the tree. It is best to prune
maples in the summer when they are in full leaf to avoid the bleeding
of sap.
 
Sap "Bleeding" on the
outside of boxelder maple trees.
Note the fly in the bottom photo feeding on the sugary sap.
Brown Needles
and Foliage on Evergreen (Conifers)
If you have browning or dead foliage on your juniper,
spruce, or pine it could be drought damage. Evergreens need
water year round to maintain their leaves. Ample water in
mid to late fall is critical for evergreens to survive the winter.
If the winter is dry, watering during the winter is also
needed. The large, established evergreens can usually support
themselves without additional watering during the winter for normal
precipitation years. During years with below normal precipitation,
additional water should be provided to even the largest evergreens.
Younger and recently planted evergreens will need watering
throughout the year to maintain the leaves and reestablish a root
system. Often the north and/or west side of an evergreen
may have brown foliage while the rest of the tree or shrub is
green. Direct sunlight in winter can also dry out the south
side of evergreens as well. The common north and west winds
in Cheyenne during the winter months can quickly dry out the foliage.
If the soil around the shallow roots on the tree or shrub
is frozen or dry, the plant can't take in water to replace water
lost to dry winds. Watering Information: Click
Here.
Frequently, brown foliage can also indicate salt
damage or herbicide damage on the tree or shrub. If salt is used
on the sidewalk or road to melt ice, the salt can get into the
soil and kill nearby roots. Herbicides used on lawns to control
weeds can drift onto trees and shrubs killing the foliage or sometimes
the entire plant. Herbicide residue can accumulate in the soil
and affect the root system. Use caution when applying ice melting
products on sidewalks or roads near trees. Eliminate or reduce
the application of herbicides near trees and shrubs.
Watch for new growth to emerge on evergreen limbs
that currently have brown foliage. If no new growth emerges this
spring on the brown foliage limbs, they should be pruned back
to either the trunk or back to living foliage. Apply an adequate
amount of water to the shrub or tree this year to help it regain
its health. Applying water to the point of saturating the soil
for a long period of time can kill roots as easy as not applying
enough water.
A good thorough watering allowing at least one
inch of water, natural precipitation and/or tap water, to be applied
around the tree or shrub every 7 days should be enough water.
Be sure to water the tree or shrub at the drip line and beyond.
Most of the water absorbing roots are in the area around the drip
line and beyond. The drip line is the area on the ground directly
below the outer extent of the foliage. Trees and shrubs existing
in a grass lawn area will occasionally need additional water beyond
what the lawn receives. A watering regime for a tree or shrub
is infrequently for a long duration. A watering regime for
a lawn is frequently for a short duration.
Occasionally, diseases and insect problems can
be associated with limbs containing dead or dying foliage, but
trees and shrubs with insect and disease problems, were usually
under some environmental stress prior to the disease or insect
problem. p
Plan Now for Spring Tree Plantings
Planting trees in Cheyenne should
start with planning during the winter months by drawing a landscape
to scale of your lot. Then plan what to buy and where you
will place the tree(s) in the landscape. It is important
to find out the mature size of the plants you purchase and place
them accordingly so they do not outgrow the spaces that are provided
for them or do not become overcrowded. Locate underground
utilities by calling One Call of Wyoming at 1-800-849-2476.
Marking the location of underground utilities is required
by law prior to digging, and the service is free. Look above
the planting site to make sure a large tree is not placed under
electrical wires. Trees planted close to buildings, driveways,
sidewalks or curbs will cause future buckling problems as the
roots grow in diameter. Check with the city forestry division
for any ordinances that may apply to your landscape such as corner
property traffic visibility requirements.
Spring is usually the best time to plant your trees. Trees
planted at this time can take advantage of the spring rains, establish
new roots, and store enough nutrients to better survive the winter
months. Well established "container grown" or " balled and
burlap" trees enable planting time to be extended later into the
growing season.
When purchasing a tree make sure the main "leader" is not broken
and that your tree only has one leader. (Fruit trees like
apple or plum will have more than one leader so it is easier to
harvest the fruit and the branch structure can support the weight
of the fruit.) Check the trunk so the bark is intact and
is not damaged. Container grown trees should have an extensive
root system in which the soil adheres to the roots. Balled
and burlap (B&B) trees also should have a solid root ball that
is not broken or loose. Never carry these trees by the trunk,
which will loosen the root ball and break roots.
