oak-woodland. South and west slopes are covered with chaparral. This distri- 
bution is largely due to differences in moisture availability. 
The chaparral on non-serpentine sites forms a dense shrubland 
dominated by chamise (Adenostoma fasciculatum). A number of other shrubs are 
associated with the chamise. There is virtually no understory beneath the 
shrub layer. Along the border of the chaparral with the grassland there is 
often a fringe of California sage (Artemisia californica) from one to three 
meters wide. The chaparral growing on serpentine is marked by a pronounced 
decrease in plant density. There is also a decrease in variety of shrubs 
present. The vegetation is dominated by chamise and leather oak (Quercus 
  
  
durata). Minor amounts of toyon (Photinia arbutifolia) and Ceanothus sp. 
  
are present. Soap plant (Chlorogalum pomeridianum) is abundant in the under- 
story. There is no fringe of California sage at the border with the grassland. 
Leather oak is largely restricted to the serpentine sites. It is a scrubby 
plant less than three meters in height. 
  
The grassland on non-serpentine sites is dominated by a number of 
introduced species. Except for soft chess (Bromus mollis), these introduced 
species are unable to become established on the serpentine. As a result, the 
serpentine grassland area has become a refugia for a wide variety of native 
prairie plants that are unable to successfully compete with the introduced 
species on the non-serpentine sites. Native plants on the serpentine grass- 
lands include perennial bunchgrasses and numerous flowering spring annuals. 
Image Analysis 
High altitude multispectral scanner imagery was acquired over 
Jasper Ridge on October 16, 1981 and on April 23, 1982 (Table 1). The two 
flights employed somewhat different spectral configurations. 
The vegetation conditions for the two image dates were quite differ- 
ent. In October, the grasslands were completely senesced and were brown, 
the chaparral was still dormant after the annual summer drought, and the oaks 
were damaged by a summer moth infestation. On April 23, the grasslands were 
at their annual peak in green biomass, the chaparral was actively growing, and 
the oaks had many new leaves. 
A serpentine unit was clearly visible within the oak-woodland as 
a canopy opening. The serpentine chaparral is distinctive from non-serpentine 
chaparral on the ground and discernable on the scanner imagery. It is also 
possible to distinguish the dense rim of leather oak and the sparse interior 
features of the main area of serpentine chaparral. These features form a 
spatial anomaly on the imagery that is not present anywhere else. 
+ 
The grassland sites show a dynamic phenological change between the 
two images. In the October imagery, when the vegetation on the grasslands 
had senesced, the visual difference between the two areas is faint. At the 
time the April imag ery was acquired, the serpentine grassland was carpeted 
with goldfield (Lasenthia californica), make it quite distinctive from the 
non-serpentine grassland (Figure 2). To examine the effect that flowering 
goldfields have on the imagery, training sets for both grasslands were extracted 
for the two image dates. The training sets were analyzed with stepwise 
  
‘discriminant analysis (BMDP-7M). While the bandpasses for image data for the 
two flights are not identical, there is a general correspondence that makes 
the comparison useful. The results for the analyses are given in Table 2. 
In the October imagery, the second green channel and an infrared 
channel were selected as being the most useful bands for discriminating the 
158 
  
two types. 
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Brooks, R. 
New York, F 
Clark, W. E 
County, Cal