Saltus versus silva

I just learned a new latin word: saltus - a wooded pasture, forest, upland.

Does anyone know how saltus differs from silva in usage?

Ago tibi,
Rob Carignan

It’s mountain forest

From Döderlein’s Hand-book of Latin Synonymes:

Silva > (ὕλη) denotes a wood, in a general sense, merely with reference to the timber, like ὕλη; whereas > saltus > (ἄλσος) as a wild place, or wood in the midst of mountains, like νάπη

The synonymes of the Latin language, Hill (1804): sylva, nemus, saltus, lucus.

P.S. Here are computer dictionaries of Latin synonyms.