Stumbled on a stat about tree root spread and it's messing with my head

I was reading through a drought study from UC Davis last night, and it said the root system of a mature oak can extend 2-3 times the canopy width. For real, most of the roots are in the top 18 inches of soil too. That makes me wonder if we are all digging our planting holes way too deep or narrow, especially in clay soil around here. Has anyone else tried shallow wide planting vs the traditional deep hole method?

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alicecooper1mo ago

Switched to wider shallower holes a few years back after killing a couple trees in heavy clay. Roots spread way better and the trees actually took off faster than the deep ones.

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kimr101mo ago

Huh, that actually makes a ton of sense now. I've been digging those deep holes like they tell you to on the bag and then wondering why my trees just sit there for months.

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