Dr Sigerson's translation was published in his book 'Bards of the Gael and Gall' 1907. Here is his text, from which it can be seen that there are numerous errors in the version posted above by Stewie, which he found in the Spooner/Farrell anthology:

Oft, at pleasant morning,
Sunshine all adorning,
I've heard the horn give warning
   With bird's mellow call––
Badgers flee before us,
Woodcocks startle o'er us,
Guns make ringing chorus,
   'Mid the echoes all;
The fox runs high and higher,
Horsemen shouting nigher,
The maiden mourning by her
   Fowl he left in gore.
Now, they fell the wild-wood:
Farewell, home of childhood,
Ah, Seán O'Duibhir a' Ghleanna
   Thy day is o'er !

It is my sorrow sorest,
Woe,–– the falling forest !
The north wind gives me no rest,
   And Death's in the sky:
My faithful hound's tied tightly,
Never sporting brightly,
Who'd make a child laugh lightly,
   With tears in his eye.
The antlered, noble-hearted
Stags are never started,
Never chased nor parted
   From the furzy hills.
If peace came, but a small way,
I'd journey down on Galway,
And leave, tho' not for alway,
   My Erinn of Ills.

The land of streamy valleys
Hath no head nor rallies––
In city, camp, or palace,
   They never toast her name.
Alas, no warrior column,––
From Cloyne to peaks of Colum,
O'er wasted fields and solemn,
   The shy hares grow tame.
O ! when shall come the routing,
The flight of churls and flouting?
We hear no joyous shouting
   From the blackbird brave;
More warlike is the omen,
Justice comes to no men,
Priests must flee the foemen
   To the mountain cave.

It is my woe and ruin
That sinless death's undoing
Came not, ere the strewing
   Of all my bright hopes.
How oft, at sunny morning,
I've watched the Spring returning,
The Autumn apples burning,
   And dew on woodland slopes !
Now my lands are plunder,
Far my friends asunder,
I must hide me under
   Branch and bramble screen––
If soon I cannot save me
By flight from foes who crave me,
O Death, at last I'll brave thee
   My bitter foes between !