La Costa Canyon Fire Succession Study

Figure 1. An aerial photograph taken in January 1997 shows a portion of the area that burned in the Harmony Grove fire of October 1996. The yellow polygon represents the transect boundaries of the study site.

Figure 2. This is a visual representation of the perimeters of the dominant species and their location within the test site. These plants are representative of the coastal shrub community that predominates after fire. An aerial photograph taken in the spring of 1998 underlies the student-collected data from April 1998. Deerweed is the indicator species of this ecosystem. Black mustard, a highly invasive non-native, is being tracked because it interferes with the growth of native species and is highly flammable. Research suggests that this primary community may be succeeded by species like the sages that are indicative of chaparral.

Figure 3. An aerial photograph taken in the spring of 1999 1998 underlies the student collected data from April 1999. The 1999 data shows that there is more plant diversity than the previous year. The bushmallow, although represented as a large mass, is in fact interspersed with many other plant species. There has been an overall increase in the extent of the bushmallow on the south-facing slope and a decrease in the overall extent on the north-facing slope. Deerweed is still a commonly encountered species, but there are no longer areas where it is dominant. Last year there was a great deal of Black Mustard, but it is almost non-existent in the site area this year. The Laurel sumac on the west-facing slope has spread and it appear to be heading towards dominating that slope.