Читать книгу The Trees of San Francisco онлайн

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That expertise is important because of the unique geographic and climatic conditions that make San Francisco a challenging environment for trees. The city’s climate is typically Mediterranean, with cool, wet winters and a long, cool dry season; the average high temperature in July is only 14°F higher than in January. Our location at the Golden Gate, a gap in California’s coastal range, adds even more unusual weather patterns. The summertime contrast between the cool, moist offshore air rushing through that gap and the warmer air rising from California’s inland valleys creates the city’s famous fog, as well as the sustained winds that make San Francisco the real Windy City (sorry, Chicago). If this weren’t enough, the topography here creates further challenges. The western neighborhoods closest to the ocean have the most wind and fog and, being built on former sand dunes, the sandiest (nutrient-poor) soils. The eastern, bay-facing neighborhoods are much sunnier, have better soils, and are less windy because they are sheltered by the hills to the west.