Germination Characteristics of Engelmann Oak, and Coast Live Oak from the Santa Rosa Plateau,

Abstract: Over 2,000 acorns of Quercus agrifolia (coast live oak) and over 500 acorns of Q. engelmannii (Engelmann oak) were collected in the Jim Knight pasture area of the Santa Rosa Plateau. These were used to test for temperature and moisture conditions on germination of viable acorns in the laboratory under controlled environmental conditions. At 24°C Q. engelmannii had almost 90 percent germination after 6 days, while Q. agrifolia had about 20 percent (96 percent after 20 days). At 14°C completeness and speed of germination of Q. engelmannii was reduced to about 80 percent after 36 days, while Q. agrifolia had over 90 percent at 30 days. At 4°C Q. engelmannii had about 60 percent germination at 72 days, while Q. agrifolia had over 90 percent at 72 days. At varying degrees of moisture stress from field capacity to-100 bar atmosphere (at 20°C) Q. engelmannii had at least 70 percent germination o