After purchasing your trees protect them from direct sunlight
and wind. Plant them as soon as possible. Bare root
trees can be soaked overnight and stored out of direct sunlight
. The trees should be planted at the same depth that they
grew at the nursery. Look for a soil stain on the trunk
of bare root trees which will indicate the depth the tree was
planted at the nursery. On a B&B tree remove the
soil around the trunk, the top part of the rootball to find the
actual location of the top roots. The top root growing out
of a swollen area on the trunk (root flair) is the planting depth
mark level with the surrounding ground level. The root flair
roots can be planted 3 inches above the surround ground level
to no more than level with the surround ground level. Planting
with the root flair above ground will allow for soil settling. The
width of the planting hole should be a minimum of 3 times the
diameter of the rootball. See this
planting illustration.
Bare Root Trees: Cut and remove broken roots before planting.
Hold the tree in place at the proper height and sift dirt
into the hole. Do not use large clods or chunks of sod to
fill the hole. Build up a rim of soil around the hole to
form a basin (soil ring) for future watering. Water trees thoroughly,
about an inch of water per week, depending on the rainfall. You
may need to stake the tree upright for one to two years.
Container Trees: Dig the planting hole much wider but no deeper
than the container. Carefully remove the container so the
soil and the roots come out together. Sometimes it helps
to cut the container up the side which allows the root ball to
slide out easier. If the roots at the base of the plant
have started circling straighten them out or cut them cleanly
off before planting. Proceed to plant as described above
under bare root trees.
Balled and Burlap Trees: Once the tree is at the site, remove
the lower 1/3 of the wire basket and burlap with bolt or wire
cutters and a sharp knife, if the soil ball is firm, before placing
the tree into the planting hole. Carefully lower the tree
into the hole with the aid of hay hooks secured under the remaining
top wires to lift the tree into the hole. (Remember you
purchased a B&B tree and you want the roots and soil to stay in
contact, so try not to drop or break the soil ball). The
tree may also be rolled carefully into the hole, taking care not
to drop the tree. Once the tree is in the hole it should
be straightened. Place and pack soil around the base to
help stabilize the tree and to keep the root ball together. Remove
the remaining wire basket, any twine and as much of the burlap
that you can without disturbing the root ball. Most Critical
Point: The tree should not be planted any deeper in the soil
than the root flair. Proceed to plant the tree as described
above under the bare root section.
Once planted and the soil rings have been made, add about 2-3
inches of mulch inside the soil ring to aid in keeping the soil
cool, conserve water, reduce grass competition and to keep trimmers
and lawn mowers away from the trunk. Stake the tree only
if the tree is in a windy area, if the root ball fell apart when
planting, or if it is a dense evergreen . Two stakes driven
into the ground on the outside of the soil ring should be sufficient.
Use one to two inch cloth straps with grommets in each end
to go around the trunk of the tree. Run wire from the grommets
in the straps to the stakes and tie. The wire should be
loose to allow the tree to gently move in the wind. Remove
the stakes the following year.
After the initial watering whenever the ground becomes dry in
the top two inches soak the area under the tree crown thoroughly.
Apply at least 10 gallons of water in the area under the
tree crown for every one inch of tree trunk diameter. In
sandier soils and windy areas you will have to water more often.
Avoid light, frequent watering which will encourage only
shallow roots to grow. Normal lawn watering usually does
not provide adequate water to newly planted trees.
After the tree is growing, you can keep it healthy by following
these guidelines:
- Prevent
lawn mower and trimmer damage to the bark.
- Remove
plastic nursery tree ties and other string attached to branches
or trunk.
- Never use
wire or rope for any reason, to tie around the trunk or the
branches of the tree.
- Avoid cultivation
around the base of the tree (e.g. planting flowers or bulbs).
- Avoid the
use of white decorative rock which can reflect too much sunlight
onto the trunk.
- If using
decorative rock around the base of the trunk keep it pulled
back yearly so it does not become imbedded into the tree as
the trunk grows in diameter. This applies to the larger size
river rock, boulders, and landscape fabric.
- Once planted,
do not change the grade level around your tree.
- Begin proper
pruning techniques approximately three years after the tree
has been pruned.
