Tree Notes is about trees -- especially native trees, trees for wildlife, and trees in history.

Thursday, August 30, 2007

Cottonwood Trees of My Childhood

Friendly giants in the schoolyard

When I was a child, growing up in the ranch country of northern Nebraska, we lived in a low-lying valley with two creeks and big sandy hills all around us. I attended a little one-room country school, about two miles from my house.

Duff Valley School in southern Rock County, Nebraska, 1965I can't imagine my childhood in that school without the big cottonwoods (Populus deltoides) that grew on the schoolyard. The trees were very much a part of our playground experience. Most importantly, without the cottonwood trees, we'd have had no place to hide when we played "Hide and Seek."

I remember affectionately one very large cottonwood that grew in the ditch just off the school property. In truth, we weren't supposed to venture off the grounds, but the teacher never said anything about us hiding behind that tree. Its trunk was so large that several of us could hide there together -- that's why we liked it so much.

Behind the barn (a relic of the time that children rode horses to school), the big boys had nailed some boards to two cottonwoods that grew close together. If you were brave and naughty (as the big boys were,) you could climb those boards like a ladder, get on the barn roof, and slide down on the other side.

In the fall, we played in the leaves, and in the spring, we enjoyed the beaded strings of "cotton" and the red blossoms. And of course, we all knew how to fold a cottonwood leaf and make a whistle.

I remember how outraged we all were when the school board (our fathers!) cut down one of the big old trees one day. They said it was threatening to fall on the schoolhouse.

Large cottonwood tree in Hopkinsville, KYA large cottonwood that grows near Little River in Hopkinsville, KY
As I've been writing this, I've realized that the cottonwoods grew only around the edges of the playground because the playground was mowed each year before school started.

I don't know if the trees sprang up from seed originally, or if they had been planted. They were mature trees in the 1950s and 1960s when I was a child.

In 2000, when I visited the little, vacant schoolhouse, many of the big trees were dead, standing like whitened skeletons around the playground. Cottonwoods live about a century, and their time was complete.

Sunday, August 26, 2007

Tree care after storm damage

What to do for wind and ice damaged trees

We're having an extreme drought in Kentucky, but our neighbors, Illinois and Ohio (and other states, as well, ) have recently had bad floods and storms.

The storms have been hard on trees. Damage to both publicly and privately owned trees is widespread. For example, CBS reports that 3300 Chicago trees are damaged or down.

I know the sick feeling of seeing your yard full of broken trees after a weather event. (It was back-to-back ice storms in our case.) Don't lose heart! With proper pruning and care, many storm-damaged trees can recover. How to procede?

You might start by following "the three D's of pruning," said Robert Polomski, a consumer horticulture specialist with the Clemson University Cooperative Extension Service at Clemson, S.C.

"Remove dead, dying or diseased limbs at any time of year and especially after any storm event," he said. "If you're not sure about the health status of a limb or even its integrity, you can wait and look for any subsequent growth. When in doubt, contact a certified arborist or other trained professional."

"Plants, Trees Often Tough in Storms" by Dean Fosdick, Associated Press

Unless you're a trained professional yourself, don't get on a ladder to trim your trees, and especially, don't get on a ladder with a chain saw. If you can do some pruning from the ground, review the principles of pruning before you start cutting. Also, be very sure that you know where branches will fall -- and stand clear!

If you're hiring someone to prune the storm-damaged trees, make it very clear to them that you do not want your trees topped or headed back. You just want the broken branches trimmed back to the first undamaged branch.

Be sure the tree-trimmers understand how to make a pruning cut that will not rip the bark down the tree. Make them describe to you exactly what they are going to do, and then supervise them while they are doing it. After all, you are paying them and you want the job done right!

Agree on the fees in advance, and be sure that anyone you hire has insurance!

Sherry Rindels of the Department of Horticulture, University of Iowa, writes that the first priority is dangerous tree damage. If the tree branches are in a power line, call the power company immediately. Look for tree damage that threatens lives or property, and take care of it next. Then you can make decisions about the remaining situation. (Advice from Rindels's bulletin titled "Tree Care Following Storm Damage.")

A University of Arkansas Extension Service bulletin offers some practical suggestions for determining which trees to deal with first. Tree damage that is not urgent includes:

- Trees with broken tops, which still have four or more live limbs remaining.
- Trees leaning less than 45 degrees.
- Windblown trees with roots still in the ground

(Source: "Picking Up After the Storm")

Other helpful information:
Tree Care After Storms
Repairing Storm Damage to Trees
Hiring an Arborist

Free field guide for trees of the Northwest

Free tree guide to download

Washington Trails, a publication of the Washington Trails Association, has a free field guide for Washington trees in its August, 2007, issue. It's also available online as a pdf document.

