T-R PHOTO BY GARRY BRANDENBURG It is hard not to notice an impressive sunset of warm light on the bottoms of these clouds. Light is a fleeting quality that in a few moments will vanish. However, this deciduous tree, in silhouette, helps to frame the image and in its own way, tells another story. Trees stand as silent sentinels, quietly going about their business of living, adapting and adjusting to the seasons. In the springtime, buds pop open and new leaves emerge. By summer time, trees are in full photosynthesis mode to make food for the tree. Cells within the outer layers of a tree pump gallons of water daily into all of its tissues. Come fall, the leaves “paint” a picture of many vivid colors on fading leaves. Their job done for another year, leaves fall to the ground and the tree rests during cold temperatures of late fall and winter. It is a cycle of life that Mother Nature has been conducting ever since the early earth’s atmosphere became hospitable for vegetation growth.

TREES are valuable in many ways. They cover large portions of earth’s surface and by their very existence, create life, sustain life, hold and filter water and air and provide products for people to use. Trees grow and die just like any other living thing. But their seeds, fruits and even roots allow these amazing plants to live for centuries.

We humans may take trees for granted as plants that seem to always be there. With care and a bit of management, we plant trees where we want them for shade and decorative landscape purposes. Mother Nature has a much bigger view of trees than us mortal humans. She thinks very long term to put as many species of diverse trees on earth’s continents that soil, water and sunlight will allow. It is amazing to think about.

So today, a bit of tree history is offered for you. Enjoy. Did you know that in North America at least 568 species of trees exist? There are more if one includes specialty habitats of Mexico and tropical species found along the southern fringes of the United States. But for now, it is easier to concentrate on 232 trees of importance or general interest while lesser time may be spent on 336 species that we tend to overlook. All are important cogs in the wheel of life. So intelligent tinkering means that all these woody plants have an ecological purpose even if we do not understand those roles.

In North America, six broad ecological zones or forest type regions have been identified. Each is different due to moisture, temperature, soils, elevation and latitude. They are named tropical, southern forest, central hardwood, northern, Rocky Mountain and Pacific Coast. For local areas within Iowa, a wide variety of conditions allow lots of generally known trees to grow and also offer unique settings for a much smaller association of tree types. It is a good mix to learn about if one will take the time to study the nuances of Iowa that allow trees of many species to grow.

Tress are survivors, having adapted to earth’s naturally changing climates over geologic time. The trees we may be familiar with today did not always grow here. When glaciers covered the Midwest and all of our northern states and all of Canada, trees could only exist far to the south of glacial ice leading edges. But as climates warmed in long cycles of time, vegetation of all kinds filled any voids on primitive soils left behind by retreated ice. Tundra plants gave way eventually to woody plants of boreal forests. Hardwood species of trees existed further south of the spruces and pines of northern latitudes. Grasses grew where temperatures were warmer and drier. This intermixing of plant types followed retreating glacial ice northward. And many times the cycle of advancing ice would force a shifting of plant zones to go south.

Trees record short and long term weather events. Long periods of warm rainy weather did influence which trees were better adapted to those conditions. If warm weather remained followed by cycles of less rain or even drought, trees either adapted or died in these locations. Earth’s past has had mega-droughts or lots of rain or cold weather with either too much or too little precipitation. Think of any scenario of long term climatic conditions and we know vegetation of all types, including trees, had to make it or perish.

In the book by German forester Peter Wohlleben titled “The Hidden Life of Trees,” he tells of the many ways trees have adapted. Wohlleben said this “Are trees social beings?”

He makes the case that, yes, the forest is a social network. He draws on groundbreaking scientific discoveries to describe how trees are like human families: tree parents live together with their children, communicate with them as they grow, share nutrients with those that are sick or struggling and even warn each other of impending dangers. Anthropomorphic associations aside, trees do all the above on a very slow yet methodical way.

He notes that trees have extremely variable genetics. They have great tolerances for climatic variations, an example being white oak. Forests tend to regulate their own climate. Tree seed dispersal is also varied as in the simple pull of gravity that moves an acorn to the ground. Mice will move acorns a few feet, squirrels a few hundred yards and blue jays or wood ducks a few miles. A white oak that lives to be age 15 years will start producing seeds of its own and continue that task for a few more centuries. Its acorns will be dispersed far and wide. And these seeds being moved by critters of the forest will easily out race a glacier. That is just one example of adapting, by a tree species, to long range influences of natural changing climates.

A tree species named Honey Locust is well noted for its bean pods and the seeds within those pods that nourish lots of wildlife. However, if ice age mammoths kept the pressure on these trees to find the nutritious seeds, this tree over time developed a defense, namely lot of thorns on its trunk, limbs and twigs. Those thorns were a true determent to any large animal because thorns piercing an animal’s tongue, lips, gums or feet could inflict great pain and become a source of infection. The animals learned to avoid the tree. The tree as a species thrived.

FOREST PRODUCTS make lots of things possible. Homes are largely framed by lumber cut from logs at a sawmill. With careful use of trees grown and used for human needs, the supply of wood products becomes a long list. Ash is used for tool handles, tennis rackets and baseball bats to name just a few. But who knew or how many of us now know that the leaves of white ash rubbed on mosquito bites is supposed to relieve the itching?

Basswood uses include veneer, baskets, trunks, coffins, venetian blind slats and is also a fine source of woodland rope, string and thongs for sewing birch bark. For each of the following species of common trees, many uses exist. I’ll not list them, but hopefully make you interested enough to seek out how each wood type can be made into or used for things of good purpose. Here is the wood list: Birch, Boxelder, Butternut, Cherry, Coffeetree, Cottonwood, Elm, Hackberry, Honey Locust, Hophornbeam, Hornbeam, Black Locust, Maple, Mulberry, all the Oaks such as Black, Pin, Red, Shingle Bur, Chinkapin, Post and White, Osage-Orange, Persimmon, Pine, Popular, Red Cedar, Sycamore, Walnut, Willow and Yellow-Poplar.

It is my hope that your awareness of the many types of products made from Iowa grown trees will add to your understanding of the value of each species of tree. Intelligent tinkering requires a knowledge of how all the cogs work together within the ecosystem.

CHRISTMAS TREES are available for purchase at the Izaak Walton League each Saturday and Sunday from now until the Dec. 22. Each tree is a cut your own type of arrangement. Cost is $40 per tree any size. Hours for Ikes tree sales are 10 a.m. until 4 p.m. Enjoy a real tree. Then next spring a new tree is planted in its place to replace what was taken out. Only 17 days remain until Christmas Day.

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Garry Brandenburg is a graduate of Iowa State University with BS degree in Fish & Wildlife Biology. He is the retired director of the Marshall County Conservation Board. Contact him at PO Box 96, Albion, IA 50005.