Weather: My outdoor thermometer registers an odd pattern. While my general perception is temperatures fall until dawn, and then rise, it shows the temperatures dropping, rising, then dropping again. Since I’m not up all night, I don’t know how often it happens. The fact it occurs when I happen to look may be coincidence.
The digital thermometer is about two feet from the house. There probably is some optimal location, but the constraints on its placement precluded discovering it. Its sensor first had to be in the shade and within range of the indoor receiver. The only way to meet those requirements was putting it near the house on the north side that got shaded first in the afternoon. I finessed the min-max record by offsetting the time so that it reset itself after the sun passed in late morning.
By necessity it’s close to the house. I suspect that as the outside temperatures drop, the thermostat in the interior hall triggers the furnace to fire. It then puts out heat that seeps through doors and windows to warm the near area just slightly. So, the outside thermometer is captive to the dynamics of the interior heating system.
It doesn’t really change the recording of the low temperature, which occurs after dawn. This week it didn’t quite reach its lowest on the solstice, but it came close. The coldest morning was November 26 when it went down to 10. December 21 was 12.
Last useful snow: 12/13. Week’s low: 12 degrees F. Week’s high: 56 degrees F in the shade.
What’s still green: Stems on roses; leaves on cliff roses, juniper, arborvitae, and other evergreens, yuccas, red hot pokers, Dutch iris, grape hyacinths, blue flax, winecup mallow, beards tongues, snapdragons, pink evening primrose, vinca, sweet peas, Queen Anne’s lace, chrysanthemum, June, needle and cheat grasses
What’s gray, gray-green, or blue green: Four-winged saltbush, fernbush, buddleia, pinks, winterfat, snow-in-summer leaves
What’s red: Stems on sandbar willow and bing cherries, new wood on peaches and apples; leaves on alfilerillo
What’s yellow: Stems on weeping willows
Animal sightings: The birds are in hiding
Weekly update: The picture that has haunted me most from Hurricane Michael’s landfall on western Florida was one of relatively young trees all broken at the same height, and fallen at the same angle near Panama City.[1]
They reminded me of the damage from the Cerro Grande fire when trees of the same height ignited one another on a steep hillside.
The primary cause of the destruction was the same: clear cutting that removed all the trees at one time. It was inevitable, the first regrowth would be uniform.
The progression of forest development to different species and different sizes occurs over time measured in generations. And, very often, under different environmental conditions.
At the time Florida was logged, timber companies were harvesting longleaf yellow pine. They discovered, in areas where logging was done before the Civil War, that Pinus palustris did not come back.
Early foresters blamed feral hogs that ate the seedlings, and wildfires caused by lightening. Cecil Frost noted that in the period between the enforcement of fencing laws against free-range swine in 1880 and the introduction of modern fire suppression techniques in 1930, some regeneration occurred. It stopped in 1930.[2]
They’ve since learned the effects of fire were complex. First, longleaf pine was more fire-resistant than the invading species like loblolly pine. Second, the invading species were scrub that prevented wire grass from growing on the forest floor. Aristida stricta and Aristida beyrichiana were essential to spreading the fires [3]
There also were problems caused by the tree itself. It took thirty years to bear its first cones. The seeds in the cones took three-years to mature, and good seed crops occurred about every ten years.[4]
The other factor must have been ground and air moisture. Longleaf thrives in areas that get 43 to 69 inches of rain a year on sandy, infertile soils.[5] Many factors, natural and human, can alter that ecology. For instance, the duff left by the loblolly prevents the longleaf seeds from reaching the ground and discourages the wire grass.
As the stand of broken trunks in Florida demonstrated, it is far easier to destroy than nurture.
Notes on photographs: Taken 4 July 2013 on the road to Jémez Springs just after it started rising from the Los Alamos side.
End notes:
1. The photo of "A forest of broken trees in Panama City, Florida, on October 12, 2018" was taken by Brendan Smialowski for Agence France-Presse and reprinted by Alan Taylor, "More Photos of the Incredible Devastation Left by Hurricane Michael," The Atlantic website, 13 October 2018.
2. Cecil C. Frost. "Four Centuries of Changing Landscape Patterns in the Longleaf Pine Ecosystem." 17-43 in The Longleaf Pine Ecosystem: Ecology, Restoration and Management. Edited by Sharon M. Hermann. (Tallahassee, Florida: Tall Timbers Research Station, 1993). 38.
3. Frost. 22.
4. Jennifer H. Carey. "Pinus palustris." U.S. Department of Agriculture, Forest Service Fire Effects Information System website. 1992.
5. Carey.
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