What is the controlled practice of burning undergrowth to promote the health of mature trees?

The controlled practice of burning undergrowth to promote the health of mature trees is known as prescribed fires or burning. This method involves carefully planning and executing fire events in a way that minimizes risks while enhancing the ecological health of forested areas.

Prescribed fires help to reduce the accumulation of dead and dry vegetation, which can lead to more intense wildfires if left unmanaged. By using fire in a controlled setting, land managers can improve habitat conditions for wildlife, encourage the germination of certain tree species, and promote a healthier forest ecosystem overall. The process also helps in nutrient cycling as the ash from burned plant material enriches the soil.

Other options like salvage cutting, thinning, and seed-tree cutting do not involve the use of fire in active management practices. Salvage cutting refers to removing trees that have been damaged or killed by pests or natural disasters, thinning involves selectively removing some trees to improve the growth and health of remaining ones, and seed-tree cutting is a method of timber harvesting that leaves certain trees for seed production. Thus, none of these practices directly correspond to the use of controlled burns for improving tree health.