This is a blog about the native conifers of the Pacific Northwest. It is a companion to the Northwest Conifers site. The blog will focus on timely and interesting details about our conifers, their connections to the rest of the environment, and our connection to them.

Monday, February 13, 2023

Favorite Things

Since I have a bit of a reputation for being a conifer geek, people sometimes ask me what my favorite tree is. Would you ask a mother which is her favorite child? With a similar attitude toward conifers, I can’t name a favorite. However, I do have some favorites among the different parts of trees. Here is my list of my favorite things about our local conifers.

Favorite Bark: Ponderosa Pine

Ponderosa pine bark is the clear winner, both for the striking golden color and the distinctive plates that appear to be covered with pieces of a jigsaw puzzle. The bark is more colorful on older trees, most notably on large trees growing east of the Cascades. Climate may also influence bark color. 

Favorite Needles: Noble Fir 

Firs have a reputation for well-ordered needles. Noble fir needles are the epitome of groomed order. They appear to be combed up and out from the twig. The curve where they attach to the twig is unique. The soft points are friendly and touchable. The color has a classy hint of blue. The red fir of California is similar to the noble fir. Where the two interbreed in southern Oregon, they are called Shasta red fir. 

Favorite Cones: Jeffrey Pine

The cones of the pines are larger than those of our other native conifers. The stiff, woody scales make them heavier and more substantive than those of other conifers. My favorite is the Jeffrey pinecone. Its woody scales and characteristic pinecone shape are similar to the ponderosa pinecone, but Jeffrey pinecones are notably larger than those of the ponderosa. The long prickles on the scales are usually bent back so you can safely pick up the cone. It is fascinating how the scales on pinecones grow in rows arranged in spirals. Jeffrey pine has 13 rows that spiral to the left. You can see 8 rows that spiral to the right. Both of these numbers are Fibonacci numbers. You can see this pattern on ponderosa cones as well. The next time you see a cone under a ponderosa, pick it up and check this out. Nature often develops growth patterns that are mathematically interesting.

Favorite Pollen Cones: Ponderosa Pine

Most pollen cones are hidden on the lower side of twigs. The pollen cones of ponderosa pines are prominently visible at the ends of branches. They are large, colorful and arranged like the petals of a flower. How could anyone not love them? 

Favorite Smell: Incense Cedar

If you have ever smelled the wood of Alaska cedar, you will forever be able to identify it by that smell. But it’s not a pleasant smell. On the other hand, incense cedar has a wonderful smell, as you might guess from its name. A few years ago, I was walking up a trail in Yosemite National Park to Yosemite Falls and encountered a wonderfully sweet smell in the trees. A park ranger told me that the smell was from incense cedar trees. It’s no wonder that people willingly spend large sums of money to buy chests made of incense cedar.

Favorite Shape: Subalpine Fir

Conifers are defined by their seed cones. Think about the general shape of most conifers. It is also a cone. It is an attractive shape, of course, but the spire shaped subalpine fir is extraordinary, reaching like the Eiffel Tower into the sky. It is the ideal design for life at high altitudes where the snowfall is deep in winter. Subalpine fir keeps its limbs short so the weight of the snow doesn’t break them. This practical design is the essence of its beauty.

Favorite Fruit: Pacific Yew

We don’t expect conifers to have a fruit, and technically the little red berry-like arils on yews are cones. But the cones have just one scale that surrounds a single seed. The scale ripens to a plump, bell-shaped aril. These arils have a sweet flavor that birds love, which is how yew seeds are dispersed. However, the seeds inside are quite poisonous to humans. So I don’t love them for the taste but rather for their bright red color, a unique thing to see growing on a conifer.

Favorite Fall Color: Western Larch

Most conifers are evergreen. However, a few species go out in a blaze of golden glory in the fall. The only Oregon native to do so is the western larch. In early November, the needles turn golden. By the end of December, they have all fallen to the ground. In spring, new needles burst out, making another striking display, this time of bright green.


Favorite Non-conifer: Oregon White Oak

I do have a favorite tree among the non-conifers. It is the Oregon white oak. It has been a favorite since my childhood. A large oak stood in front of the house on our farm. The oak is a symbol of strength, and the lobed leaf pattern is an iconic symbol for all trees. Unlike most trees that drop their leaves in the fall, the oak holds onto its leaves through the winter, perhaps another measure of its strength and tenacity. Oak trees were the site of many important historical events. One of these is the Treaty Oak at The Dalles, Oregon. It commemorates the signing of the 1855 treaty between the United States and the Confederated Tribes of Warm Springs. Finally, oak trees seem to be on friendly terms with ponderosa pines. You can often see them growing together, for example, in pine-oak woods at the east end of the Columbia Gorge and at oak-savannah sites in the Willamette Valley.

Thinking about your favorite things can be very therapeutic. It's even better to notice the beauty around you when walking in the woods. You can make your own list of favorite things. You might even write a song about them.

Wednesday, February 1, 2023

Are Trees Intelligent?

Recently, I made a posting here on the dangers of personification in nature writing (here). Now I want to consider the tendency we have to ascribe intelligence to trees and other plants. 

