Glen, you're right that is not a job for the Elky. You might be surprised at delivery prices if the landscape supply isn't 100 miles away.
In typical landscape jargon you need 1.5 yds. which is 3 scoops on a typical tractor loader. Yeah, lightweight soil, 3 (actual) scoops and an 8' bed would be crown full.
One cubic yard (2 scoops) will weigh about 1.5 tons (3000 lbs.). Soils typically weigh a little less, approximately 1000-1200 pounds per scoop. Mulches weigh even less, about 400-500 lbs.
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