[Restorer]

I think the author is missing a major cause of the decline of the great forests of Eriador.

You'll have to forgive me, I don't have a reference book, so names and dates may be off.

According to the Silmarrillion, the Numenoreans used enormous quantities of timber to build their great fleets and for other purposes. Much of this came from Tharbad, or a city of another name at the same location.

The later, darker, Numenoreans lost all interest in proper stewardship of the great forests. They mined the forests, much as American loggers of the last century mined ours. And, as with ours, ancient forests may take a very long time to regrow.

Sauron himself may not have been heavily involved in the destruction of the forests of Eriador. If I remember correctly, he didn't have very long in the area before his army was destroyed.

[The Iguana]

Well said.

Tolkien discusses this at some length in the Second Age tales published in Unfinished Tales.

The two chief Numenorean foundations in the area were on the river Gwathlo (Greyflood) - the harbor Lond Daer (or Vinyalonde) at the mouth of the river, and Tharbad, farther up the river where the old road used to cross. From here they harvested timber far and wide in Eriador.

I am surprised that the usually thorough Martinez does not treat this development.