Reducing forest cover to about what it was before the 1990s would increase water yield and could be seen as restoration of more natural forests.

That was one take on the WWALS Webinar by Dr. Matthew J. Cohen, presenting research about forest management to lower Leaf Area Index (LAI) and increase water yield, on May 28, 2026, from noon to 1 PM.

Video: Leaf Area Index and Forest Water Yield, Dr. Matthew Cohen, WWALS Webinar 2026-05-28

Leaf area index (the ratio of leaf cover to ground area) increased in the 1990s. Reverting to about the LAI before then would increase water yield into streams and wetlands, and thence into the Floridan Aquifer. This works by reducing evapotranspiration from the trees.

LAI can be decreased through means such as delaying replanting after clearcutting, not planting as densely, and thinning more or sooner. The resulting increased waterflow is as clean as any source.

Unlike the agriculture that is the subject of the Basin Management Action Plans (BMAPs), forestry does not irrigate.

The research is quite thorough and Dr. Cohen indicated more potential effects.

Here is the zoom video:

https://youtu.be/_PTxZJ6BJFw Continue reading →