The Flickr Dendrology Image Generatr

Looking eastward at the Middle Falls.

My unmedicated cataractamania continues to assert itself.

In this profile view of the falls at a time of low stream discharge there all sorts of things to look at. First of all, there's all that congealed mafic extrusive rock—basalt of the late-Mesoproterozoic North Shore Volcanic Group. It came spilling out of fissures and lava fountains of the Midcontinent Rift about 1.1 Ga ago. Its pitted appearance here is due to the fact that its amygdules (mineral inclusions) have mostly weathered or eroded out.

What's more evident in this shot than in the ones preceding is the amount of columnar jointing there is in the basalt situated below the flow surfaces. The columns are by no means as crisply defined as they are, say, at Devils Tower National Monument in Wyoming. But they're discernible. The joints or fractures separating the polygonal shafts formed as lava slowly cooled from top downward.

As far as the plant life featured in this frame goes, let's start with the shrubby sprouts cowering in the rock crevice at lower-left foreground. I'm pretty sure they're Beaked Hazels (Corylus cornuta). I've frequently found this Birch Family species clinging to rocky North Woods streamsides.

On the other hand, the trees that have so thoroughly colonized the ground above the far cliff are that great Cypress Family gymnosperm, Thuja occidentalis. I prefer to call it by its really classy common name, Arbor Vitae (Latin, "Tree of Life"). But in these parts it's usually known as Northern White Cedar, or just White Cedar. A true cedar it isn't, but then vernacular labels are often misleading.

As far as its dietary preferences go, the Arbor Vitae is decidedly calciphilic. For that reason, it loves basalt-derived soils, and even nooks and crannies in the calcium-rich stone itself, as this previous post shows. Another Great Lakes bedrock type the tree loves to perch on is the Silurian dolostone often found cropping out along Wisconsin's Door Peninsula and Upper Michigan's Garden Peninsula. As a carbonate sedimentary variety, dolostone also contains plenty of calcium.

To see the other photos and descriptions of this series, visit
my Integrative Natural History of Minnesota's North Shore album.

Taken from the summit of Rabbit Ears Peak and facing southeastward.

My primary source for this this essay is Geology of Southwestern North Park and Vicinity, Colorado, William J. Hail, Jr., US Geological Survey Bulletin 1257, 1968. If you know of a more modern and up-to-date treatment, please let me know.

Near the end of the field camp course, we were taken on a tour of parts of Colorado we hadn't seen before. It was great to be on the road again, and we drove along in our little caravan of Chevy Suburbans very happy to be doing something besides field mapping on rattlesnake- and tick-infested hillsides.

Every so often we stopped at a pullout and the lead professor, a sedimentologist, diffidently mumbled a few inaudible words while pointing tentatively to a chart or map, which not surprisingly usually had to deal with his own subspecialty. Everything was details; there was no overall picture of how, for example, the Rocky Mountains had formed. I wanted to immerse myself in the historical geology and tectonics, but instead I was told about quartile analysis and the varying grain size of sediments.

To my mind, learning about the rock types and stratigraphy we encountered would have been much more fascinating, too. We did have a petrology professor with us, but he was a recent import currently at the English-as-a-twelfth-language stage. As time went on, I did decipher some of his terminology. For example, when he said prad-joe-krace ferdge-ha-spa I knew he meant plagioclase feldspar.

The only way I could get a larger sense of how this magnificent state fit together was to plot our route on a folding Shell Oil road map picked up at a gas station. But such maps were not known for their wealth of geologic description.

All that said, there were some outstanding times on that trip. One of my most vivid memories was our first stop on the way out of North Park. We spent about half a day climbing about on Rabbit Ears Peak, a mass of Oligocene to Miocene trachybasalt topped with two columns of volcanic breccia that give the mountain its name.

While taking the Instamatic slide above, I was standing with my back to one of those breccia columns, at an altitude of about 10,500 ft / 3,200 m above sea level. And I was gazing at a beautifully composed and peaceful landscape of alpine meadows and stands of Engelmann Spruce (Picea engelmanii) that was considerably different than I'd seen elsewhere in the West. The prominent peak a little right of center is Bear Mountain; part of the more flat-topped Diamond Mountain is visible at left. In the far distance, the Front Range is faintly perceptible.

