Competition

When you walk through a forest, it may feel like a static setting where very little is happening. But trees are constantly interacting and reacting to each other as they grow. There’s intense competition for light and space. Every shift affects the overall makeup of the forest in some way. Forest scientists like me spend a lot of time thinking about forest succession – a predictable process in which plant species colonize and dominate a piece of land. The basic sequence is for land to evolve from an open field to brush and shrubs, then to young trees and ultimately to large, mature trees. Disturbances, such as a major storm or wildfire, can interrupt or set back forest succession. I study ecological changes in species composition, tree arrangement and forest development that occur during succession and after disturbances. My research team analyzes conditions in mixed-species deciduous, or leafy, forests. Using tree rings, we reconstruct what previous forests looked l...

The planet is heating up as greenhouse gas emissions rise, contributing to extreme heat waves and once-unimaginable flooding. Yet despite the risks, countries’ policies are not on track to keep global warming in check. The problem isn’t a lack of technology. The International Energy Agency recently released a detailed analysis of the clean energy technology needed to lower greenhouse gas emissions to net zero globally by 2050. What’s needed, the IEA says, is significant government support to boost solar and wind power, electric vehicles, heat pumps and a variety of other technologies for a rapid energy transition. One politically popular tool for providing that government support is the subsidy. The U.S. government’s new Inflation Reduction Act is a multibillion-dollar example, packed with financial incentives to encourage people to buy electric vehicles, solar panels and more. But just how big do governments’ clean energy subsidies need to be to...