Wednesday, August 22, 2007

Top Ten Street Trees of New York City

Most common trees along New York City streets

A recent tree census found that the following are the top ten street tree species in New York City. The percentages show the breakdown within the top ten.

1. London plane tree 15.3%
2. Norway maple, 14.1%
3. Callery pear, 10.9%
4. Honey locust, 8.9%
5. Pin oak, 7.5%
6. Little leaf linden, 4.7%
7. Green ash, 3.5%
8. Red maple, 3.5%
9. Silver maple, 3.2%
10. Ginkgo, 2.8%

These statistics are from an interesting article about urban forestry in New York City: "Census Shows Street Trees Add Value To City Life", by Linda J. Wilson, The Queens Gazette, August 22, 2007.

Here's one way to think of the percentages. Of every thousand of NYC's top ten street trees, 153 would be London plane trees, 141 would be Norway maples, 109 would be Callery pears, etc.

Sunday, August 19, 2007

Ohio and yellow buckeye trees

Buckeye trees of Kentucky

My father was not a superstitious man, but he had a degree of interest in folk remedies. When he moved to Missouri where there were buckeye trees, he heard that carrying a buckeye in your pocket would help rheumatism. He put one in his pocket and carried it for years.

The buckeye is a beautiful nut. Deep chestnut in color and naturally glossy, it's a joy to behold and to touch -- a nice bit of cargo for a pocket. The attractive appearance of the nut's exterior is at odds with the contents -- the nut meat is bitter and poisonous. Thus, it has limited wildlife value, and farmers don't like buckeye trees growing in their pastures.

If we see a buckeye tree in western Kentucky where I live, it's probably an Ohio buckeye (Aesculus glabra.) You might find an Ohio buckeye growing as an understory tree in almost any wooded area where the soil is coarse. They're not particular about the drainage of their growing-site. They prefer moist soil, but they'll grow in dry sites that get moisture sometimes. The one thing they really hate is heavy clay soils.

In the highlands and mountains of eastern Kentucky, you'd be more likely to find a yellow buckeye (Aesculus flava, also called Aesculus octandra.) The yellow buckeye can grow quite a bit taller than the Ohio buckeye, with a longer, straighter trunk, but it needs a coarse soil and a cool, moist site to really flourish. Typical height for an Ohio buckeye is 40-50 feet, compared to 70 to 80 feet for the yellow buckeye.

Ohio and yellow buckeye leaves are easy to recognize and remember, once identified. They both have a palmately compound leaf with five leaflets. (Palmate means radiating from the base in a fan-like shape.) You might think of five fingers radiating from a very skinny wrist (the stem.)

Both trees are sometimes planted as ornamentals because of their interesting, rugged shape and the bright orange and red color of their autumn foliage. Both have yellow flowers in late spring or early summer after their leaves are fully developed.

Neither the Ohio buckeye nor the yellow buckeye is particularly susceptible to wind and ice damage. You will need to provide moisture in dry spells and shelter from wind or their leaves will get crispy around the edges. Remember -- they are an understory tree in nature.

The yellow and Ohio buckeyes are the two most common native buckeye trees of Kentucky. Two others are mentioned as rare in Trees & Shrubs of Kentucky (see bibliographic info at bottom of this column): the red-and-yellow buckeye (Aesculus discolor) and the red buckeye (Aesculus pavia L.) I was interested to learn while writing this post that the red buckeye is mentioned by the Tennessee Valley Authority (TVA, source of our electricity) as a shrub to use in shoreline stabilization.

All of the Kentucky buckeyes (and all the other North American buckeyes) are members of the horse-chestnut family.

Friday, August 10, 2007

Helping trees survive the drought

Water your trees during long, dry spells.

Sycamores along Little River, east of Hopkinsville, KYToday I noticed that these sycamores along Little River east of Hopkinsville are losing some leaves. Sycamores drop a few leaves all the time, but these trees had many brown leaves mixed in with the green. They're dropping more leaves than usual, earlier than usual, because of the drought. They're near a small river, but the river is nearly dried up.

I've also noticed dead and dying leaves on other trees. Today, in the wind, a surprising number of fallen leaves were floating around under the trees in our yard. It's dry, dry, dry here.

