Vine maple roots and potential damage

I moved into a house built in 2001 on a cement slab (slab
height = 18″). Around 1 foot from my foundation is planted a Maple tree.
I have been told that it is a Vine Maple. It is around 15 feet tall. My
neighbor told me to pull out the tree because the roots will crack the
foundation of my house. I don’t want to get rid of the tree unless this
is true. I went to a nursery today, and they said that it is very
unlikely that the tree will damage the foundation (unless the foundation
is already cracked and the roots make these cracks worse). What do you
think? I have no idea if the foundation has cracks that the tree could
exacerbate or if a Vine Maple in general would crack a foundation like
this.

I do think that planting anything one foot or less from the house is not
ideal, especially a tree. However, vine maple roots have a low potential
to cause damage, according to the database of the Urban Forest Ecosystems
Institute (see full tree record for Acer circinatum).

On the question of how close to a house a tree can be planted, I found
the following from New Mexico State University Extension site, in answer
to a question like yours about root damage potential:

“A more important consideration is keeping the branches from rubbing
against the house and damaging the stucco, siding, or paint and shingles.
By planting the plant a distance greater than the expected mature crown
radius from the house, you will avoid damage to the house by branches.
You will still benefit from shade if the tree is properly positioned.

“Many trees are planted so that their branches are trimmed to be higher
than the roof and then grow over the roof. Remember, if one of these
large branches breaks in a wind storm, it can damage the roof, so
distance from the house is the best protection from such damage. Learn
how widely the branches spread from the trunk when the tree is mature and
plant at least that distance from the house. Yes, you can break this
rule-of-thumb, but the hazards increase when you do.”

You may want to consult a certified arborist to evaluate the situation,
and see if you can keep the tree where it is. To find a certified
arborist, contact Plant Amnesty or the Pacific Northwest Chapter of the International Society of Arboriculture.

Acer circinatum, Tree roots

Vine maple fall foliage

I have a vine maple tree whose leaves turn a very plain, rather ugly brown in the fall. It gets full sun from about noon until sunset. From what I have read, its leaves should turn red, orange, and yellow. What can I do to trigger this? I am thinking of how Hydrangeas are different colors depending on the acidity of the soil. I would like a tree with attractive fall color. I have also read it likes moist places in the shade, and it has not had that environment in my yard. Could the amount of water it gets in the summer, or lack of water, be affecting this?

According to J. Harris in The Gardeners Guide to Growing Maples (2000, p. 119),
“Autumn color is due to a chemical change in the leaves and a combination of the
remains of the chlorophyll grains and a substance called anthocyanin. The
color assumed by leaves depends on soil and air conditions and on the amount
of moisture. If conditions are very dry in the autumn, then the color will
not last for long. After a frost, colors appear more intense, but the frost
can check activity. It will also not be so good in very wet conditions.”

The National Arboretum provides a complete explanation of why autumn
leaves turn color.

There is an excellent article from the Seattle Times (September 25, 2008) in which former Washington Park Arboretum Collections Manager Randall Hitchin describes this process. Fall leaves change color during “the final stage in the life of a leaf. [This] has to do with four groups of pigments. You know about chlorophyll, the green chemical that does all the heavy lifting spring through summer. Then there are the carotenoids — carotene and a suite of related compounds — that give leaves yellow and orange coloring. Tannins produce the russets and browns. Finally, anthocyanin provides the classic autumn colors of red and purple. During the growing season, chlorophyll dominates. It’s constantly being made to replace what’s degraded by ultraviolet light, and the leaf appears green. Depending on tree species, yellow, orange or brown pigments have been there all along, concealed by green chlorophyll. In autumn, as chlorophyll production slows and ultimately stops, the yellows, oranges or browns emerge. Anthocyanin is genetically controlled, so some tree species get red and some can’t. Unlike the carotenoids, anthocyanin isn’t usually present during the growing season, but is produced in leaves with fall weather conditions. In trees that can go red, the amount of it depends on environmental factors. In ideal conditions, you see vivid pinks, reds and purples — that ooh-and-ah factor. […] The Northwest autumn is often overcast or rainy with only minimal cooling at night; not optimal for fall color. Another reason has to do with numbers. In the Northwest, the effect of color is diluted because of species composition in our forest canopy, which is typically dominated by evergreens. With the evergreens outnumbering the changing deciduous trees, you don’t get those huge sweeps of colors you see back east.”

