Saint Mary's College Seasonal Swamp

Saint Mary's College Willow Seasonal Swamp (or Sausal) is approximately 14 acres in size. The site is the former Lake LaSalle (website construction started Spring 2009).

Aerial view of the Saint Mary's College Campus. The Red Willow Seasonal Swamp is the area dominated by trees in the middle of this photo.

Saint Mary's College plans to turn this seasonal wetland into a permanent "living laboratory" for both STEM and non-STEM majors (STEM: Science Technology, Engineering, and Mathematics). Faculty and students perform simple research projects currently on the site although access is strictly limited at this time. A few Environmental Science, Biology, and Jan term courses utilize the site for some field experiments, however greater utilization is planned for the future. The laboratory experiments and research projects are intended to be instructional without damaging the site.

The wetland has an extensive stand of red willow trees that were previously a rather common in the San Francisco Bay Area. This type of habitat has disappeared in general due to development, so this site is now rather unique. The wetland was formed because a dam was established on Las Trampas Creek and beginning in the 1950's the lake was no longer dredged, and the dam site eventually filled with silt. As the site filled with silt, vegetation colonized the site and red willows became the dominant along with giant horsetails.

In the three Jan term courses and many other courses, having a seasonal wetland on campus was a tremendous resource since the classes are able totake numerous field trips to observe the characteristics of a wetland without any significant travel challenges.

Class collected soil cores in the seasonal swamp which was rather dry in January 2009 and form the adjacent oak woodland to make comparisons of the soil characteristics. Student indicates the approximate size of core collected so far (photo by S. Bachofer)


January term 2008 class carefully hiked across the SMC swamp on the last day of class. The numerous streams were flowing rapidly due to recent rains. Heavy duty rubber boots were a necessity for this year. (photo by S. Bachofer).