Our local horticulture specialist from the UK Extension Service, Kelly R. Jackson, wrote recently that sycamores, buckeyes, and yellow poplars (tulip trees) are likely to drop some of their leaves early this year. He also commented:

Some plants are more prone to drought related problems than others. Those showing widespread decline and death during drought periods over the last 10 years in Kentucky include dogwood, burning bush, sugar maple, hemlock, dwarf Alberta spruce, white pine, Japanese maple, birch, Taxus (Yew) and Norway Spruce. Some native plants with a good survival rate and adapted to poor landscape sites (shallow soils, compacted soils and other disturbed soils) include pitch pine, pignut hickory, white oak, southern red oak, bur oak, chestnut oak, dwarf hackberry, fringe tree, Virginia pine, American hazelnut, scarlet oak, shingle oak, black jack oak, post oak and black gum.

Source: "How To Care For Trees Stressed By Drought", by Kelly R. Jackson, Kentucky New Era (subscription required), August 4, 2007.

Jackson says we should be watering our trees if possible, an inch per week or more, given all at once. However, be careful not to overwater. Be aware that trees in well-drained sites will need water sooner than those in flatter, damper sites. Up to 3 inches of mulch under the tree will help conserve moisture and keep down plants that compete for water.

We have a large, elderly sugar maple in our front yard, and I am going to water it this weekend. We have a large yard and we can't water all our trees, but it would be a great loss if that maple died.

Native trees for dry, steep sites

Native trees that will grow on dry hillsides

These native trees will tolerate sites with excessive drainage -- hillsides, banks, or slopes, and extremely coarse soils. They will also tolerate droughty conditions, though most of them would like to have a little water sometimes. The common name of each tree is linked to its page in the USDA Plants Database.

Betula populifolia -- Gray birch (tolerates wet to dry conditions)
Carya tomentosa -- Mockernut hickory (prefers some moisture, tolerates dry)
Cotinus americanus -- American smoketree (prefers moist, tolerates dry)
Crataegus crusgali -- Cockspur hawthorn (prefers moist, tolerates dry)
Crataegus mollis -- Downy hawthorn (prefers moist, tolerates dry)
Crataegus nitida -- Glossy hawthorn (prefers moist, tolerates dry)
Crataegus phaenopyrum -- Washington hawthorn (prefers moist, tolerates dry)
Crataegus punctata -- Frosted (or dotted) hawthorn (prefers moist, tolerates dry)
Fraxinus quadrangulata -- Blue ash (tolerates wet to dry conditions)
Juniperus virginiana -- Eastern redcedar (tolerates wet to dry conditions)
Liridendron tulipifera -- Tuliptree or yellow poplar (prefers some moisture, tolerates dry)
Maclura pomifera -- Osage orange or hedgeapple (prefers moist, tolerates dry)
Pinus banksiana -- Jack pine (prefers some moisture, tolerates dry)
Pinus ponderosa -- Ponderosa pine (average to dry conditions)
Pinus rigida -- Pitch pine (average to dry conditions)
Populus deltoides -- Cottonwood or eastern poplar (tolerates wet to dry)
Prunus americana -- American wild plum (prefers some moisture, tolerates dry)
Prunus pennsylvanica -- Pin cherry (tolerates wet to dry)
Quercus marilandica -- Blackjack oak (dry)
Quercus muhlenbergi -- Chinkapin oak (dry)
Quercus velutina -- Black oak (prefers some moisture, tolerates dry)
Rhus species -- Various sumacs (prefer some moisture, tolerate dry)
Robinia pseudoacacia -- Black locust (prefers some moisture, tolerates dry)
Sassafras albidum -- Sassafras (tolerates wet to dry)

Tuesday, August 7, 2007

Sassafras: The root beer tree

Sasafras albidum

Sassafras leavesSassafras (Sassafras albidum) is one of the easier trees to identify by its leaves. Sassafras leaves can have a mitten shape, with either a left thumb or a right thumb, or the sassafras leaf can be three-lobed, as shown in the photo at right. It can also have an oval, unlobed leaf. Usually, you'll see all three shapes on the same tree.

The sassafras tree is a member of the laurel family so it has aromatic foliage. Rub a leaf between your fingers, and its scent may be obvious. The intensity of the aroma seems to vary from one colony to another. You can also experience the unique aroma of sassafras by crushing a little twig.

Sassafras tea was widely used in the past for its various medicinal effects. Sassafras root and bark was an important export in colonial times. However, natural sassafras tea has been banned from commercial sale in the US since the 1970s, because of concern that safrole, a compound in natural sassafras products, may cause cancer.

In earlier times, homemade root beer was made by fermenting molassess (sometimes mixed with honey) and sassafras root. Commercial root beer used oil of sassafras and safrole for flavoring. Artificial flavoring or safrole-free sassafras extract is now used commercially, and is available for sassafras candy and other sassafras recipes.

Sassafras trees are native to most of the eastern United States. The trees are typically 35 to 50 feet in height at maturity. Individual sassafras trees in the South, may be taller than this average. The spread is usually about 2/3 the height.

