Fall is the most useful season for tree care in Clark County, and most homeowners spend it raking. Between September and November you get three things at once: leaves drop and expose structure you could not see all summer, the soil rewets enough for roots to establish, and you still have time to deal with problems before the first real windstorm.
Here is the short version of what to do, in the order it matters.
Walk your property and look up
Do this once in early October, after most leaves have dropped. You are looking for things that are obvious once the canopy is bare:
- Dead limbs still hanging in the canopy. These are the ones that come down in the first storm, and they land wherever gravity says.
- Splits where two trunks meet. A V-shaped union with bark pinched inside it is a structural defect, not a quirk.
- Lean that looks new. Old lean with straightened growth at the top is usually fine. Fresh lean with cracked or heaved soil on the opposite side is not.
- Mushrooms or shelf fungus at the base or on the trunk. Fall is when these fruit, which makes it the only season you reliably see them.
If you find any of the last three, that is the point to get a professional hazard tree assessment rather than guessing.
Deal with storm risk before the storms
Clark County gets its damaging wind between late October and February, usually arriving with saturated ground already in place. That combination is what actually brings trees down here — not wind alone, but wind against roots sitting in soft, waterlogged soil.
Anything you want removed or reduced before winter should be scheduled in September or early October. Once the first big system hits, every tree company in the county is running emergency calls and the schedule for planned work stretches out.
Plant now, not in spring
Fall is the better planting window in the Pacific Northwest. A tree planted in October spends the entire wet season growing roots in cool, moist soil with no heat stress and almost no watering required from you. The same tree planted in April has a few weeks to establish before it has to survive its first dry August.
Plant while soil is still warm enough to work, generally through November.
Hold off on most pruning until dormancy
The urge to prune in fall is understandable and mostly wrong. Structural pruning is best done when the tree is dormant, roughly December through February, when the architecture is fully visible and the tree is not spending energy on active growth.
Two exceptions worth acting on now: remove anything dead, broken, or clearly hazardous whenever you find it, and clear limbs that are actively rubbing a roof or blocking a driveway. Everything else can wait for dormant-season pruning.
Leave the leaves, mostly
Leaf litter under the canopy is free mulch and it feeds the soil your tree is living in. Rake what falls on lawn and hardscape, and let what falls in beds and around trunks stay where it is.
One exception: if a tree had a leaf disease this year, with spotted, blotchy, or early-browning foliage, rake and remove those leaves. Many foliar diseases overwinter in fallen leaves and reinfect the tree next spring.
Skip the fall fertilizer reflex
Most established trees in Clark County do not need fertilizer. Our soils are generally adequate, and feeding a stressed tree does not fix the reason it is stressed. If a tree is thinning, discoloring, or losing vigor, the cause is usually root damage, compaction, drainage, or decay, and fertilizer treats none of those.
If a tree genuinely looks unwell, get a diagnosis first. That is what plant health care is for.
What this looks like month by month
- September: Schedule removals and major work. Walk the property. Water anything planted this year until the rains take over.
- October: Plant new trees. Do your bare-canopy inspection. Get hazard trees handled.
- November: Finish planting. Clear diseased leaf litter. Confirm nothing is resting on the roof before the wind arrives.
Cascade Tree Works serves Vancouver, Battle Ground, Camas, Brush Prairie, La Center, Washougal, Ridgefield, and Hockinson. Our ISA Certified Arborists can look at your tree and tell you plainly what it needs. Request a residential estimate.
