Trying to determine the impact of the drought….
Check this out:

Some of the Earth’s largest and longest-living trees, the Giant Sequoias, could be at risk of dying due to California’s worst drought in more than 1,200 years, according to scientists.

However, environmental researchers in Northern California are taking their concern to new heights by scaling 50 of them in Sequoia National Park to determine the four-year-old drought’s impact on the trees.