Caldor Fire site in the Experimental Network for Assisted Migration and Establishment Silviculture (ENAMES)
The Caldor Fire site, part of the Experimental Network for Assisted Migration and Establishment Silviculture (ENAMES) study, has been established in the Eldorado National Forest to test assisted population migration of Douglas-fir, as well as the effect of planting configuration on seedling survival and growth. The site burned during the 2021 Caldor Fire and was planted in spring 2023.
Research Geneticist Jessica Wright looking at the plot map for the Caldor Fire site. Photo by Kara Sanghera.
Location: Eldorado National Forest, Placerville Ranger District
Nearest city or town: Pollock Pines, CA
Landowner: U.S. Forest Service
Species: Douglas-fir (Pseudotsuga menziesii)
Site history: The site burned in the 2021 Caldor Fire.
Site characteristics: The site is at an elevation of 5200 ft and faces southwest, with a slope of 10–15°. The soils are moderately deep, well drained gravelly sandy loams formed in material weathered from andesitic mudflows. The mean annual temperature is 51 °F (coldest month 37 °F, warmest month 69 °F) and mean annual precipitation is 1339 mm (76 mm as snow).
Planting date: Spring 2023
Contact person:
Luis Vidal, Manager, Northern California Forest Restoration, American Forests
Jessica Wright, Research Geneticist, Pacific Southwest Research Station
Christopher Looney, Research Forester, Pacific Southwest Research Station
The California ENAMES team preparing for the Caldor Fire planting. Photo by Kara Sanghera.
Management objectives and other considerations: TBA
Site preparation: None
Pre-planting site conditions: The site burned with high severity, leaving no live trees or snags and minimal woody debris. Some herbaceous groundcover had regenerated, but no natural tree regeneration.
Experimental design: Randomized complete block with four replications per assisted migration treatment by silvicultural treatment combination applied to 0.5-acre plots.
Assisted migration treatments: The team used the Climate-Adapted Seed Tool to choose four planted seed sources (see table below).
Climate period
| Seed origin | Seed source elevation (ft) | Mean cold month temperature (°C) | Summer heat-moisture index |
Historical/local (1961-1990) | Eldorado National Forest | 4500-5000 | 3.10 | 186.8 |
Early-century (2011-2040) | Eldorado National Forest | 4000-4500 | 3.96 | 212.6 |
Mid-century (2041-2070) | Eldorado National Forest | 3000-3500 | 5.23 | 274.0 |
Late-century (2017-2100) | Eldorado National Forest | 2500-3000 | 5.76 | 310.9 |
Seedling stock type: Containerized (Styro-6 for the historical, early-century, and late-century seed sources, Styro-91 for the midcentury seed source).
Silvicultural treatments: Planting configuration (rows vs clumps).
Monitoring: The site will be monitored to track and compare seedling survival and growth and pine blister rust infection among seed sources. We took initial measurements in the first year after planting, with follow-up measurements planned for 5, 10, and 15 years after planting.
The site may also serve as a demonstration plot for managers to visit and visually compare seed source performance.
Year 1 results
In the graphs below, bars with same letter (for example, a) indicate no significant difference among seed sources/climate scenarios. Different letters (such as a vs b) indicate a significant difference based on latest measurements.
Figure 1. Seedling survival for the different seed sources 1 year after planting at the Caldor Fire site.
Figure 2. Seedling diameter by seed source 1 year after planting at the Caldor Fire site.
Figure 3. Seedling growth by seed source 1 year after planting at the Caldor Fire site.