Читать книгу Afoot & Afield: Orange County. A Comprehensive Hiking Guide онлайн

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Native Gardens

About 800 different kinds of wild flowering plants are found within Orange County’s 782 square miles, a remarkably large number considering its diminutive size among California counties.

There are two reasons for this abundance of plant species. One reason has to do with physical factors: topography, geology, soils, and climate. Countywide, the diversity of physical factors and the complex interrelationships among these factors have led to the existence of many kinds of biological habitats.

The second reason is Orange County’s location between two groups of flora: a southern, drought-tolerant group, most clearly represented by various forms of cacti; and a northern group, represented by moisture-loving plants typical of California’s northern and central Coast Ranges. As the climate changed, varying from cool and wet to warm and dry over the past million years or so, species from one group and then the other invaded the county. Once established, many of these species persisted in protected niches even as the climate turned unfavorable for them. Some survived unchanged; others evolved into unique forms. Some are present only in very specific habitats.