Hi Marianne.
Sounds like a bit of a challenge. One thing that popped out at me was the fire hazard you mentioned, and the on-contour hugel terraces, and the slope, and the rain. Oh, and the instability of the terrain.
These are all components to either a worse fire event or a landslide.
In the normal
course of events, you don't really want to use hugelbeet construction to make terraces, although I like the idea, and I think I know of a way to make it safe. The usual concern is that it will all become sodden as it saturates during rain events, and that it will go visit whoever is living downhill. I think that if the hugel terraces were anchored with rooted stumps and then had strongly-rooting trees planted on the downslope edge, it might still be a good idea to mechanically stabilise the slope with stakes pounded in to keep the hugel components in place, but it would mitigate some of the danger.
Another concern is that anything that acts as a sediment trap placed on-contour will do equally well to trap embers in the event of a fire, increasing the likelihood that everything burns. If your hugel terraces are topped with soil and garden beds, and if mostly everything atop the terrace is either growing or kept damp, eventually the hugel moisture battery effect will keep it in some sort of humid equilibrium, and will act to quench embers it traps.
It looks like you have a beautiful bit of
land, though, and you know what questions to ask. I look forward to hearing more.
Thanks for the pictures. Keep 'em coming, keep us posted, and good luck.
-CK
A human being should be able to change a diaper, plan an invasion, butcher a hog, conn a ship, design a building, write a sonnet, balance accounts, build a wall, set a bone, comfort the dying, take orders, give orders, cooperate, act alone, solve equations, analyze a new problem, pitch manure, program a computer, cook a tasty meal, fight efficiently, die gallantly. Specialization is for insects.
-Robert A. Heinlein