Get your phenology/taxonomy kicks on Bascom Hill

Now that spring has finally arrived, the plants around campus have begun to sprout their leaves and/or flowers. You might have noticed that spring has come a bit late this year. This has caused the plants to also be late in leafing out. There is a study out there called phenology, which studies the timing of growth patterns in plants. Phenology can be of great interest to historians. For example, let's say that you happen to find a bunch of historicl documents from Roman times. These documents are from a vineyard near Naples. According to the records, the vines sprouted quite early in the year 410 A.D. You could infer that it must have been an early spring in 410. So...good for the vines, but overall a very bad year to be a Roman in Britain.

Phenologists have also noted tundra species sprouting earlier just about every year -- a harbinger of warmer springs.

Enough of the history lesson. I took a tour around Bascom Hill today, as required for my Plant Geography course. I focused on a few interesting plants around the hill:

Tulip tree (Liriodendron tulipifera) - This is a very primitive flowering tree. At one time, it was thought to be the most primitive. This species is from SE USA, while the other species in the genus L. chinense, is found in the far east. These two species are closely related. In fact, the two species can reproduce together, even though they have been separated for 10 million years. There are many closely related species which are only found in SE USA and in China. For a long time scientists couldn't figure out why so many of the species were related, despite the fact that they are so far apart. Eventually researchers discovered that the type of vegetation which grows in SE USA and China (deciduous forest and subtropical forest) was very widespread in the Tertiary (around 20-30 million years ago). After the Tertiary, the global climate started to cool down as we slowly headed for the Pleistocene (the time of ice ages). This global cooling greatly restricted these formerly vast forests to small refugia - in SE USA and China. There was also a refuge in Europe, but the ice ages killed that one off. The closely related vegetation between SE USA and China is called the Arcto-Tertiary flora: meaning that the forests once covered much of northern North America, Europe, and Asia during the Tertiary.


Trillium - Part of the Lily family. This plant is an example of a spring ephemeral which takes advantage of warm spring days before the tree leaves have come out. Trillium usually sprouts, flowers, and produces seeds all before the trees have fully leaved out. This is another example of an Arcto-Tertiary relict.

Magnolia tree - one of the most primitive flowering plants. The Magnolia family reaches back over 100 million years - before advanced dinosaurs were around. Another Arcto-Tertiary relict.

Jack in the Pulpit. I don't know much about this species, other than it's a spring ephemeral. Notice the interesting, modified leaf which the plant uses as part of it's flower.

Gingko tree (Gingko biloba) - This tree has been found in the fossil record during the time of the dinosaurs (Jurassic), and was thought to be long extinct. It was discovered in China. Another Arcto-Tertiary relict, although there are no close relatives found in North America. Gingko biloba is the only species left extant in the genus.

Dawn redwood (Metasequoia glyptostroboides) - This is truly a living fossil. Like Gingko, fossils had been discovered of the dawn redwood long before it was discovered in China in 1941. Another Arcto-Tertiary relict, it is now confined to China. It is related to the Sequoia tree, which itself is restricted to the Pacific Northwest. The dawn redwood is actually deciduous - it drops whole "twigs" of leaves each fall.