A champion sassafras tree is located at Owensboro, KY. It is 76 feet in height. In 1982, its spread was 69 feet and a trunk circumference of 253 inches (over 11 feet) at 4-1/2 feet from the ground. According to the National Register of Big Trees, the Owensboro tree is still the champion sassafras tree for the United States.

Sassafras albidum suckers from its roots, so the tree is often seen in colonies. In our neighbor's pasture, it grows in a colony along the fence row on a hillside, with black locust trees which also sucker from their roots. It's interesting that an article about sassafras trees in the Appalachians mentions them growing with locust trees there, also.

Small sassafras treeInterested in planting a sassafras tree? It will do well in a sunny, well-drained site, but will not tolerate shady, soggy conditions. If you're digging up a sassafras tree in the wild, look for a very young tree and use ball and burlap techniques to transplant it in early spring.

In spring, your sassafras will have small yellow flowers, and in autumn, small, red-stemmed, dark blue berries, which are enjoyed by birds. The autumn colors of its foliage will vary; leaves may turn yellow, red, orange or purple.

There are potential problems with a backyard sassafras tree. Sassafras is vulnerable to damage from wind or ice because its wood is brittle. It will form a colony from its root suckers, unless you keep them mowed off. The suckers may be a problem for nearby neighbors, as well as for you!

Image credits:
Leaves picture: Wikipedia, under the GNU Free Documentation License
Tree growing on rocks picture: National Park Service, by J. M. Reuter
Young sassafras tree: Copyright © 2007 Genevieve Netz. All rights reserved.

Thursday, August 2, 2007

A free tree field guide you can download

Field guide to Tennessee trees is applicable to surrounding states as well

I happened upon a free pocket field guide to Tennessee trees, written by a State of Tennessee forester. It's in pdf format, so you can download and print it. It has helpful information and good photos.

Download: The All Season Pocket Guide To Identifying Common Tennessee Trees

Click any label...

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Enrich your life with the study of trees.

"The power to recognize trees at a glance without examining their leaves or flowers or fruit as they are seen, for example, from the car-window during a railroad journey, can only be acquired by studying them as they grow under all possible conditions over wide areas of territory. Such an attainment may not have much practical value, but once acquired it gives to the possessor a good deal of pleasure which is denied to less fortunate travelers."

Charles Sprague Sargent (1841-1927)

Print references I frequently consult

Benvie, Sam. Encyclopedia of North American Trees. Buffalo, NY: Firefly, 2000.

Brockman, C. Frank. Trees of North America: A Guide to Field Identification. Ed. Herbert S. Zim. New York: Golden, 1986.

Cliburn, Jerry, and Ginny Clomps. A Key to Missouri Trees in Winter: An Identification Guide. Conservation Commission of the State of Missouri, 1980.

Collingwood, G. H., Warren David Brush, and Devereux Butcher. Knowing Your Trees. Washington: American Forestry Association, 1978.

Dirr, Michael. Dirr's Hardy Trees and Shrubs: an Illustrated Encyclopedia. Portland, Or.: Timber, 1997.

Elias, Thomas S. The Complete Trees of North America; Field Guide and Natural History. New York: Book Division, Times Mirror Magazines, 1980.

Grimm, William Carey. The Book of Trees;. Harrisburg, PA: Stackpole, 1962.

Hightshoe, Gary L. Native Trees, Shrubs, and Vines for Urban and Rural America: a Planting Design Manual for Environmental Designers. New York: Van Nostrand Reinhold, 1988.

Little, Elbert L. National Audubon Society Field Guide to North American Trees. New York: Chanticleer, 1996.

Martin, Alexander C., Herbert S. Zim, and Arnold L. Nelson. American Wildlife and Plants. New York: McGraw Hill, 1951.

Mitchell, Alan F., and David More. The Trees of North America. New York, NY: Facts On File Publications, 1987.

Randall, Charles E. Enjoying Our Trees. Washington: American Forestry Association, 1969.

Settergren, Carl D., and R. E. McDermott. Trees of Missouri. Columbia: University Extension, 1995.

Sternberg, Guy, and James W. Wilson. Native Trees for North American Landscapes: from the Atlantic to the Rockies. Portland: Timber, 2004.

Wharton, Mary E., and Roger W. Barbour. Trees and Shrubs of Kentucky. Lexington: University of Kentucky, 1973.

Wyman, Donald. Trees for American Gardens. New York: Macmillan, 1965.

Photos and text copyright © 2006-2010 by Genevieve L. Netz. All rights reserved. Do not republish without written permission. My e-mail address is