Great covering defence from halfback Malcolm McLeod save Northland when Mike Molloy went for the left corner post, while Wisea Lawebuka stopped a rampaging Brayden Mitchell on the opposite flank.
However Southland finally broke the scrambling defence, with centre Jaye Thompson sending Molloy through in the 23rd minute.
An opportunistic kick and a lucky bounce brought Northland back into the contest as fullback Solomon Alaimalo put through a grubber in Southland's half. Peter Breen picked up the fortuitous bounce to square the ledger.
Southland's Wharenui Hawera struggled with the breeze in the first half, missing multiple opportunities to put his team in front.
Kite was in the thick of the action throughout the first spell, popping up to provide probing runs and the odd deft pass.
Northland had a chance to take the lead right at the end of the half but fell victim to a reliance on one-off ball runners, leaving the score tied going into the sheds.
Breen once again stood out for the Taniwha, directing his troops well and utilising his incisive running game.
A leg trip from Shane Neville immediately gave Hawera a chance to put Southland back in the lead with a penalty goal 40 metres out.
Northland then spent the next ten minutes hammering the Southland line, but the Stags held on valiantly.
For a while it looked as if Southland's scrum, lineout and goal line defence were impregnable with Northland unable to find any chinks.
But in the end the gave in, with Neville paying his side back with a conversion next to the uprights.
Southland scored immediately after in comical fashion. Halfback Jimmy Cowan thought he was milking a penalty and attempted a drop goal to get the ref's whistle. However there was no advantage and the kick sailed between the uprights.
Hawera then made the Taniwha pay of lackadaisical defence as he shot through virtually untouched for a converted try.
Southland started to take advantage of Northland's reversing scrum and spent plenty of time inside the red zone.
That time resulted in more points as Northland's defence wavered in the latter stages of the contest, allowing Tauasosi Tuimavave to ghost through the line.
Schrader then beautifully read a cut out pass from Breen to run away for an intercept try to effectively end the contest with seven minutes to go.
The try took nearly 10 minutes to award after the TMO mulled over a scuffle where nothing much happened.
After the unexpected break, replacement flanker Aorangi Stokes capped off a good break from Warren Dunn to give Northland the try scoring bonus point.
Jone Macilai then scored a try as Northland went down with a fight.
Northland round off their season with a home match against North Harbour on Sunday, while Southland travel to Tasman.
Southland 39 (James Schrader 2, Mike Molloy, Wharenui Hawera, Tauasosi Tuimavave tries, Hawera con, pen, Greg Dyer 2 con, Jimmy Cowan dg)
Northland 31 (Phil Kite, Peter Breen, Shane Neville, Aorangi Stokes, Jone Macilai tries, Breen 3 con)
HT: 12-12