The home side eventually got their discipline right in the second stanza to score four more tries, first-five Tiaontin Raoren getting a double.
South Canterbury hosted winless King Country and battered them 72-0 in Timaru.
The home side scored 12 unanswered tries, with hooker Junior Faavae and winger Kalavini Leatigaga both getting doubles.
Also maintaining their unbeaten record and taking third place were Horowhenua-Kāpiti, but only just after they held off a brave East Coast 38-31 in a thriller at Levin Domain.
East Coast, desperate for that first Heartland win since 2013, have raised three bonus points in this campaign by pushing leading teams close, at home and away.
Again, the goalkicking of Horowhenua-Kāpiti halfback Jack Tatau-Robinson proved crucial with 13 points.
There was one upset in the round, or perhaps a re-establishing of the old order, as North Otago shook off last weekend's defeat to travel to Ashburton and upend Mid Canterbury 32-20.
Avenging their loss from 2020, North Otago were comfortably up 32-8 late in the piece, and although the home team rallied to score two more tries, it wasn't enough to secure a bonus point, and had them slip back to sixth on points differential among three other teams.
One of those teams is Poverty Bay, who continue to make the heavy Whanganui loss a distant memory after they beat West Coast 34-20 in Gisborne, with prop Toru Noanoa getting two tries.
Round three results, October 2
Thames Valley 30 (Tiaontin Raoren 2, Cameron Dromgool, Luke Masirewa, Trinity McQueen tries; Raoren pen, con) bt Buller 15 (Jesse Pitman Joass 5 pen). Halftime: 15-8 Buller
Horowhenua-Kāpiti 38 (Bryn Gordon, David McErlane, Benedict Grant, Lennix Tovo, Hamish Buick tries; Jack Tatau-Robinson pen, 5 con) bt East Coast 31 (Will Bollingford, Jody Tuhaka, Ngarohi McGarvey-Black, Teina Potae tries; Rapata Haerewa 3 pen, con). Halftime: 17-10.
North Otago 32 (Hayden Todd, Jake Matthews, Alipate Tuipolotu, Tristan Fuli tries; Josh Phipps 2 pen, 3 con) bt Mid Canterbury 20 (Adam Williamson, Raitube Vasurakuta, Seta Koroitamana tries; George Williams pen, Nathan McCloy con). Halftime: 24-8
Poverty Bay 34 (Toru Noanoa 2, Shayde Skudder, Penikolo Latu, Andrew Tauatevalu, George Whakatope tries; Tauatevalu con, P Manuel-Harman con) bt West Coast 20 (Ethan Simpson, Lewis Jackman, Steve Soper tries; Sean McClure pen, con). Halftime: 12-12
South Canterbury 72 (Junior Faavae 2, Kalavini Leatigaga 2, Sam Briggs, Vaka Taelega, Zac Saunders, William Wright, Conor Anderson, Zachary McKay, Sainivalata Ramuwai, Loni Toumohuni tries; Briggs 4 con, Wright 2 con) bt King Country 0. Halftime: 38-0.
