Inner Central Coast Ranges – Drought Effects on Native Plants

As this long dry summer comes to an end, we’re all reeling from four years of drought, but how are our Californian native plants affected by this extended dry cycle? Like most things in our state, the effects are variable with some species stressed and damaged while others are holding strong and even thriving.

This year, the CNPS Vegetation Program re-visited permanent plots in the Carrizo Plain to study the stability of vegetation in the area. This National Monument protects a variety of shrubland and grassland ecosystems that harbor several endangered plant and animal species. Our initial surveys occurred during the gorgeously showy (and wet) year of 2010 and now, five years later, we have recorded a distinct die-off of some shrubs within surveys of allscale (Atriplex polycarpa), spinescale saltbush (Atriplex spinifera), narrowleaf goldenbush (Ericameria linearifolia) and purple sage (Salvia leucophylla) shrublands. However, other vegetation types showed stability over this time period, such as California juniper (Juniperus californicus).

Though 2015 was quite dry, the timing of key rains in the inner Coast Ranges and southern San Joaquin Valley enabled showy displays of wildflowers. Some species, such as Eremalche parryi, bloomed in profusion and the Kettleman Hills supported more cover of native annuals than has been seen in years. Long-term monitoring at regular intervals can provide a rigorous scientific assessment of which habitats are vulnerable to shifts in climate. Additional study of the stability of vegetation types in California is sorely needed, in addition to the conservation of corridors to allow the movement of plants and animals within our ever-changing state.