There are other possibilities why your vine maple is not producing good fall
color:

1. It might be getting too much light. The natural habitat for the vine maple is
under an overstory of large conifers (Japanese Maples, by J. Vertrees,
2001, p. 247). Afternoon sun is the most intense and could be stressing the
tree. Harris (2000) notes that while tree-like species prefer open sites, woodland conditions and dappled shade are ideal environments for shrubby maples. (Harris., p.
118).

2. Other than light, the environment might be a little off. Vertrees (2000, p. 247) notes that with vine maples, intense color does not develop in environments where abundant moisture and fertility keep the trees from being under stress, i.e., they need stress to produce good color.

3. Trees of the same species will exhibit different fall colors depending
on the growing environment and peculiarities of each individual tree. (As
identical twins can be quite different). When selecting a tree for fall
color, it is best to first view it in autumn — then remember it will change
somewhat when it is installed in a new home.

It is not likely that changing soil pH will have an effect. I have been
disappointed in fall color a couple of times and finally replaced the
trees — after viewing them in full color in the nurseries.

Acer circinatum, Fall foliage

planting to stabilize a steep slope

Can I plant groundcovers, shrubs, and trees to stabilize a steep slope?

There are several resources which will help you in
selecting plants to prevent erosion and mudslides on
your slope.

Please note that these articles are merely suggestions and should not be construed as advice. We are librarians, not engineers!

None of our standard books on trees mentions the soil binding quality of tree roots. However, the Miller Library does have very good technical books and articles on slope stabilization. (For example, Slope Stabilization and Erosion Control: A Bioengineering Approach, edited by R.P.C. Morgan and R.J. Rickson, 1995.)

I do want to note one thing that many articles mention: no amount of established vegetation will hold a steep slope if other forces are present that would contribute to a landslide.

The Department of Ecology website has a list of appropriate plants.

Additionally, there are a number of books with
information on the subject. Vegetative Contribution
to Slope Stability at Magnolia Park (by Kathy Parker, 1996)
recommends Oregon grape (Mahonia), which she suggests
for gentle slopes.

Other smaller plants she lists are:
Polystichum munitum (native sword fern)
Vaccinium ovatum (evergreen huckleberry)
Symphoricarpos albus (snowberry)

Larger shrubs in her list:
Alnus rubra (red alder)
Philadelphus lewisii (mock orange)
Sambucus racemosa (red elderberry)

Small trees:
Acer circinatum (vine maple)
Amelanchier alnifolia (serviceberry)
Corylus cornuta (hazelnut)

For steeper slopes, Parker says that they may not be
good candidates for vegetative rehabilitation unless
you put in some kind of structure. She says that Jute mats can be used in conjunction with native seed, mulch, and shrubs, if carefully anchored. She also mentions a Weyerhaeuser product called Soil
Guard.

Steep Slope Stabilization Using Woody Vegetation (by
Leslie Hennelly, 1994) has a plant list, as well as a chart which indicates plants used to control erosion, the degree
of the slopes, and the rate of success in resisting
erosion.

Two titles which focus more on the garden design
aspect of planting on a slope are
Hillside Gardening : Evaluating the Site, Designing
Views, Planting Slopes (by William Lake Douglas, 1987) and
Hillside Landscaping (by Susan Lang and the editors
of Sunset Books, 2002).

early leaf coloration in vine maples

We planted a clump of vine maple last fall and because we were in a hurry (landscaping a new home), we just put in without amending the soil. It is dealing with extremely sandy soil, though we did give it fertile mulch, and gets full sun all day long. It looks okay, but the leaves have been very red all summer, basically what I would expect it to look like in the fall. We’ve been watering a lot to make up for the sand. What’s the story on vine maples? We had a lot of them at our old house, but they were mostly under fir canopies or at least were not in full sun. Any tips on helping this one out?

