Enhancing Juglans californica representation in ex situ collections from its most northerly range.

Project: Complete

In collaboration with United States Botanic Garden (USBG) and BGCI-US

Project Partner: Santa Barbara Botanic Garden (SBBG)

Juglans californica (California black walnut) is endemic to the coastal ranges of Southern California, with Santa Barbara and Ventura counties representing the northern extent of its range. The conservation of this northern population is increasingly important, as the effects of climate change are predicted to cause many plant taxa to move north in elevation. The genetics of northern populations of plant species are critical to help build climate resiliency.

This project is part of the North American Fruit and Nut Tree (NAFANT) Crop Wild Relative (CWR) Conservation Partnerships a collaboration between BGCI-US and USBG.

Project Goals

Preserve genetic material from northern populations of Juglans californica to help ensure robust genetic diversity is maintained in ex situ living collections. 

Key Achievements

SBBG successfully collected seeds from four northern populations of Juglans californica. All four of these populations were previously unrepresented in ex situ living collections. A total of 91 seeds were collected from 12 maternal lines.

The seeds are currently in cold stratification. When they are grown, many seedlings will be planted on suitable sites on the grounds of SBBG.

Seedlings will be shared with other regional gardens with significant California native plant collections, including California Botanic Garden and Descanso Gardens. Extra seedlings will be made available on PlantConnect.