By Steve Roark
Volunteer, Cumberland Gap National Historical Park

It interests me how trees are so often intertwined with our culture and history. The 250th July 4th celebration of our Independence is a good time to review the history of the Liberty Tree, a symbol for individual liberty and resistance to tyranny.

By Steve Roark
Volunteer, Cumberland Gap National Historical Park.

Confession time: I am not good at math.

I use it, it’s great, we went to the moon with it, yada yada. But I don’t think well mathematically and strive to understand it. But I was amazed to discover that trees use mathematics to arrange their leaves on a twig to optimize their collection of sunlight for the photosynthesis thing. Leonardo da Vinci picked up on this long ago. The “impress your friends” word of the day is phyllotaxis: the arrangement of leaves on a stem in relation to each other.

Trees arrange their leaves in three major ways: whorled, opposite, and alternate. Whorled is where several leaves encircle the stem at one point, which is uncommon. Opposite is where the leaves are arranged in opposing pairs on each side of the twig. Dogwood, all the maples, ash and buckeye use this arrangement. Usually, each successive pair of opposing leaves forms at right angles to the original pair, thus minimizing shading each other from the sun.

The math really starts kicking in with the alternate leaf arrangement, which I used to define as leaves forming on the twig randomly and not in pairs―but they are not random. With alternate arrangement the leaves form in a spiral along the twig, and how many leaves form per complete spiral is predictable by species.

Imagine you have a tree twig in your hand; focus on one leaf and its location; from that leaf start counting leaves along the twig and how many turns around the twig it takes to return to a position matching the original leaf but further along the branch. For example, if you are looking at sycamore, you will count two leaves with one turn around the stem. With cherry, you will count three leaves and two turns around. Oaks and a bunch of other hardwoods have a 2/5 arrangement: 2 turns around the stem in 5 leaves. There are other spiral leaf arrangement ratios as well: 1/3, 3/8, 5/13 and so on.

But there is a common thread in all of them in that they are all Fibonacci numbers, named after a mathematician who figured them out in the 13th century. I know it is getting a little deep but hang with me. Fibonacci numbers include the sequence 1, 2, 3, 5, 8, 13, 21, etc. Note that when you add two numbers in the sequence together, they add up to the next highest number.

So if you look, 1+2=3, 2+3=5, 3+5=8, and so on. Interesting yes, but what is critical about Fibonacci numbers is the ratio between them. If you divide a Fibonacci number by the next highest number, it will be 0.618034 times as large as the number that follows. The Greeks called this ratio the “golden mean” because the proportion 0.618034 to 1 is the mathematical basis for almost all spirals in nature: leaves spiraling up a twig, the arrangement of bracts on a pine cone, sunflower seed arrangement on the flowerhead, even the spiral of a snail shell.

What it boils down to is that in nature, a spiral based on Fibonacci numbers is a very efficient design form, and in the case of trees it minimizes how much each leaf shades another, meaning better sunlight collection and thus more food production. So next time you are in the woods, keep in mind that there is purpose in almost everything you observe. This is both awesome and humbling.

The average American diet includes one of three meats, either beef, pork, or chicken. I always thought we ate more beef than anything, but chicken has of late given beef a run for its money. And if you look at it on a global scale, it turns out that beef is often not “what’s for dinner”.

Play a guessing game with me. Take a minute and jot down what you think are the top 10 land animals butchered for food on the planet, based on the number of animals, not pounds of meat. You got it? So, what’s your number one? If you picked chicken, give yourself a drumstick. A staggering 50 billion chickens are consumed annually. Considering how many ways you can eat chicken in a Chinese restaurant, that’s not surprising. How about your number two? The surprising answer is duck, coming in a 2.6 billion. Pigs come in 3rd at 1.3 billion, so take that, McDonalds! 4th place goes to another surprise: rabbits at 1.1 billion. Next is turkeys at 630 million, sheep are 6th at 520 million, and goats are 7th at 400 million. So where’s the beef? Eighth place at 293 million cows, followed by water buffalo, and finally camels.

By Steve Roark
Volunteer Cumberland Gap National Historical Park

If you've ever picked up an old board or a rock that's been lying on the ground a while, you've no doubt found pillbugs, which live in moist, dark places. They are also known as sowbugs or rollie poley bugs but are called Isopods by the science guys.

When it comes to trees, we live in a blessed place, with more varieties of trees, shrubs, and vines than anywhere in the world except maybe the tropics. Each tree and shrub has its own unique leaf that, with a little practice, will allow you to identify it.

With summer upon us we will instinctively seek shade to get out of the hot sun, which can be readily provided by trees. No one will argue that trees add value to a home, but a well-placed shade tree can save on energy costs as well.

Hickory trees are so common in our area that most of our woodlands are classified as the "Oak-Hickory" forest type. They provide humans and wildlife with important food and fiber.

There are several hickory species growing in our area, the three most common ones being Shagbark, Mockernut, and Pignut. All have compound leaves that have 5 to 9 “leaflets”. The leaves and nut husks have a strong spicy odor. The bark can be identified by its diamond shape pattern and hardness. The easiest hickory to identify in the woods is Shagbark, which has bark that hangs down in long shaggy plates that bend away from the trunk. In earlier times the non-shaggy species were called “tight bark” hickories. They will grow almost anywhere but are more often found on dry slopes and ridges.

As an amateur naturalist I have a curiosity to know how things work. In college I once saw the chemical reactions involved in photosynthesis laid out on a large poster. This all-important method plants use to make food for themselves (and ultimately us) was incredibly complex and took up half the wall. It is so complex that it’s tempting to simply say that plans bring in carbon dioxide and water, add sun energy, then a miracle happens and out comes oxygen and food. This is true but let me attempt to elaborate on the miracle part.

Many sayings or colloquialisms are centuries old but still in common use today. Most of them originated in Europe and have surprising beginnings.

Armed to the teeth: In Scotland the ruler “Bonnie Prince Charlie” was preparing for war and sent out word to his captains to gear up for battle, and rendezvous at a place near the Teeth River. His message was “Come armed to the Teeth”. Another theory is that pirates of Jamaica in the 1600s wanted to maximize their weaponry and would carry a flintlock in each hand and a knife in their teeth, hence the phrase.

Violets are very abundant this time of year and are probably the most common and the easiest to identify family of spring wildflowers in our area. You can find them about anywhere, even in your yard unless you’re a grass purist that uses herbicides.

Wild violets typically have heart shaped leaves that are blunt toothed along the edge. The flowers have five petals arranged so that two point upward and three down, with the lower middle petal sticking out a little longer than the others to provide a landing zone for pollinating insects.