It would work, but the lower radials would have to
be spread apart to avoid coupling issues.
One could also just hang a second trap vertical as
the lower half of the antenna..
But, being I am a radio bully, I tend to avoid trap
antennas. Hustler verticals are pretty lossy on the
lower bands when you factor in the loss of the traps,
and then the upper level loading coil required to
resonate the thing.
If I were to use a commercial antenna to do what
you propose, I think I would prefer a Butternut over
the Hustler. :/
But anyway, what you want to do will work, but it
would be best to angle the radials a bit away from
each other to minimize coupling and the tuning
difficulties you would see if they are very close
to each other.
Also, the amount of ground loss will depend on the
antennas height in wavelength. So I wouldn't expect
gangbuster performance on the low bands unless the
antenna is very high. And how high must be determined
for each band measured in wavelength. High on 10m,
might almost be considered on the ground on say 80m.
So the amount of radials needed for an equal amount
of ground loss will very greatly to the frequency.
So if say the whip base is at 20 feet in the tree, and
you are hanging an 8ft radial for 10m, the performance
should be fairly decent. The antenna is up at nearly 3/4
wavelength, and one radial will do well.
But on 80m, 20 ft is just barely off the ground at
less than 1/10 WL high and the tree is not even tall
enough to hang it vertical. It would need to be run out
at an angle, and with only one radial at that low height
in WL, performance is going to be lame.
Of course, if you can mount it higher, the frequency
where lameness creeps in will slowly drop as you get higher.
:/
If I wanted to work all bands, I'd use the tree as a
support for an all band horizontal dipole.
Or even better, parallel fed full size dipoles, which
is what I usually run.
It would do a better job in the overall scheme of
things. You would have a semi decent NVIS pattern on
the low bands, and still be able to work some DX.
With stunted vertical on the low bands, NVIS performance
will be pretty lame. Many of the guys just running
plain Jane low coax fed dipoles will be kicking sand in
your face on the shorter lower band paths. :|