The History and Use of Cal Poly Land Spanish Exploration on the Central Coast of California

From Historical Atlas of California

The Spanish arrival initiated a period of cultural and environmental turbulence. First, they inadvertently introduced the seeds of old world weeds and grasses which were conveyed on their clothes and animals. These exotic plants proved hardier than many of the natives, and were well-adapted to the Mediterranean climate. Second, the impact of foreign germs brought with the Spanish decimated the Chumash population. Villages became sparsely populated, and traditional land management practices declined. The proliferation of non-natives and decline of traditional land management practices substantially reduced the overall range of the grasslands. As a result, the ecological balance shifted from one dominated by the Chumash to become vulnerable to the cultural and ecological changes from eventual missionization.