Trees do some amazing things. For example, consider what some conifers do when they are in danger of dying from disease or an infestation of insects or fungi. They will direct all their energy into the production of a huge cone crop. What an amazing strategy! Who would have thought that a tree could develop such a strategy to ensure the survival of its offspring. Survival is the key word here, which curiously explains why these trees react in this way. Genetic variability produced some trees that do this when under stress. Trees that do this have a better chance of survival. What appears to be intelligent behavior is simple natural selection.

I’ve seen several accounts of how slime molds can do amazing things that suggest they can behave in an intelligent manner, (for example here). Suppose you construct a maze and place some slime mold in it. You give it some of its favorite food, oatmeal, and you place more oatmeal at the exit of the maze. As the slime mold grows, it will progress all through the maze. When it reaches the food, any slime mold in dead-end passages will stop growing. This looks like an amazing feat, and many popular descriptions characterize the slime mold as showing intelligence. However, scientists suggested the mechanisms that explain the behavior. Learning the mechanisms of how slime molds do what they do seems like learning how magicians do a trick. “Oh, that’s how you did it.” It takes the mystery out of it. It’s kind of a letdown, but we are no longer inclined to think that the slime mold is making intelligent choices. 

Suppose we construct a similar maze. But instead of slime mold, we will run water into the maze. The water will flow through the maze until it reaches the exit. No oatmeal needed. Like the slime mold, the water will stop flowing up the dead-end passages. However, in this case, we don’t think it is so amazing, because we understand the simple process of the flow of the water. It’s natural. In fact, water does this all the time in any landscape where it rains, for example, western Oregon. These mazes become streams and rivers. 

Tree roots grow much like slime mold. They branch out gathering nutrients. The roots that are successful will grow more than others. The same is true above ground. The branches that receive more light will grow more than others. No surprise here. This is just how we would expect trees to grow. 

It's a mystery when plants do surprising things that seem like intelligent behavior. Whenever scientists find something mysterious, they try to find an explanation for it. Once we understand the explanation, of course the behavior no longer seems mysterious. Once we’re in on the trick, we no longer think it’s magic. However, unlike learning a magic trick, this is not a letdown. Rather, as we gain a deeper understanding of how nature works, we experience even greater wonder. And once we understand the explanation for the phenomenon, it no longer seems surprising. In fact, we would be surprised if, for example, slime mold didn’t behave in the way that it does. When we understand the role of natural selection, it’s natural that trees put on a big cone crop when stressed. We would be surprised if they didn’t.

In many of these cases, what appears to be intelligent behavior is just that: appearance. It has a natural explanation. No intelligence needed. When we do the science to find the explanation, we have a richer understanding of nature.

We might say that what looks like intelligence would be better characterized as logic. But the logic is the logic of science. When we understand the processes and principles that are operating, it is, of course, logical that plants would act according to these principles.

Now you might say that all this assumes that we understand intelligence as a human attribute, something that requires a brain and higher levels of thinking and reasoning. As a matter of fact, the standard definition of intelligence refers to this very thing:

The ability to learn or understand from experience; ability to acquire and retain knowledge; mental ability. - Webster's New World College Dictionary

This may seem to be anthropomorphic, but it is our common understanding of intelligence. However, we recognize that many animals demonstrate a similar intelligence. They have demonstrated their ability to solve problems and learn from their experience of their environment. But why should we limit intelligence to animals? If plants can show what appears to be intelligent behavior, why not call that intelligence? After all, language is not static. As we learn more about plant behavior, we may come to see it as intelligent. 

It is true that we think of intelligence as a human attribute. That is normal since we are human. But I would say that it is a mistake to force this description onto trees and other plants. As when considering personification in nature writing, this kind of anthropomorphism may not be appropriate.

Let’s think about why we consider animals to be intelligent. It is just because when we learn more about animal behavior, we see that they reason, socialize, and perhaps even use language like humans. In other words, when we understand them, we see that they possess the same kind of intelligence as we have. It’s just that their lives are very different from ours and we don’t, for example, understand their language. On the other hand, this is not what we see when we learn more about plants. What we see is processes that do not require intelligence. In amazing ways, plants have evolved to adapt to their environment without the need for intelligence.

We make the same distinction about ourselves. We can describe processes that happen in our bodies that are necessary for survival. The processes of the cardiovascular system, endocrine system, lymphatic system. All these amazing processes are essential for human life. However, we would not say that they show intelligence on our part. We are not even conscious of these processes. Similar biological processes in trees do not indicate intelligence either. 

Finally, does calling plants intelligent add anything to our understanding? Does it suggest any new avenues of research or suggest to us any explanation of their behavior? I submit that it does not. We would do better to simply study the amazing processes that trees use to survive, thrive, and reproduce. 

In fantasy writing, trees act with human intentions and powers of action and thought. It is often delightful, but it is good to remember that it is fantasy. The use of similar anthropomorphisms has become popular in some recent nature writing. Writers seem to think that this gives us an elevated view of nature and fills us with respect and awe. However, learning the details about the life of trees should fill us with wonder and awe. It’s better to simply observe them as they are without imposing the story of our existence upon them.