Diamond and Bear Mountains are both formed of trachyandesite intrusions, once again of Oligocene and Miocene age. And they both stand at the Continental Divide, with all waters on their east flowing to the Gulf of Mexico, repeat Mexico, and streams on their west draining to the Pacific.

All the trachybasalts and trachyandesites and associated tuffs and breccias in this range point to one of the intriguing things I did manage to learn in real time during the tour. The Rabbit Ears are, unlike the loftier ranges that border the other sides of North Park, largely volcanic in origin. But what were volcanoes doing here?

In the 1970s, when plate tectonics was still very young and certainly not taught at my field course, the suggested answers were few and far between. Now, half a century later, the origin of the Colorado Rockies in general and their volcanic zones in particular are still a matter of debate.

One leading model posits that the subducting Farallon Plate, which had been scraping along under western North America at a very shallow angle, may have finally cooled enough by the Oligocene to sink underneath this part of the continent at a steeper angle. This would have liberated water from its slab. That in turn would have lowered the melting point of surrounding rock and triggered an upwelling of magma. And a considerable quantity of that molten material reached the surface and erupted in the Rabbit Ears locale and others as well.

You'll find the other photos and descriptions of this series in my From the Hall of Disjointed Memories album.

Taken along E. Camelback Road, between N. 68th Street and N. Goldwater Boulevard, I'm on the Camelback median strip, facing north and looking at a planting on the grounds of the Fashion Square mall.

If you look at this spot on Google Earth Street View, you'll see that this side of the road hasn't changed much—except that this group of handsome trees is gone. What a shame. In its place is a pathetic assortment of scraggily somethings loosely attributable to the Plant Kingdom.

I remember seeing, in the spring of 1992, these Palo Breas burst into glorious bloom. The bright yellow flowers they produced in great profusion covered their branches. It was a dazzling sight.

Back in the early 1990s their species was generally known not as Parkinsonia praecox but as Cercidium praecox. Its native range extends from Argentina all the way up to northern Mexico, a little shy of the US border. But it certainly has been used extensively in the hotter and drier regions of this country.

Palo Breas, like their close relatives the Palo Verdes, are remarkable trees that are often described as being drought deciduous. In other words, they drop their foliage, composed of tiny pinnate leaflets, in dry spells. However, photosynthesis continues in their green, chloroplast-containing stem tissues.

Fortunately, I was able to photograph these particular trees when they were in full leaf. They were also experiencing a sporadic "false spring" flowering, so I was able to examine their floral structure and discover that on each blossom one of the petals was marked with a red spot. As I wrote in my field notes at the time, "this species is the most attractive of all the xerophytic fabaceous trees used horticulturally in the American Southwest."

The habit they show here, with crowns broader than high, are characteristic of the species.

To see the other photos and descriptions of this series, go to my Urban Street Trees album.

Standing along Route 162 and facing eastward. And we're still on the grounds of the Annivesta Missionary Baptist Church.

The intruding tree branch at right foreground excepted, how many Quercus virginiana specimens festooned with Tillandsia usneoides do you see standing by the fence in front of the church?

Or, to translate from BotaniSpeak, how many Southern Live Oaks draped with Spanish Moss do you see there?

For years after taking this photo I assumed there was just one, with an excellent rounded crown, a most noble example of its species.

But then I checked this site on Google Earth Street View. It turns out that there two trees lined up almost perfectly along this line of sight. The nearer one leans toward the camera; the farther, away from it. And when grouped together, they form a greater whole.

I suspect I realized that when I snapped the photo. It certainly would explain why I took the shot from this distance and angle, and why the offending tree branch couldn't be avoided. Had I stepped in front of it, the whole composite tree wouldn't have fit in the frame. But being a naturalist rather than a purveyor of the prettily perfect, I took the shot anyway.

If you perform the Google Earth check I did, you'll see that these two trees are still here. But they seem to be in pretty bad shape, which I would guess is due to at least one hurricane that has hit the Coastal Plain since I ventured by.

