High-intensity chaparral fires cause increased erosion and sediment transport into streams, and this can be seen in the thick black sludge filling the Cold Creek channel. On my December visit, with no recent rain, the creek bed was pretty dramatically full of sludge.
December 30, 2015:
By my January visit, several small storms had contributed to small flows in the creek. As water washes the runoff from the burned hillsides through the system, ash from the fire as well as contaminants that were present on the hillsides will move through Cold Creek and into Putah Creek. This creates water quality concerns which will be addressed by future water quality monitoring to be conducted by the Solano County Water Agency.
January 8, 2016:
While the Cold Canyon trails are closed, the reserve is offering guided hikes to the public (current list of hikes). I participated in a hike at the end of December, led by Jeffrey Clary, Stebbins Cold Canyon Reserve Manager. We walked along the canyon trail, discussing the plants that were started to regrow, and how the site is faring five months after the fire.
Interestingly, there is less regrowth at this point than might be expected, with the hillsides still quite bare, with many fewer seed regenerating plants than after similar fires. That is not to say that there is no regrowth yet, though, and hikers found plenty of interesting plants along the trail, growing from seeds, bulbs, and resprouting from stumps.
We also observed other effects of the fire, including many new rock faces, created when the water inside the boulders caused them to explode in the heat of the fire.
Due to extensive damage to the trails and the overall sensitivity of surviving plants and wildlife at the reserve, the Cold Canyon trails are closed until at least spring 2016. In September, I visited the reserve’s closed trailhead, to take a look at the landscape and to document the trail closure. Looking through the chain-link fence, I could see charred ground and skeletal trunks of trees and shrubs, but noted that the signpost was left unscathed.
The Wragg Fire started just over the ridge to the west of Cold Canyon, rushing quickly over the hill and down into the canyon. Once there, it remained in the canyon, generating winds that caused it to cycle within the canyon, according to Jeffrey Clary, Stebbins Cold Canyon Reserve Manager. This greatly increased the intensity of burning in the canyon. The differences in fire intensity across the landscape burned will lead to interesting opportunities to compare rates and types of regrowth in the coming years.
Between July 22 and August 5, 2015, the Wragg Fire burned over 8,000 acres in Napa and Solano Counties, including the entirety of the Stebbins Cold Canyon Reserve near Lake Berryessa.
On July 28, driving home in Davis, I happened to notice a new large plume of smoke, further south than where I had seen smoke previously. This was the day the fire reignited, after having been at 80% containment. It took another seven days to reach full containment.
As I stood at the side of the road watching, an air tanker flew overhead, heading away from the fire.
A couple of days earlier, I had seen the completely burned hillside west of Winters, making a stark contrast with the hills in their usual summer gold and green to the north.