I wonder if the leaves on your Acer circinatum are evenly red, and if they look scorched at all. Leaf scorch is a problem for maples in conditions of stress.
See this information from the HortSense database of Washington State University. Excerpt:

“Leaf scorch on maple has many possible causes. Plants that are under
stress, such as drought or heat stress, may not provide sufficient water
to the leaf margins, causing the edges of the leaves to turn brown and
dry. In some cases, scorch may spread to areas between veins or entire
twigs may die back. Trees placed near heat-reflecting surfaces, such as
buildings or pavement, often suffer from heat stress. Excessive salts
from overuse of chemical fertilizers may cause leaf scorch. Scorch may
also be a symptom of damage to the roots or stem.”

If the leaves are not scorched in appearance, it is possible their early
coloring is the result of some other type of stress, or perhaps the leaf coloration has to do with their being in full sun, in an exposed site. You may find this information from University of British Columbia Botanical Gardens (no longer available online) interesting: “The formation of red pigments in the autumn provides protection, preventing the too-rapid breakdown of chlorophyll which could occur in exposed (read: excess light) areas. As you can clearly see in the leaf in the upper right, the bottom-right corner has the pattern of the leaf above. Where the leaf above shaded this leaf, no red pigments were produced. Where the leaf was exposed, bright red anthocyanins were formed. To take this to a broader perspective, vine maple trees in shaded forests and under low light conditions have little need to produce red pigments, as the breakdown of chlorophyll can occur at a modest pace. However, vine maples in exposed sites turn flame orange and red, so that the pigments produced will slow the rate of chlorophyll breakdown.”

An article (no longer available online) from Minnesota Department of Natural Resources discusses premature fall color in maples. Excerpt:

“Each August brings a few trees that begin the fall color frenzy ahead of
schedule. In addition to signaling the change of seasons, these trees are
sending a clear signal that they are suffering from some form of stress.
Stress can have a wide variety of causes, be mild or severe, or, benign
or fatal. In any case, professional tree ‘care givers’ should be aware
that the trees are talking to you. Are you listening?
“Maples are probably the group of trees that most commonly exhibit
premature fall color. Sensitive to changes in their environment, maples
commonly show early color in years when summer rains are heavier than
normal and raise soil moisture to or above field capacity during the
period from mid to late summer. The maples that show this characteristic
the best are the several species of soft maples (silver and red) that
commonly inhabit the shrubby areas around wetlands. These trees commonly
begin to show deep, rich purples as early as the first week in August.
Maples in communities also commonly display early color due to stress
mechanisms more common to the urban environment. Sugar maple, in
particular, shows early color due to the stress induced by infection from
Verticillium wilt. This disease may occur in nursery grown stock in
commercial trade. It is difficult to detect because it is soil-borne,
difficult to culture, and commonly not tested-for in the nursery. In
addition, Verticillium wilt is a relatively weak pathogen that does not
do well on young, vigorous nursery stock. Trees can be infected for many
years without showing external symptoms of the disease. When they do
begin to show symptoms, one of the first is premature fall color followed
in succeeding years by a progressive, if not slow, crown decline and
dieback.”

Maples in communities that are planted ‘just-a-little’ too deep often
show premature fall color. Again this is more pronounced in years with
wet summers. The likely mode-of-action is decreased soil oxygen content.
Planting too deep ‘smothers’ roots reducing oxygen in the root zone. So
does over watering whether natural or artificial. The bottom line is
stress-induced premature fall color. Remember that stress is (1) caused
by many factors, (2) cumulative, and (3) potentially fatal if left
untreated.