Head of planning and environment Michael Pittock said: “It is devastating to walk around the area of the wildfire and see so much destruction.
“Without the remarkable response from the fire and emergency services it could have been so much worse.”
Several centuries-old trees have been lost, as the fire penetrated their root systems, Forestry England said.
Bogs, normally resilient to heat, have been burnt and partially destroyed, it added.
The lost vegetation includes pillwort, a rare wetland plant with a New Forest stronghold.
