The Rim Fire has threatened two groves of giant sequoias that are unique in the region, prompting park employees to clear brush and set sprinklers around the huge trees.
While sequoias have a chemical in their bark to help them resist fire, they can be damaged when flames move through slowly.
More top news
Protestors angry about an immigration raid at Byron burger earlier this week reacted by launching hundreds of insects into the restaurant
Families and rebel fighters are believed to be among the people to have left besieged Aleppo on Saturday through safe corridors.
The balloon came down near Lockhart, Texas, around 8.30am local time.