Geologists report a recent stint of dome-building activity in Stump St. Helens. Prior to the dome-building, the area inside the crater dropped dramatically.
The photo below shows the mountain prior to the dome-building event.
As can be seen in the photos below, the area inside the crater fell anywhere from 6 inches near the crater's edge to nearly 2 feet in the center. Geologists are stumped by this phenomenon and will be studying it thoroughly.
Locals felt some minor quakes and there was some concern about possible landslides. No major injuries were reported and the azalea-type volcano has since subsided back into dormancy. High-tech, biodegradable walls were temporarily erected to hold back the newly-raised land inside the crater. As the new land inside the crater settles and stabilizes, the walls will be removed (if they have not decomposed).
Samples taken from the new dome show that the composition of the underlying magma has changed dramatically from a pure Swanson's type magma to one of nearly equal parts Swansons magma, clay, and peat. The new dome is hypothesized to result in larger future spring eruptions.
Ok, so here's what REALLY happened. The azalea 'Mt. St. Helens' planted in this burned-out stump hasn't been doing so well in the last few years, and I think it's because the soil (which was some Swanson's mix, I don't remember which) never was the best for an azalea in the first place. Add to that the high pH of wood ash, even though we removed most of it before adding the soil and our *cough* somewhat negligent watering habits in the summer, and it's not the best place for an azalea. Surprisingly it drains well in the winter, so I'm hoping that the addition of some of the native clay soil and peat moss will improve moisture retention and bring the pH down enough to make it happy. Of course we'll still have to remember to water it in summer (and keep the deer off of it.
In the first picture, you can see how it's listed to the side as the soil broke down and settled. Now that it's back in the center of the stump and a bit higher up, I'm hoping the deer won't be able to reach it as easily.
I dug out the azalea and most of the soil and put both on a tarp while I worked (and if I had been thinking instead of huffing and puffing, I might have taken a picture of this). There was about 2 or 3 wheelbarrows-full of soil in the stump. Once I had the soil dug out, I started adding it back to the stump, mixing it with some of the native soil (which is high in clay) and peat moss. I added two full wheelbarrows-worth of native soil and about 3 cubic feet of peat. Boy that clay soil is heavy!
The new soil level is about 6 inches above the lowest point on the rim of the stump, raising it about 10 inches from the previous level, so I used some cardboard as temporary walls to hold the soil in. I'm expecting it to settle quite a bit, though it shouldn't fall as far as before with the addition of the clay soil. After it settles a bit, I'll remove the cardboard and, if needed, I'll add some rocks in the low spots of the stump to hold the soil in.
I really hope this solution works. If not, at least it's bought a few more years to wait and see what the azalea does before I have to do anything with it again! Now I need to make the surrounding bed worthy of this unique centerpiece. It has a loooong way to go.