In the late 1980s, I established vegetation study plots at 10 sites along the eastern side of Glacier Bay in southeastern Alaska. These sites were more or less evenly spaced between the retreating Muir Glacier and the terminal moraine which the Glacier Bay ice had built at the end of the Little Ice Age. The youngest site had been exposed by retreating ice in 1968 and the oldest site had been exposed around 1770 soon after the ice melted back from the 1740 moraine. So on average the age difference between “consecutive” sites was about 20 years (202 years ÷ 10).
There are three approaches to learning things from this series of different aged study sites:
You can assume the sites form a chronosequence so that changes inferred from the series of progressively older sites are also changes that have happened at individual sites. According to this assumption my older study sites would have passed successively through stages similar to all of the younger sites.
You can be less trusting of the chronosequence and use evidence at each site to reconstruct its developmental history. This history can be compared to younger sites and to their histories to test the above assumption. Tree rings and paleoecology are potential sources of information about vegetation history at individual sites.
You can wait until each site attains the age of the next older site at the time of establishment. At that time Site 1 should look just like Site 2 did when you started, and so on. If the chronosequence assumption is valid, each site will have aged predictably and you will have a new, slightly older, and now verified chronosequence. You can have some confidence that inferences about change made from that chronosequence are valid.
I saw Riggs Glacier on my first trip to Glacier Bay in 1984. Of the three tidewater glaciers in Muir Inlet at that time, only McBride Glacier reaches sea level today. In 1990, as one of the final field tasks for my dissertation, I established permanent study plots between Riggs Glacier and Muir Glacier. This summer Galen and I used old sketch maps to find all five of them and recorded GPS coordinates.
My second youngest study site at Glacier Bay is on a bench of outwash about 150 feet above Muir Inlet. Before alders covered the young surface in the mid 20th century, the bench offered a good view of the retreating face of Muir Glacier to the north. William O. Field established a photo station there maybe in the late 1940s and marked the spot with a cairn assembled of several large rocks. I found the cairn in 1988 when I set up my study plots in a dense thicket of alders.
It was not easy to find a photo of these bookshelves as they were installed in my parents’ house. The shelves were behind a table and hard to photograph, and they were also not very photogenic. I thought they were cool and modern in the sixties, but I never thought they were important (I do now). The shelves are probably in the background of some other photos, but this one from 1972 was the first I came across and is certainly more interesting than the rest. Many of the books in this shot are still on these shelves.
The levee of Bayou Petit Caillou supports the long strip of houses that is Chauvin and Cocodrie, the narrowest towns I have ever seen. Way down delta in Louisiana, you are either on the levee, in the bayou, or somewhere out in the salt marsh. For exactly 100 years, Cecil Lapeyrouse’s Grocery has been on the levee. Today most of the houses are seasonal, and the store gets by with business from people coming down to shrimp or fish or have fun. We stopped by on our exit from the LUMCON Marine Center in Cocodrie where Public Lab held its annual meeting. That had fallen into the fun category. Continue reading “Gas Ice Bait Beer”
Click photos to enlargeI was really pleased to learn that the archive of my own black and white negatives includes a 1973 photo of Red Dog Lodge. But last week I found a 1967 photo for sale on eBay, and it’s much better than mine. It was taken for an article that ran in the Baltimore Sunday Sun Recreation section (page 11) on December 10, 1967. I inferred that from notes and stamps on the back of the photo, and from a citation of a Paul Wilkes article “Campaign to Save Soldiers Delight” from that date. Continue reading “Red Dog Redux”
The Maryland Historical Society installed the Soldiers Delight historical marker in 1968. It looks brand new in the 1969 photo from The Baltimore Sun archives, and it appears to be on the west side of Deer Park Road near the overlook. I photographed the marker in 1973 when it appears to be on the opposite side of the road. It also appears to have been repaired after being broken off the post. I found a recent photo from August 2009 showing a completely new sign now back on the west side of the road next to the overlook parking. The wording of the sign has not changed, only the number of paragraphs and the number of spelling errors. Continue reading “Marker historical”
Click photos to enlarge.
There are portraits of more than a dozen species of plant among my old negatives of Soldiers Delight. Most of these are characteristic plants of the barrens, like post oak, blue stem, and moss phlox. A few photos are of plants that are uncommon in Maryland except on serpentine. I don’t know these plants well enough to be sure of the identification, and some might be impossible to indentify just from photos. I photographed these between 1973 and 1975 before I paid very close attention to plant names, but I must have been aware that certain species were special at Soldiers Delight. Continue reading “Seldom scene”
Click to enlarge photos Land purchased by the State of Maryland for the Soldiers Delight Natural Environment Area included two historic buildings: Red Dog Lodge and a log cabin said to have been built in 1848. The lore is that the cabin was used as an assay office for the Tyson chromite mining operation. It was apparently well maintained for most of its decades and was well preserved when I photographed it in the fall of 1974 before much restoration had been done. There were no windows or doors, but it had a real foundation (maybe even a cellar), intact chinking, and a mostly functioning roof. Soldiers Delight’s first ranger, E. Vernon Tracy, organized some restoration, and by the spring of 1975 the windows and doors were boarded up and it had a new roof, or at least a different roof. In 1974 there was a patched composition shingle roof, and in 1975 there appeared to be a wood shake roof, but not necessarily a brand new one. So I’m not sure what changed. Continue reading “Assay office”
Below is a diagram that was never shown to me in science class. Alfred Wegener proposed his theory of continental drift in 1912, but it was not until 1960 that most scientists began to accept the new paradigm that continents move around. The idea of crust formation at mid ocean ridges came even later in 1966. So when scientists and teachers in the 1950s and 1960s presented a story about the serpentine rock underlying Soldiers Delight, they got it wrong. Serpentinite is formed in the lower oceanic crust, typically at the mid ocean spreading centers. That’s where it picks up its heavy minerals, like chromium, nickel, and magnesium, which are more abundant in the mantle and deep crust. When Africa floated over here 300 million years ago, a little bit of this oceanic rock got pushed along with it and ended up in the Appalachian Mountains, and in Soldiers Delight. Nobody knew that in 1960.
Red Dog Lodge was built in 1912 as a hunting lodge and has been a symbol of Soldiers Delight for me since I started meeting, playing, and hiking there when I was a kid in the 1950s. It always seemed like a place with secrets, a place where men once did things that weren’t done anymore, things that Tom Sawyer would know about because he had seen them in a book. It was built for Mr. Dolfield, who gave his name to the road I grew up on, and also for the namesake of Sherwood Hill Road where our three-letter friends the Lees and the Coes lived. I knew Mr. Hibline who used the lodge after World War II, but I never knew that he was a person who used it, or what it was used for. It never occurred to me that somebody owned it. So I didn’t know much at all, but it was always good to be at Red Dog Lodge. Continue reading “Red Dog Lodge”