Is Tolkien's "maggot-folk of Mordor" describing or identifying?

Question

In Book V of The Return of the King, in "The Black Gate Opens," as the Captains approach the Gate, Tolkien makes this statement (phrase in question bolded by me):

North amid their noisome pits lay the first of the great heaps and hills of slag and broken rock and blasted earth, the vomit of the maggot-folk of Mordor; but south and now near loomed the great rampart of Cirith Gorgor, and the Black Gate amidmost, and the two Towers of the Teeth tall and dark upon either side.

North of the Black Gate is actually outside Mordor, but obviously the landscape north of it was affected by these "maggot-folk of Mordor." The question I have specifically is if "maggot-folk" is merely a general, descriptive, collective term referring to all the various "peoples" of Mordor (orcs, trolls, evil men, etc.) or is there some evidence in other writing that Tolkien is here making an identification of a specific people group that were part of Mordor who terraformed the landscape in such a destructive way?

Answer 1

Probably orcs

"Maggots" suggest creatures that are small, which would rule out Trolls and the large Uruks of Mordor.

The closest I can come to a quote that answers your question is when Frodo and Sam approach the Black Gate.

Across the mouth of the pass, from cliff to cliff, the Dark Lord had built a rampart of stone. In it there was a single gate of iron, and upon its battlement sentinels paced unceasingly. Beneath the hills on either side the rock was bored into a hundred caves and maggot-holes; there a host of orcs lurked, ready at a signal to issue forth like black ants going to war.

_{The Lord of the Rings Book 4, Chapter 3: The Black Gate is Closed}

This could be said, by analogy, to equate orcs to maggots (as well as to ants).

There are also plenty of places where orcs refer to each other as "maggots". This includes during the arguments between Saruman's Uruk-Hai and the smaller orcs of the Misty Mountains.

In the afternoon Uglúk’s troop overtook the Northerners. They were flagging in the rays of the bright sun, winter sun shining in a pale cool sky though it was; their heads were down and their tongues lolling out.

‘Maggots!’ jeered the Isengarders. ‘You’re cooked. The Whiteskins will catch you and eat you. They’re coming!’

_{The Lord of the Rings Book 3, Chapter 3: The Uruk-Hai}

On the whole, I think it most likely that Tolkien had orcs (the smaller breeds rather than the larger Uruks) in mind when he referred to the "maggot-folk of Mordor".

Answer 2

I would say maggot-folk of Mordor are Uruk-hai. As written on LOTR wiki

The Uruks first appeared about the year TA 2475, when they conquered Ithilien and destroyed the city of Osgiliath. The Uruks in the service of Barad-dûr, the folk of Mordor, used the symbol of the red Eye of Sauron.

Also the is descripition

Sauron's uruks, seen in The Return of the King, have noticeably rougher features than Saruman's. They are shown in the movie as being released from a kind of membrane in the mud deep under Isengard (special commentary on the DVD edition explained that they were trying to base the scene on an early description of Tolkien's that orcs "worm their way out of the ground like maggots")