Homeowners Should Be Wise
Consumers When Hiring Tree and Lawn Care Companies.
Spring Snow Storms When Trees are Leafing Out
Heavy snow accumulations, while trees are in leaf,
will break off limbs that have decay, are weakly attached, or
poorly formed. When a limb is broken out of a tree, a jagged
stub may remain in the tree. It is usually best to prune
this stub back to another limb or the trunk. Damaged branches
can be an easy entryway for insects and diseases to attack the
tree.
Gently shake or brush off snow accumulations on
the branches of smaller trees. Be careful not to damage the bark
in the process.
Late Spring Frosts /
Freezes
Frost or freezing temperatures in late spring
during or immediately after leaves have emerged often kills the
new leaves. Even though the leaves have shriveled and turned
black, the tree is most likely NOT dead.
There are many dormant or latent buds all over
the tree limbs and trunk. If the leaves are damaged by a
freeze, hailstorm, or other event, a healthy tree will most likely
push out a new set of leaves from these dormant buds. At
leaf-out in the spring, a tree is at its lowest level of stored
energy. Pushing out a new set of leaves can diminish energy
reserves to a critical level in the tree. The tree is now
in a weakened or stressed condition.
A stressed tree is more susceptible to insect
and disease attack. Watch for insect infestations on leaves
or branches, or any branch discoloration which may indicate the
presence of a disease. Determine the insect or disease problem
and treat the tree accordingly.
A stressed tree is also more sensitive to weed
killer applications that may occur on the lawn area above the
tree's root system. Eliminate or reduce the application
of weed killers to lawn areas above the root system of the tree.
The second set of leaves a tree may produce in
one season are usually smaller and fewer in number. A tree
can lose its leaves due to heavy insect infestation, transplant
shock, or drought, to name a few problems. Leaves do not
heal. Whatever happens to a leaf early in the season will
continue to show the damage until leaf-drop in the Fall.
What qualities should I look
for in buying a tree?
When you buy high-quality trees, with proper planting
and maintenance, you will enjoy a healthy tree for years.
When you buy a low-quality tree, the tree will have problems that
will cost you time, money in maintenance, and years of frustration.
The tree should have an adequate root ball in proportion to the
tree size. Make sure the roots are not crushed or broken, black
or dried up, and do not have a circling growth pattern.
The trunk will be free of mechanical damage and unhealed wounds.
Check for improper pruning such as stubs being left on the tree.
Also, excessive pruning on the tree's branches indicates previous
problems that you can inherit.
The branches should be well spaced and not broken. The main leader
of the tree should not be removed unless it is a fruit tree. (The
main leader on fruit trees are often removed to support the fruit's
weight and to make it easier to harvest the fruit). Make sure
the branches are not weak from where multiple stems squeeze together
or squeeze against the trunk. The general appearance should be
clean, not a ragged appearance.
When should I prune
my shrubs?
Prune most shrubs after
they bloom. Some exceptions are holly, roses, and blue mist
spirea. These shrubs bloom on current season's growth and
should be pruned in the spring.
Pruning shrubs every few years will help stimulate new growth
and flowers. Remove one-third of the oldest stems as close
to the ground as possible the first year. The following
year remove another third, with the remaining third the next year.
How often should
I water a newly planted tree?
Newly planted trees in Cheyenne will need supplemental
water to help the tree replace feeder roots that were loss during
transplanting and will initially require more water the first
month. Other factors to consider when determining the amount
of water a tree needs are: wind desiccation, temperature, and
rainfall amount.
Slowly deep water to reach the feeder roots of
your tree. These roots are found in the top twelve inches of the
soil. Newly planted trees - apply ten gallons of water for
every one-inch diameter of tree trunk. A three-inch diameter
tree will require 30 gallons of water each week.
During the establishment period, roots are actively
forming and growing. After one or two months, the tree can
be weaned to a smaller amount of water, i.e. watering every week
and then every 7 to 14 days depending on precipitation.
Proper weaning will encourage deeper root development
and make your tree more "drought tolerant".
Can I rototill
around the base of my tree?
Most trees do not have a tap root,
but instead have a spreading "pancake" root system. The
majority of roots are within 12 inches of the soil surface. Therefore,
if you rototill within the top 12 inches of the soil you can damage
the tree's roots. If you want to control weeds you can use
a broad spectrum herbicide like Roundup at the base of the tree.
