Each mule in the pack string carries 150 pounds of supplies to restock firefighters sleeping and eating in the remote Sespe area.
The pack strings head out from a trailhead in Rose Valley early each morning and return in the afternoon.
Wilderness designations protect special areas of the forest, and motorized or mechanical transportation is generally not allowed.
The fire 11 miles north of the city of Ojai has burned nearly 3 square miles since June 30. More than 660 firefighters were on the lines Tuesday and the blaze was 15 percent contained.
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