As described in greater detail in Section A.8.1 of the CAPP (JMc 2013), Steven Singer delimited the boundaries of older-second growth forest within the Santa Cruz Mountains Redwoods CAPP Area based on analysis of stereoscopic images and additional existing data sources, including recorded harvest history records (Harvest_Records_All) Older-second-growth forests are operationally defined for the CAPP as stands of coast redwood (Sequoia sempervirens) and Douglas-fir (Pseudotsuga menziesii) with the dominant trees having a size (height and crown diameter) associated with a middle to late successional stage of development, and usually containing some residual old-growth trees (Singer 2012a,c).

To identify locations of such older-second-growth forests on unprotected private land , Singer used a Dietzgen 6x mirror stereoscope to examine stereoscopic images from the UC Santa Cruz Map Room at a scale of approximately 1:15,840. Singer delimited approximate boundaries of older-second-growth forests on USGS topographic quadrangle maps at a scale of 1:24,000. The stand boundaries were heads –up digitized by Jodi McGraw Consulting on a GIS featuring the corresponding digital raster graphics. Singer then reviewed the stand boundaries in Google Earth and JMc made minor modifications based on his feedback (Singer pers. comm. 2012).

All observed older-second-growth stands on unprotected, private lands within the CAPP Area were mapped except the following:

1. stands located within a residential neighborhood, and

2. stands less than 10 acres in size unless they came from a highly-reputable source or were in a constellation with other older second-growth stands nearby in which case they were mapped together.

As described in Section A.2.1, these data were integrated with the older-second growth stands (Older_Second_Growth_Forests) to create a composite layer of older forests (Older_Forests). This composite layer was then used to develop numerous components of the CAPP, including to identify sensitive habitats in the Vegetation layer and to map areas important for marbled murrelet (MAMU_Important_Areas).

As described in greater detail in Sections A.2.3 and B.1 of the CAPP (JMc 2013), the Older_Forests layer was used to characterize forest condition (Forest_Condition), which was one of 15 layers integrated in the conservation value analysis that was used to prioritize land for conservation as part of the CAPP. In this analysis, forests were scored in the following order of descending value: old-growth forest, older-second-growth forest, no recorded harvests, and one or more recorded harvests.

The CAPP GIS data were developed based on regional data and spatial analyses conducted primarily using available information. Site-level examination including on-the-ground assessments and surveys may be necessary to evaluate the occurrence of features depicted in this database, and refine conservation priorities identified in the CAPP.

References for data and literature cited in this description are available in the Santa Cruz Mountains Redwoods Conceptual Area Protection Plan Geographic Information System Metadata Report (JMc 2014), and can be obtained by contacting the Sempervirens Fund (see “Credits”).