Quick answer: Seasonal Tree Care Checklist — Trees on this coast live with fog, salt, wind and thin soil, and the work that keeps them healthy is decided by those conditions rather than by a calendar written inland. Structure, clearance and the root zone are what a tree here needs looked at, and small work done early is what keeps a tree out of the emergency list.
Field note. What we see on this coast is that the trees people worry about are usually not the ones in trouble: the pine with a clean crown and a lean that predates the house is often sounder than the tidy tree that has been quietly drowning in its own root zone.
On the other hand, there is no schedule that suits every tree — the same species on two sides of one street can need opposite care, which is why we look before we recommend.
Tree care is not a set of tasks to be spread evenly through the year. Each season has work that belongs in it and work that must not be done in it, and the difference is mostly about what the tree is doing at the time.
Spring: watch, and don’t cut
The tree is spending stored carbohydrate on new growth. It has no energy to spare on sealing wounds, and the sap is moving. This is the worst season for structural pruning on most species.
What belongs here: an inspection as the leaves come out, because the crown’s density is most visible now and the leave-out pattern shows which limbs are dead. Water for anything newly planted. And a decision about what the season’s growth tells you — a tree that flushed weakly is a tree with a root problem.
What does not belong here: heavy pruning, fertiliser (it pushes soft growth into the wind), and any work on a wet-spring species like the pines.
Summer: water and nothing else
The dry season is the tree’s stress period. The work is water management: deep, infrequent irrigation for anything establishing, and none at all for established natives.
What belongs here: the dry-season window for oak pruning, because the wound seals fast and the wet-weather pathogens are not moving. Light structural work, deadwood, and clearance.
What does not belong here: planting, unless it can be watered reliably; and any grade change or excavation, because the roots are active and the soil is dry and fragile.
Autumn: inspect, plant and prepare
This is the busiest season and the most valuable. The rains are coming, the soil is cooling, and a tree planted now has months to root before its first summer.
What belongs here: planting, the pre-storm inspection (lean, ground at the base, unions, deadwood, drainage), and mulching before the rains so that the winter water infiltrates rather than running off.
What does not belong here: pruning an oak into the first rains, because that is exactly when the pathogen is dispersing.
Winter: structure and dormancy
For deciduous trees, the structure is visible and the tree is not working. This is the season for the structural decisions and for the pines, whose window is the cool dry period.
What belongs here: structural pruning on deciduous species, pine work, and stump grinding — the ground is soft and the access is easier without foliage.
What does not belong here: working on saturated ground with machinery, because compaction in winter is the damage that lasts. And pruning oaks in the wet.
The seasonal tasks that are not about the tree
Gutters, in autumn, because a gutter full of leaves is how a small branch becomes water damage. Drainage, before the rains. And the irrigation controller, in spring and autumn, because a programme set for July runs the same in October unless someone changes it.
The one thing that is year-round
Looking. The autumn inspection is the formal version, but the informal version — walking the property after a wind event and looking at the bases — is what catches the change before it becomes an event.