Snopes verdict: false
Snopes - sequoia fact check
In addition to claiming that he had planted dozens of redwood and sequoia trees around Redondo Beach, California, GoblinsStoleMyHouse also maintained that he was “beginning to get older” and that the vengeful planting had occurred roughly three years prior after he was engaged in a homeowner’s dispute with the city. However, four months previously, he had described himself as a biology major (i.e., someone still in college), not an aging homeowner. Four months before that, the same user had mentioned living in a dormitory room “on a college campus” (not a residence maintained by a homeowner) in a separate thread. The user also freely discussed “trolling” fellow Redditors in mid-2017.
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Although the claims made in the original post about “Clyde,” sequoia/redwood trees, Redondo Beach, and petty revenge are not impossible, they are highly implausible. An arborist would know, for one thing, that giant sequoias and redwoods would not be able to grow at the rate described in Redondo Beach — or likely at all, given the historic drought that overtook southern California for several years until it officially ended in late 2016. Those trees, which once thickly carpeted all of North America, need quite a lot of groundwater (and, in the case of coastal redwoods, fog) to survive.
Mike Garcia, a state-licensed tree services and landscaping contractor who has lived and worked in Redondo Beach for half a century, told us that this story is impossible for a number of reasons. “Southern California is pretty much a desert. Where are all the sequoias located? North, in San Francisco where we get a lot of rain,” he said
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Coastal redwoods, Garcia told us, only grow in Northern California because of its higher coastal rainfall, a contrast with Southern California’s relatively arid Mediterranean climate: “I was born and raised in Redondo, I’ve worked in this town every single day, and I haven’t seen any sequoias or redwoods growing around here.”
He noted that if a tree were encroaching on a public sidewalk but growing on private property, the city would not uproot the tree but would instead perform what they call root pruning or root trimming: “They will cut the sidewalk out and they will cut the root out and lay the sidewalk again. Otherwise everybody’s trees would be torn out!”