Why do trees get that tall?: Water movement in plants

Ever wondered why trees get so tall — or why they don’t get much taller? Me, too! People who have met me know I think about transpirational pull more than most folks. This topic has fascinated me without pause since I first heard about it, so I want to do my best to explain it in plain terms for this article.

A few years back, researchers at OSU determined that gravity and other forces would eventually overcome the water column in trees, and that this limit on the upward reach of water would limit growth to 350 – 400 feet; tabs kept on the world’s tallest trees show that so far, they conform to this range. Why is that?

Common and Oregon ash species profiles

Let’s take a break from all the issues and events for a long-absent species profile.

For reasons that you’d have to extract from me over drinks, I’d have to say that the ash is my absolute favorite tree. I feel a very personal connection to them — particularly the common ash, Fraxinus excelsior. (Incidentally, this would have been the species of Yggdrasil, the World Ash of Norse mythology.) The only native ash in the Pacific Northwest is Fraxinus latifolia, the Oregon ash, so I feel obliged to look at that, too. In fact, I’d like to take more of a class approach in this particular “species” profile.

It is pretty easy to identify a true ash, which is to say, any member of the genus Fraxinus. They are unique in having opposite branching and compound leaves, meaning all buds and twigs arise directly opposite from one another, and each leaf is composed of several leaflets.

Current events roundup: Super old-school plants edition

We’re due up for a current events post, and this week’s theme is crazy ancient plants. Specifically, let’s talk about the intense gardening jealousy I feel toward the researcher who germinated a 32,000-year-old plant, and how in the world scientists discovered a 298-million-year-old forest underneath a coal mine in China.

So, the recipient of my botanical stink-eye is researcher Svetlana Yashina, who extracted the placenta (photo below) from the frozen seeds of a long leafed campion plant, Silene stenophylla, and grew them into flowers. While the flowers aren’t particularly dazzling (or envy-inspiring), it’s incredible that this plant sprang from a seed that lay frozen in the tundra of northeastern Siberia for 31,800 years.

Upcoming changes & projects

Faithful readers! I have begun my new job on the Lower Shasta-Trinity National Forest in California. All is well in the world of silviculture, save for one thing: I do not have phone service or reliable Internet. So, I’m moving to a two-week schedule since that will be easier to swing in between evething else.

Look for upcoming posts on sudden oak death, tree physiology and maybe even the chemistry of paper milling, as well as a book review comparing various floras for the Northwest. Hooray! You know you are going to love it!

Pacific dogwood species profile

People often ask me what my favorite tree is. It’s tough to say, but if I had to name a favorite genus, it would be Cornus — the dogwoods. I am not alone in loving these trees; they are grown far and wide as ornamentals. They are cosmopolitan, meaning they are found all over the world in similar climate bands. Oregon has two native species, one shrub and one tree. This profile will focus on the tree, which is Cornus nuttallii, or Pacific dogwood.

This species is small, generally staying under 25 meters in height. It is also a bit of a fragile beauty, as it is very susceptible to dogwood anthracnose; this disease is caused by the fungus Discula destructiva. It has killed many older trees in the wild and makes this particular species less favorable as an ornamental tree.

From a plant’s perspective

I haven’t made a current issues post in a while, and something from 2007 may not qualify as ‘current.’ But the idea that “looking at the world from other species’ points of view [can be] a cure for the disease of human self-importance,” seems as relevant as ever.

This is a TED talk about looking at the world from a plant’s perspective, which close friends know is a subject that is dear to me. The speaker, Michael Pollan, is the author of books like The Omnivore’s Dilemma and The Botany of Desire (which I hope to review at some point). I first saw this link posted by a friend/coworker of my husband‘s. The two of them cook for a fabulous Japanese restaurant here in Portland, so I’d imagine they approach this talk from a foodie angle, while I approach it from — spoiler alert! — a botanical perspective. I want to make some comments after the video:

Oregon white oak profile

Quercus garryana is a special tree because it is the only native oak found north of Eugene, OR. It lives on the west side of the Cascades, primarily in the Willamette, Umpqua and Rogue River Valleys, and along the Gorge. It also occupies a similar range in Washington and British Columbia, and grows up into the foothills in California.

It is a very drought tolerant and slow growing tree. Historically, frequent low-intensity fires have maintained its dominance on oak savannas throughout its range. Because it is fire resistant when mature and a vigorous sprouter at all ages, it is adapted to thrive in this type of fire regime, which also keeps the seedlings of faster growing species at bay. Native Americans set fires in these habitats to promote the growth of important food sources like the Camas lily, prized for its starchy bulbs (and pictured with oaks above).

Douglas-fir species profile

I thought it might be nice to go back and cover some of the basics about forestry for the benefit of readers who want to learn more. Specifically, I think some of you have been waiting for tree ID posts since I started this blog. I know I get excited about knowing what plants are around us.

This might be old news to many of you, but I’m going to start doing species profiles of native woody plants in this area. What better way to start than with one of the most common sights in the Pacific Northwest: the Douglas-fir!

The first thing to know is its many names, because they say a lot about this particular tree. The Latin name (genus and species) is Pseudotsuga menziesii. The species name refers to the person who discovered this tree, and the genus name means “false hemlock.”

Solving the mysteries of the outdoors: A book review

stone wall image via virginia trails at WordPress

This Christmas, my sister gave me a copy of an interesting dichotomous key called Forest Forensics by Tom Wessels. Of course, I read it immediately in service of my ongoing quest to know everything. Then, I typed up this post, saved it as a draft and promptly forgot about it.

So, from the dusty annals of last week, I present: my not-so-long-lost review! And I promise it will be much less intense than my last one. Read on, dear readers, without fear of alienation or boredom!

Welcome, 2012!

Water dragon image via Wikipedia

As we prepare to usher in the new Year of the Water Dragon, I wanted to tell you guys what I have up my sleeve for this blog, and ask for your input, too.

You can expect more book reviews, notes/questions on readings, and periodic updates on what I’m doing with school and our SAF student chapter. In addition, I want to do some current issues roundup type posts that collect relevant news stories and link to great articles I find. I’ve also got plans to interview some of the authors of the books I review for extra insight and possibly a sort of virtual mentoring vibe. Finally, I want to do some photo-heavy species profiles with info about identifying certain plants and what makes them special and/or important.

And as promised, I want to open it up to input from all of you. When you initially subscribed or clicked on the link to this blog, what did you hope to see? What would you like to learn? Leave me a comment and let me know, and I’ll do my best to incorporate any suggestions!

Here’s hoping this year is great for us all.