Do all my trees have to come out for defensible space?

What the guide says about clearing everything

Living With Fire states that removing all vegetation is not good for ecosystem health and can lead to more invasive weeds and grasses, cheatgrass among them. It also says its guide does not replace an in-person inspection, which your local fire agency can arrange free of charge in many places.

So the question is never trees versus no trees. It is which trees, how far apart and how high the lowest branches hang.

What usually goes first

For Zone 2, the guide says to remove weakened, damaged or dead trees before healthy ones, clear dead material, and eliminate ladder fuels such as shrubs, lower branches and small trees under the drip line. It adds a limit: do not remove more than one-third of a tree's branches, because that hurts the tree.

Closer to the house the rules tighten. In Zone 1 the guide says to trim branches within 10 feet of the home, chimney, deck or roof and within 10 feet of other trees. Zone 0 is the strict one: no woodpiles, no wood mulch and no flammable shrubs, with junipers, mugo pine, Austrian black pine and arborvitae named among the plants to remove.

Which ones the arborist keeps

A healthy, well-spaced pine or fir 60 feet from the house often stays. A dead one, a crowded stand or a tree overhanging the roof often goes. The arborist makes that call at the visit, and you can see the reasoning on the estimate. We can cable or prune a tree you want to keep when its structure allows.

At Lake Tahoe a live tree over 14 inches across needs a permit before it comes down; the fire district or TRPA handles that. For the thinning method, see ladder fuels and limbing up.