Colonizing Freehold II

The floor of a valley on Freehold is:

"...covered...with a thick blanket of silvery-green trilobed 'grass' and sapphire blossoms."
-Poul Anderson, Captain Flandry: Defender Of The Terran Empire (New York, 2010), p. 27.

Anderson never fails to describe the local equivalent of grass on another planet. But there is another ground cover on Freehold:

"The path crossed a high hillside, smoothly graded and switchbacked, surface planted in a mossy growth so tough and dense that no weeds could force themselves in." (p. 38)

I do not find this clear. Is the growth planted on the path, the hill or both? In either case, this specially bred growth requires traces of manganese salt which are supplied by maintenance gangs who thus keep the "moss" within appointed bounds. The outbackers, calling themselves "the Free People," construct through the forest not a single broad highway but several small interconnected parallel roads which are:

easier to make;
enough for the traffic;
less ecologically or scenically harmful;
invisible from the air.

Other mutant plants are designed to mask human chemistry from technological surveillance. Outbackers do not conduct censuses but Karlsarm, war chief of the Upwoods, guesses a population of either forty or sixty million. (He guesses twenty million for his continent "'...and about the same for the others.'" (p. 39) There are two other continents but I do not know whether he means twenty million for each or for both together.)

I think that there are two other continents but I need to reread some more.