The home side tormented the visitors’ bowling attack, posting 313-6 from their 55 overs.
Nick Kay top-scored with 72 from 94 balls, including eight fours, while Charlie Elliott was unbeaten on 62 from 43, a hard-hitting knock that included six fours and a six.
Ryan McKendry had earlier struck a powerful 47 from 40 balls, which saw him strike seven fours and a six, while Richard Love hit 36 from just 27 balls.
Skipper Andy Simpson’s 2-74 from 13 overs was the pick of a beleaguered Scarborough attack.
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In reply, Harland held the innings together as stands of 66 for the second wicket with Carl Joyce, 24, and 69 for the third wicket with Chris Grey, 26, steered the visitors to a steady 180-4.
But chasing such a large target took its toll as wickets soon began to fall quickly to the accurate bowling of Daniel Woods, 3-53, and, Tom Pringle, 4-46, the visitors slipping from 180-3 to 210 all out from 46 overs.
Harland was last man out just an agonising four runs away from a richly-deserved century.