The colossal General Sherman Tree in Sequoia National Park's Giant Forest, some of the other sequoias, the Giant Forest Museum and other buildings were wrapped as protection against the possibility of intense flames, fire spokeswoman Rebecca Paterson says.

The aluminum wrapping can withstand intensive heat for short periods. Federal officials say they have been using the material for several years throughout the US west to protect sensitive structures from flames.

The Colony Fire, one of two burning in Sequoia National Park, was expected to reach the Giant Forest, a grove of 2000 sequoias, on Thursday.

It comes after a wildfire killed thousands of sequoias, some as tall as high-rises and thousands of years old, in the region last year.

The General Sherman Tree is the largest in the world by volume, at 1487 cubic metres, according to the National Park Service. It towers 84 metres and has a circumference of 31m at ground level.

Giant sequoias are adapted to fire, which can help them thrive by releasing seeds from their cones and creating clearings that allow young sequoias to grow. But the extraordinary intensity of fires - fueled by climate change - can overwhelm the trees.

That happened last year when the Castle Fire killed what studies estimate were 7500 to 10,600 large sequoias, according to the National Park Service.

A national interagency fire management team took command of efforts to fight the 30 sq km Paradise Fire and the 8 sq km Colony Fire, which was closest to the grove. The fires forced the evacuation of the park this week.

The wildfires are among the latest in a long summer of blazes that have scorched nearly 9195 sq km in California, destroying hundreds of homes.

Australian Associated Press