The other photos and descriptions of this series can be found in my Botany of the Carolinas Coastal Plain album.

Still on the southwestern side of the Middle Falls, and still looking north-northeastward.

All the pictures I've posted recently of North Country waterfalls remind me a bit of the Monty Python sketch, "This Uncle Ted in front of the house; this is Uncle Ted at the back of the house; this is Uncle Ted at the side of the house . . ."

Nonetheless, I shall persist in my mission of filling out my series with as many shots and descriptions as possible, one post at a time, to add to my growing photographic museum. That museum may be of no interest to anyone else, but it does warm my heart to see where I've been, what I've discovered, and what I can say about it.

So what's to discover here? Well, there's what I mentioned in the write-up for the Part 25 companion image: the North Shore Volcanic Group basalt over which the Gooseberry River spills. It formed late in the Mesoproterozoic era, about 1.1 Ga ago, when mafic lava poured out of fissures in the Midcontinent Rift.

Now, besides serving as the surface on which the water flows, the basalt is the bedrock on which Pleistocene glacial till rests and the Northern White Cedar Forest ecosystem grows. (White Cedar is another common name for Arbor Vitae, Thuja occidentalis). Here that lighter-green conifer is joined by darker-toned White Spruces (Picea glauca), Balsam Firs (Abies balsamea), or both.

One of my main references for this series is John C. Green's highly recommended Geology on Display: Geology and Scenery of Minnesota's North Shore State Parks. In that guidebook, Green notes that the basalt in front of us here is in fact the top of a lava flow, and one that has a billowed surface.

I realize that water covers much of the flow surface. But see if you can spot some of those billows, which formed as the molten basalt bunched up a bit and then solidified.

To see the other photos and descriptions of this series, visit
my Integrative Natural History of Minnesota's North Shore album.

A close-up of an abundantly coniferous conifer growing along the park's shoreline trail.

During my residency in northern New England (in New Hampshire, far from the seacoast) I discovered that the Red Spruce (Picea rubens) is the dominant species of its genus—at least in upland situations. In bogs, on the other hand, P. mariana, the Black Spruce, holds sway.

It wasn't until I started to wander about the Atlantic littoral of Maine that I saw sizeable populations of White Spruce, P. glauca. I'm quite sure that's what this tree is. As other posts of this series indicate, it's a tough customer that braves the full blast of onshore winds, salt spray, ice, and snow. At Quoddy Head its forest marches right down to the cliff-edge where this photo was taken.

Unfortunately, P. glauca is often best known in these parts as Cat-piss Spruce—a reference to the fact that its needles, when crushed, emit an odor that does smell remarkably like the urine of Felis catus.

No matter. As long as one doesn't abuse its foliage, the White Spruce can be appreciated for both its survival skills and its handsome form.

And, as is obvious here, I really like its small, soft-scaled seed cones, which are so different than a Pine's.

To see my other photos and descriptions in this Quoddy Head series, visit my Strange Sort of Spring album.

Winter Tree ID at Wildwood Park, Saturday, February 22, 2025.

Winter Tree ID at Wildwood Park, Saturday, February 22, 2025.

Winter Tree ID at Wildwood Park, Saturday, February 22, 2025.

Winter Tree ID at Wildwood Park, Saturday, February 22, 2025.

Winter Tree ID at Wildwood Park, Saturday, February 22, 2025.

Winter Tree ID at Wildwood Park, Saturday, February 22, 2025.

Winter Tree ID at Wildwood Park, Saturday, February 22, 2025.

Winter Tree ID at Wildwood Park, Saturday, February 22, 2025.

Winter Tree ID at Wildwood Park, Saturday, February 22, 2025.

Winter Tree ID at Wildwood Park, Saturday, February 22, 2025.

Winter Tree ID at Wildwood Park, Saturday, February 22, 2025.

Winter Tree ID at Wildwood Park, Saturday, February 22, 2025.

Winter Tree ID at Wildwood Park, Saturday, February 22, 2025.

Winter Tree ID at Wildwood Park, Saturday, February 22, 2025.