Robert Foster states in his Lexicon (edit for brevity) So the general idea of mixing the
races seems confirmed.
And it's confirmed directly by
Tolkien in
Morgoth's Ring (that
Saruman interbred Orks with
Men).
In the Two
Towers Treebeard is talking about the
Uruks of
Isengard:
Treebeard is talking about Isengarders, yes; but is he necessarily talking about Uruks? I'll give the same quote a different emphasis in
bold blue (leaving your emphasis in bold black):
"For these Isengarders are more like wicked Men. It is a mark of evil things that came in the Great Darkness that they cannot abide the Sun; but Saruman’s Orcs can endure it, even if they hate it. I wonder what he has done? Are they Men he has ruined, or has he blended the races of Orcs and Men? That would be a black evil!"
Meaning, I'd say, Treebeard
wonders, but does not know.
However, the Ent strikes at the truth: Saruman
has mated Orks with Men. And I keep in mind, Treebeard says it was a good thing he'd heard the
hobbits before he saw them
" — if I had seen you before I heard you, I should have just trodden on you, taking you for little orks, and found out my mistake afterwards.". . .
. . . so in my opinion, the Ent could have easily mistaken
goblin-faced half-orks (see below) for Uruks.
____________________
In
Flotsam and Jetsam Merry described Isengard being "emptied". His description, in order:
1) Endless lines of marching orks, with some mounted on
wolves.
keeping in mind that Merry had already spent enough time among orks before saying this
Then. . .
2) Battalions of Men. . .
3) . . . and some of these "Men" were horrible:
"man-high, but with goblin-faces, sallow leering, squint-eyed"
And these remind Merry of the Southerner at
Bree,
"only that he was not so obviously ork-like as most of these were." Aragorn responds that many of these
"Half-orks" were at
Helm's Deep.
It seems to me, anyway, that we have some Half-orks who look enough like Men to serve as spies, and yet other Half-orks who were too obviously ork-like for that. Tolkien's choice of Ork-men and Men-orks (not
Uruk-hai in any case) to describe the
result of this interbreeding, is nicely, in my opinion, in line with this. . .
. . . that is, the
Men-orks being more
mannish, even some mannish enough to spy among Men, and the
Ork-men being more
orkish.
I note too that these were "Man-high" while even the
"huge ork-chieftain" in
Moria was
"almost man-high" according to the text. And the
Men-orks from
Morgoth's Ring get the description
large and cunning, while the Ork-men get: treacherous and vile.
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