Douglas Fir and Ponderosa Pine Regeneration in a Changing Climate

Observation by Dylan Tripp:

In the Interior Cedar Hemlock dry warm subzone, I've observed that sites historically dominated by Douglas fir, western larch, and lodgepole pine and harvested 3-7 years ago are showing a decline in Douglas fir due to drought, with slower growth and increased mortality. This is in contrast to the thriving ponderosa pine. These insights, which I'm sharing with the LEO Network, suggest that current reforestation standards may be inadequate, potentially jeopardizing forest health. Factors like reduced summer precipitation, extreme heat events, and ponderosa pine's superior drought resilience highlight the need to adapt reforestation practices to species more suited to changing environmental conditions. In consultation with experts, the consensus was that Global Climate Model's still predict these ecosystems to favor Douglas fir for the next 50+ years, begging questions surrounding site classification, proper species selection and appropriate seed selection in the initial prescriptions. I was able to confirm in the field these factors were prescribed appropriately. My observation of local environmental changes, particularly in forestry, aligns with broader issues identified by the UNEP (2019), like land use change and habitat loss. These changes, alongside agriculture, mining, and dam projects, contribute to detrimental cumulative effects like terrestrial ecosystem decline. These industries aren't harmonized at provincial, let alone global levels. The inability to successfully reforest my observed site due to changing conditions, while seemingly minor, could foreshadow significant future challenges at provincial, national, and international levels.

Comment from LEO.ai:

The resilience of different tree species to drought and extreme weather events is a critical factor in forest health and sustainability. This observation supports the need for adaptive management strategies that consider the long-term viability of tree species under changing climatic conditions. It is essential to integrate local observations with predictive models to ensure that reforestation efforts are both ecologically appropriate and resilient to future climate scenarios. The UNEP report cited highlights the global nature of these challenges, emphasizing the importance of local actions for environmental stewardship. As we move forward, it will be increasingly important to align local forestry practices with global sustainability goals, ensuring that reforestation efforts contribute positively to ecosystem health, carbon sequestration, and biodiversity conservation.

Reference: United Nations Environment Programme (UNEP). (2019). Global Environment Outlook – GEO-6: Healthy Planet, Healthy People. Cambridge University Press. Link