Understanding reforestation outcomes

The areas in need of post-fire reforestation far exceed the resources managers have for planting. It is critical to understand where tree planting is most likely to be effective at achieving restoration goals so that limited resources can be put to use most effectively. We surveyed regenerating vegetation in 5 fires that burned and were planted roughly 10 years prior to our surveys so that the planting outcomes had time to become apparent. We surveyed over 200 paired plots straddling planting unit boundaries to quantify the effect of planting – relative to natural regeneration – along environmental gradients. The data revealed, among other environmental influences, a strong effect of shrubs that varied from negative to positive depending on how soon after fire the seedlings were planted. We used the results to build a web-based management tool called PReSET that allows managers to predict reforestation outcomes and planting benefit across new wildfires that occur in Sierra Nevada mixed-conifer forests.