As the climate changes, cities scramble to find trees that will survive

Manzanita, with its peeling red bark and delicate pitcher-shaped blossoms, thrives on the dry, rocky ridges of Northern California. The small, evergreen tree or shrub is famously drought-tolerant, with some varieties capable of enduring more than 200 days between waterings. And yet here I was, gently lowering an 18-inch variety named for botanist Howard McMinn into the damp soil of Tacoma, a city in Washington known for its towering Douglas firs, bigleaf maples, and an average of 152 rainy days per year.

It’s not that I’m a thoughtless gardener. Some studies suggest that the Seattle area’s climate will more closely resemble Northern California’s by 2050, so I’m planting that region’s trees, too.

Climate change is scrambling the seasons, wreaking havoc on trees. Some temperate and high-altitude regions will grow more humid, which can lead to lethal rot. In other temperate zones, drier springs and hotter summers are disrupting annual cycles of growth, damaging root systems, and rendering any survivors more vulnerable to pests.

The victims of these shifts include treasured species from around the globe, including certain varietials of the Texas pecan, the towering baobabs found in Senegal, and the expansive fig trees native to Sydney. In the Pacific Northwest, I’ve seen summer heat domes turn our region’s beloved conifers into skeletons and prolonged dry spells wither the crowns of maples until the leaves die off in chunks.

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