It has the special combination of soil quality, location, growing season, and moisture supply needed to produce sustained high quality or high yields of a specific crop when treated 
(It; has; the special combination of soil quality, location, growing season, and moisture supply; T:when treated) (moisture supply; needed; to produce sustained high quality or high yields of a specific crop)
It moisture supply
has needed
the special combination of soil quality, location, growing season, and moisture supply T:when treated
to produce sustained high quality or high yields of a specific crop