The competition saw the four provinces play each other in matchplay with all team members playing against their respective seeds. Whoever won over 18 holes earned their team a point, making the ties best of eight points.
An 8-nil win against Bay of Plenty the day before meant a win or a draw against Auckland would give Northland the shield. Auckland were up early in five of the eight matches but after nine holes it was an even split across the matches.
With four holes to play, Northland had notched up great wins from Squire and Kearns, who calmly slotted a 12-foot putt on the 18th.
When Northland captain Bonnington made a superb recovery on the 17th from behind a fairway tree to secure an excellent win, all that was required was one more win.
The task was left to Dale Clarke playing a 224-metre par three. Putting from 124 feet to within a foot of the hole, Clarke put pressure on his opponent who missed the 15-footer for par and saw Clarke complete the tap in and the victory.
"That was the pivotal moment so I was pretty lucky with that," Clarke said.
"I knew exactly what I needed to do, so it was a good thing and a bad thing."
Clarke, who flew out of Auckland to Australia yesterday to try to defend his Australian Mid Amateur golf title this week, said he was glad to see the talented Northland team reach its potential.
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"We rallied pretty late because we were a few matches behind, but we all dug deep and got stuck in so it was nice."
Brad Bonnington, who had competed for the shield for over 10 years with Northland, said it was great for the team to overcome the likes of Auckland, who had been strong nationally for the last four years.
"We had a good team on paper and obviously being [interprovincial] champions last year, that's given the team a bit of confidence, so I think we knew we had a good shot at winning it, we just needed to play well," he said.
With interprovincials set to start in two weeks, Bonnington said the form the team showed on the weekend put them in good stead to defend their title.
"It's good preparation for the interprovincials coming up, you get a good idea of the other teams and who they are looking at."
A four-man Northland junior team of Cole Allen, Aaron Allot, Tarrin Rous and Jack Hodgson also competed in Taupō for the Ralph Cup against teams from the same regions. Northland finished fourth with Auckland taking out the title.