Stewart, who played four one-day internationals for New Zealand in 2010, finished with figures of 5-42 from 12 overs with his gentle medium-pacers.
It was easily his best bowling in first-class cricket with his previous best of 3-17 coming earlier in the season.
Canterbury then proved there weren't too many demons in the pitch as they made their way to 128-1 at the end of the day with Peter Fulton unbeaten on 80.
The home side will look to pitch a tent at the crease tomorrow and bat Auckland out of the contest.
At the Saxton Oval in Nelson, Central Districts' bowlers got them off to a strong start on day one of their clash with Northern Districts.
CD are trying to wrap Plunket Shield honours and came in to the game with a small lead on the standings ahead of Otago.
Northern Districts lost the toss and were put in to bat this morning and were bowled out for 267, with the in-form Daryl Mitchell top-scoring with 72.
The 21-year-old made his maiden first-class hundred in the side's last outing against Wellington last week and is finishing the Plunket Shield in strong touch.
Mitchell found support from veteran ND batsman James Marshall who added 54, while CD paceman Ben Wheeler picked up 3-35.
At the close of play, CD had made their way to 46-0 with openers Jamie How (17) and Jeet Raval (27) at the crease.
At the Basin Reserve, Wellington's mixed season continued as they only mustered 255 in their first innings after losing the toss and being put in to bat by Otago.
Opener Michael Papps made 63 for the Wellingtonians as he and opening partner Josh Brodie (37) put on 99 for the first wicket but the rest of the side failed to take advantage of the solid platform they were given.
Otago all-rounder Jimmy Neesham was the pick of the bowlers with 3-39, while Neil Wagner and Ian Butler each picked up two wickets.
Otago closed day one on 113-2 with opener Aaron Redmond unbeaten on 60, while night watchman extraordinaire Nick Beard was at the other end on nine.
Beard made 188 as a night watchman in his side's last Plunket Shield outing against Auckland and will be hoping for another long stay at the crease tomorrow. (Thurs)