it was devastating, heartbreaking. everything had been incinerated. it was a field of the world s largest burned-up toothpicks. reporter: after decades of suppressing forest fire, other trees and brush have grown rampantly around the sequoias. the fires that used to burn every five to ten years in the sierra would just keep down the competition, and reduce the fuel naturally. reporter: on land owned by the save the redwoods league, we hiked out to see just how deadly the castle fire was here. for us to see 10 to 14% of the total of giant sequoias alive, killed in one year, in one fire, is there s nothing to compare that to. reporter: yet, fire, in and of itself, is not the enemy of the giant sequoia. their cones open up. their seeds start to germinate after a fire. reporter: so near those lost giants where the fire wasn t too intense, small chutes of hope take root.
take root. what i see have a lot of these baby giants that have sprouted up since the fire happened. without an urgent response to the climate crisis, and increased forest maintenance, experts worry more of the once seemingly impervious sequoias will be lost. the biggest worry for me is we have two fires burning right now that are threatening groves we have not been able to treat. the risk is still there. cnn in the sierra nevada mountains. and then there s the battle on the tennis court. the battle of the teens, in fact, in the u.s. open. women s final and the story of an 18-year-old qualifier who made tennis history dropping exactly zero sets along the way. subway®. has so much new it didn t fit it in their last ad. like this new and improved steak and cheese loaded with our new tender steak that s marinated and thicker sliced, on our new artisan italian bread. man, you covered up the footlong! the eat fresh refresh at subway®. it s too much new to fit in one commerc- t
naturally. reporter: on land owned by the save the redwoods league, we hiked out to see just how deadly the cassel fire was here. for us to see 10% to 14% of the total of giant sequoias alive killed in one year, in one fire, there s nothing to compare that to. reporter: yet fire in and of itself is not the enemy of the giant sequoia. their cones open up. their seeds start to germinate after a fire. reporter: so near those lost giants, where the fire wasn t too intense, small shoots of hope take root. what i see is a lot of these little baby giant sequoias that have sprouted up since the fire happened. reporter: without an urgent response to the climate crisis and increased forest maintenance, experts worry more of the once seemingly impervious sequoias will be lost. the biggest worry for me is we have two fires burning right now that are threatening groves that we have not been able to
year, there s nothing to compare that to. reporter: yet fire in and of itself is not the enemy of the giant sequoia. their cones open up, their seeds start to germinate after a fire. reporter: so near those lost giants where the fire wasn t too intense, small shoots of hope take root. what i see is a lot of these little baby giant sequoias that have sprouted up since the fire happened. reporter: without an urgent response to the climate crisis and increased forest maintenance, experts worry more of the once seemingly impervious sequoias will be lost. the biggest worry for me is we have two fires burning right now that are threatening groves that we have not been able to treat. the risk is still there. reporter: stephanie elam, cnn, in the sierra nevada mountains. up next, the girlfriend of an accused killer revealing new details about his state of mind just days before police say he shot and killed a three-month-old baby.