CLAYTON (KCBS) — The Morgan Fire that has burned more than 3,133 acres reached 90 percent containment Thursday morning and firefighters expect to have it fully contained by Friday.

Rangers at Mt. Diablo State Park began rehabilitation and cleanup work before winter rains threaten to erode the mountainside.

Brush that squirrels and smaller animals once hid under was gone, making them easy prey to predators including mountain lions and Red-tailed Hawks.  The assessment of what burned and how quickly it can come back was underway.

Park Ranger Dan Stefanisko said grasslands and woodlands burned, but not too many structures.

“As far as I know, maybe some restrooms, some picnic areas, a couple of tables,” he said.

Much of what burned was on the southeast side of the park, which is rugged and remote offering popular trails for people who like to get away. Those will have to be evaluated for safety before re-opening to the public.

The last time there was a large fire on Mt. Diablo was in 1977; after that the mountain was covered in orange poppies and yellow golden ear drops, wildflowers that only grow after intense fires according to naturalists.

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