permaculture

[Toby Hemenway <hemenway@jeffnet.org>]

I saw some work in Northern California last week that might interest this
list. I was in the Sierra Nevada foothills east of Sacramento, which is
predominantly a mixed conifer forest. Because fire suppression has dominated
the philosophy of land stewardship in the US since we killed/drove off the
fire-using Native Americans in the 19th Century, the understory is a dense
thicket of manzanita and other sclerophyllous shrubs, 10-20 feet high and
mostly dead; in other words, a tinder box for catastrophic wildfire. Much of
the land is owned by US Forest Service and the Bureau of Land Management (or
Manglement, we usually say).

A fellow there has been working with BLM to imitate fire patterns in the
forest. They brought in an enormous rubber-tired machine from Idaho that's
essentially a giant chipper: a huge grinding wheel in front  grabs whole
shrubs (manzanita trunks can be 8-10 inches diameter) and spews out small
sticks and chips. They cleared the understory of several hundred acres this
way, leaving small and large trees intact, and creating a mulch layer 3-6
inches deep. Compaction seemed minimal except where the machine entered and
left the forest at roads; usually the tires made only one pass over a given
piece of ground. It looked very precise, as tiny seedlings were intact.

It does look like hell, initially, as though a giant flail had shredded the
understory, and it uses a lot of petroleum and weeks of labor to imitate
what could have been achieved with a single match (if the understory weren't
such a tinderbox, for a fire at this stage would kill everything). But
overall I'm very impressed. There's no smoke pollution from burning, no risk
of fire spread, and all that complex biomass ends up on the ground instead
of as smoke. It should really add to soil fertility, looks like ideal
insect, rodent, bird, and reptile habitat, and should green up nicely next
year and provide incredible browse for mammals. Plus the forest has that
savanna look that humans and many game animals like. Mulching the forest!

Interesting and encouraging project. If they do enough of this, maybe next
time they can just use a match instead of a big machine.

Toby