Avoid getting the herbicide on the tree or on any root suckers
at the base of the tree.
Cytospora
Canker
Cytospora canker is a fungus disease that affects
many different types of trees and can cause branches or the entire
tree to die. Species affected in Cheyenne include: aspen,
cottonwood, poplar, elm, willow, mountain ash, linden, honeylocust,
ash, oak, apple, stone fruits (e.g., cherry, plum, and peach),
and spruce.
The fungus primarily damages trees that are in
a stressed condition. The canker causes a discoloration on the
outer bark of limbs and on trunks. The discoloration can be yellow,
brown, red-brown, on most deciduous trees, and gray or black on
spruce. Occasionally a liquid will ooze out of the canker area
on aspen trees. Oozing a tree resin or gum-like substance can
occur on peach, plum and cherry trees. The fruiting body of cytospora
causes a pimpled appearance on the outer tree bark within the
canker area. Orange threadlike tendrils can be seen on these pimpled
spots.
The appearance of dead branches on spruce trees
can be the first sign of cytospora infection. Areas infected by
the fungus appear as a sunken area surrounded by swollen callus
tissue forming a gall-like structure. Resin will flow out of the
canker sometimes taking on a bluish-gray appearance.
The best control method is to keep
the tree in a healthy and vigorous condition and by avoiding tree
species more susceptible to cytospora canker. Other tree
health factors are proper planting of the
tree, providing the proper amount of
water, correctly fertilizing as needed, using proper and timely
pruning techniques are critical. The second best control method
is to remove and destroy infected limbs or in severe cases the
entire tree. If possible, prune or remove trees during the dormant
season (while leaves are not on deciduous trees), because the
fungus is not actively spreading and it is less likely to infect
fresh pruning wounds on the tree. The disease is spread to other
limbs and trees during the growing season by wind, precipitation,
insects, birds, and possibly pruning tools. The spores of the
fungus can enter and develop easily in bark wounds on the trees.
The cutting edges of the tools used, chainsaws, handsaws, loppers,
or hand pruners should be sterilized before and after each cut
even during the dormant season. Use a chlorine bleach and water
mixture to sterilize the tools, a 1 part bleach to 9 parts water
ratio. Do not store infected limbs on site. As long as the limb
or trunk is green the fungus can live and continue to develop
in infected limbs that have been removed from the tree. Destroy
infected limbs immediately.
Note the
discoloration of the bark on the aspen trees below and the oozing,
orange colored liquid. These signs can be indicators of Poplar
borer or Cytospora canker.
Bacterial
Wetwood / Slime Flux
In Cheyenne this bacterial disease
commonly affects the wood in elms, cottonwoods, willows, and aspen.
Although the slime oozing out of the tree attracts many kinds
of insects, the insects are not attacking the tree. There are
no cures for the bacterial disease. Drought conditions cause the
disease to be more prevalent. The slime will kill cambium cells,
the growth cells between the bark and the tree, and hinder callus
growth around a pruning wound. The bacterial wetwood slime is
toxic to other vegetation including grass.
Click on this Website to learn
more: Colorado
State University Cooperative Extension
Bacterial wetwood or slime flux
oozing out of an old flush cut pruning wound on an American elm.
Photo: David Ohde
Same tree, same problem, lower
on the trunk. Notice the bare soil where the ooze has moved onto
the soil.
Photo: David Ohde
Damaged
Bark on Tree Trunks
Sunscald
damage on southwest side of chokecherry tree
Photo:
Dave Waterhouse
Older chokecherry trees seem to be very susceptible
to sunscald damage. Chokecherries typically grow in a thicket
with numerous root suckers growing around the trunk bases, shading
the trunks of older stems. Growing as a single tree they seem
to be less able to withstand the direct heating of the trunk during
the dormant months of winter.
The winter sun is low in the southern
sky allowing intense heating on the south and southwest side of
trees. Living cells in the tree bark become less able to withstand
freezing nighttime winter temperatures after being heated during
the day. The cells freeze and burst causing living bark tissue
loss down to the wood in the tree. Many Canada red cherries and
other types of chokecherry exhibit the damaged bark on the southwest
side of the tree trunk in Cheyenne. The last five years of drought
conditions causes trees to be less able to withstand other environmental,
disease, and insect problems.
