GENETIC SYSTEM, VARIATION, AND ADAPTATION INESCHSCHOLZIA CALIFORNICA

Abstract

The perplexing variation and striking adaptability in the California poppy, Eschscholzia californica Cham., have long attracted interest. The present experimental study was undertaken to elucidate the causes of this polymorphism and ecological success. Techniques of mass sampling, growth of plants in more or less uniform conditions, and experimentation with breeding system have been employed to study the nature of morphological and physiological variation and to relate this variation to the reproductive behavior and environmental relations of the species. Eschscholzia californica is an annual or perennial herb of the family Papaveraceae. It is native in western North America from the Columbia River to Baja California and from the Pacific Coast eastward into the Great Basin. Within this area it grows at altitudes from sea level to 6,500 feet on open, well-drained soils of dunes, alluvial fans, river terraces, and hillsides. It is both widespread and abundant within its native region; man has extended its range by introducing it to Chile, New Zealand, Tasmania, and Australia, where it has become naturalized.