California buckeye sheds leaves mid-summer as drought deepens

July 11, 2026San Francisco Peninsula

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across the Bay Area hills are dropping their leaves in July, their pale seed pods visible on naked branches while the oaks around them stay stubbornly green. On the same trees, you can see open flowers, mature fruits, and falling foliage all at once — a strange, unsettling combination that speaks to how this tree reads the calendar.

For the California buckeye, summer drought is winter. Rather than exhaust its water reserves fighting through the dry months, it simply goes dormant now, shedding leaves and waiting in a state of suspended animation until the rains return in fall. This strategy has served the species through millennia of Mediterranean climate, but as dry seasons lengthen, it's a calculation worth watching.

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