The big win means they and second-placed Crediton cannot be caught by anyone else in the Cornwall/Devon League.
However, the title is still to be decided. The teams are locked on 108 points with three games to go.
The pair meet on the final day of the season when the title is almost certain to be decided.
Crediton overcame OPMs 59-0 at Elburton to keep pace with the Ashes.
There was also joy for Plymouth Argaum, who have guaranteed themselves a top two finish in Devon One with a 34-20 away win at Old Techs.
They just need two more points to guarantee a second successive title and promotion.
Second-placed Plymstock Albion Oaks and third-placed St Columba & Torpoint kept up the pace with wins over Wessex and New Cross respectively.
Argaum sit on 57 points at the top of Devon One, Oaks on 49 and St Columba 44 with two matches to go.
Ivybridge also took a massive step to guarantee a play-off place in South West One.
The Bridgers, who sit second, beat third-placed Bridgwater & Albion 31-26 at Cross-in-Hand. They took hold of the match in the first half and led 21-9 at the break.
They are now 10 points ahead of Bridgwater with three games to go.
However, things do not looks as bright for Tavistock, who are facing relegation from Western Counties West.
The Sandy Park side, who sit bottom of the league, lost 30-17 away at Sidmouth. They are now 12 points away from safety with just three game to go.
Devonport Services did not do them any favours by losing 20-19 at fellow strugglers Torquay Athletic.
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