The 2011–2017 California drought persisted from December 2011 to March 2017 and consisted of the driest period in California's recorded history, late 2011 through 2014. The drought wiped out 102 million trees from 2011 to 2016, 62 million of those during 2016 alone. The cause of the drought was attributed to a ridge of high pressure in the Pacific Sea — the "Ridiculously Resilient Ridge" — which often barred powerful winter storms from reaching the state.