Ho fatto una ricerca in linea e non ho trovato il corrispondente inglese di tramarratura o succisione. Per cui concorderei in generale con la tua traduzione....con piccoli cambiamenti:

"... can be performed 5-20 cm [2"-4"] from the ground (salvage felling above ground), even with the ground (salvage felling at ground level) or a few centimetres [inches] below the ground level (salvage felling below ground)".

Io userei proprio "salvage felling", che credo sia diverso da "felling".

Vedi sotto:

Whether you are using your chain saw to cut firewood, trim trees or harvest large timber, you will be performing three basic operations — felling, bucking and limbing of trees. Felling involves cutting the standing tree and dropping it in the place you want it. Limbing is the removal of the branches from either standing or downed trees. Bucking is the process of cutting the downed tree into appropriate lengths.

http://muextension.missouri.edu/xplor/agguides/agengin/g0195...

Rehabilitation of burnt forest is done to reactivate its economic, ecological and social functions. If the dead wood in the burnt area is valued as viable for production, then the area can be used for salvage felling, for rules on harvesting under salvage felling conditions please refer to :

http://www.iffm.org/sfmp/m@in/eng/en-rehab.htm

Mi pare che la tramarratura e la succisione siano operazioni di recupero (salvage felling), mentre "felling" sia semplicemnte taglio.

Buon lavoro.
Ciao,
M.