There’s been awfully little botany on this blog so far, considering how important plants are to dinosaurs (as fodder, admittedly). Time to have some, then, preferably in a geology context.
Here are a few pictures I took in the vicinity of Mt. St. Helens in 2000, during a pretty cool but partly gruesome field trip.
These are scans of conventional, dead-tree photographs (pun intended), so please excuse the quality.
This shot illustrates nicely how plant communities come back after a catastrophy: the old trees were felled by the volcano’s blast, but some sapling survived. The rest of the suddenly free and sunny ground gets covered by huckleberries first, which makes for very nice fall colors.
Here a more damaged area, where no undergrowth managed to survive. Thus, very few young trees now. More of the topsoil was removed, too, so that perennials have less of a chance to grow. Grasses and annuals have a field day (or, rather, decade).
Here you can see how much relief had of an influence, by shielding some areas (now green), and some not (now not green). Even if all trees were stripped off the slope facing us, the re-growth was a lot faster than in more exposed areas, simply because soil and some undergrowth remained.
There’s been a plethora of studies on Mt. St. Helens, but I am too lazy to look for links now.