The hosts went ahead through Luke Ashton’s try, with Kevin Boland converting.
Dees then stretched their advantage as Toby Mead crossed, while it was 17-0 at half time courtesy of Christopher Chandler dotting down.
After the break, Max Thorne went over, before Mead had his second of the afternoon, courtesy of a brilliant individual run, Boland adding the extras.
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Thorne doubled up too, touching down, while Aaron White completed the scoring late on as Dees were easy winners.