No photos but it is primarily palm, azalea,oak, and other trimmings from my yard. Some weeds and vines also, which was my main concern since I don't want to propogate weeds and annoying thorny vines by including them in my hugleculture pile. Does this help?
I work as a tree pruner in the winter and have hugel'd all kinds of mixed up branches, seemed to work just fine. If you suspect that a certain annoying plant may develop adventitious roots in the pile, i would try to avoid it: some mountain ash branches that were sticking out of one of my piles actually leafed out and flowered last year because of the moisture inside the hugelbed.
leave any vines out to dry in the sun at least a week first.
you also want to throw in some forest leaf litter that is still moist. (and in the dark too).
you need to get some fungi in there to break down the antioxidants in the plant material, so the bacteria can make food out of the rest. the colors in leaves and branches are antioxidants, and will kill bacteria, so you need to start with fungi. they use them as food, and the leftovers go to the bacteria...
if you have palms, you should be burying, to use as soil water canteens, instead of piles. piles dry out quickly, which is why they were used in deep forest lands.
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