To protect tree trunks sensitive
to sunscald during the leafless months, shade the trunk in some
way on the south and southwest sides. Paper trunk wrap made for
this purpose provides some protection. Trees which grow in the
shade of other trees in a natural forest setting are shade tolerant.
Maple trees, which are shade tolerant, are very susceptible to
sunscald damage.
Caution dictates shading the trunks
of most young trees from October 31st to May 1st. (Aspen tree
trunks do not need to be shaded.) If a paper trunk wrap
is used, it must be removed each year during the growing season.
Do not fasten the paper wrap on a tree using anything that will
pierce or abrade the trunk.
Three Stories
of Tree Failure from Cut Roots and Improper Planting - In
words and pictures.
A Spruce Tree Succumbs
All roots were cut on the north side of this spruce
tree in the cemetery while digging a gravesite in December 2004.
The tree blew down during strong north winds April 13, 2005.
A
Cottonwood Succumbs
A pit was dug on the west side of this large cottonwood
tree sometime in the past. Soil was filled in and the hole was
forgotten -- until the tree blew over May 17, 2005. The white
arrow points to a wood decay fungus fruiting body also known as
a mushroom or a conk. The conk indicates wood decay occurring
below ground on the root system. Most of the large structure roots
were severed when the hole was dug in the past. Wood decay fungus
sets up shop on the damaged roots and begins decomposing the wood.
To have an entire tree fail from root damage is
uncommon. This was a big tree. The potential for significant damage
and injury was very high. The results in the failure of this tree
could have been worse.
Leaves were just starting to emerge. The tree was
less than six feet from the house. It slowly fell to the east,
as the trunk rested on the side of the house, while limbs punched
through the roof in several spots to further distribute the weight
of the tree on the house. If the winds would have occurred exactly
one week later while the tree had a full canopy of expanded leaves,
the results may have been much worse.
The moral of these two stories is:
DO NOT CUT TREE ROOTS. ESPECIALLY, LARGE
ROOTS NEAR THE TRUNK.
Spruce
Tree Succumbs March 17, 2004 - improperly planted 15 - years ago.
20 - year old spruce falls victim
to high winds.
See story below for the root of the problem
The spruce was planted about 15
years ago. The wire basket was left on the root ball and the orange
twine was left in place around the tree. Part of the wire basket
is visible in the photo above, in the center, just below the twine.
Many
nursery trees commonly known as balled and burlapped (B&B),
are sold to the consumer with soil around a part of the root system.
The soil is held in place with burlap, a wire basket, and twine.
If the burlap, wire, and twine are not removed from the soil ball,
they will interfere with proper root development sometime in the
future. The "sometime in the future" could be a couple
of years to 40 years. During that time the tree grows and the
roots develop. When roots encounter a hard object they will have
their growth diverted or they will begin to grow around the object.
When roots encounter the plastic type twine, which takes hundreds
if not thousands of years to break down, or they encounter the
thick wire of the basket, the roots will begin to grow around
them. Sometimes roots or a tree or shrub trunk can successfully
grow around the twine or wire. The plant area where the wire or
twine is located is frequently a weak area and a source of decay.
Sometimes the root or trunk can't grow around the twine or wire
and will instead be girdled or choked resulting in a halt of the
water or food flow which ends in the death of the plant.
Here is the
dilemma. The best possible future growth of the roots is to remove
all burlap, wire, and twine from around the root ball. The best
initial survival of the tree or shrub is not to allow the soil
to fall away from the roots, which is held in place by the burlap,
wire, and twine. To achieve the goal of not letting the soil fall
away from the roots and to remove everything that holds the soil
with the roots is to gently (as gently as 200 to 500 pounds of
soil and tree can be moved) place the root ball in the planting
hole and put some soil around the base of the root ball to stabilize
the tree. Then remove all wire, twine and burlap from around
the top two thirds of the root ball. Put the remaining
soil around the root ball settling it with water. Do not tamp
the soil around the root ball. The goal here is to get the roots
growing out of the root ball as fast a possible. A
sketch of a good planting method.
The spruce pictured above probably cost
$150 to purchase and plant. If it had a good root system it would
have been worth nearly $2500 today. Now it is worth two
winter days of firewood.
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