Twenty-one-year-old Slade came up through the ranks at Sky Bet Championship side Burton Albion.
He went on to make six first-team appearances for the Brewers and also spent time out on loan with Redditch United and then last season with then Ferriby`s National League North rivals AFC Telford United, for whom he appeared four times.
Also penning National League forms is 19-year-old goalkeeper Jordan Douglas.
Douglas (pictured), who joined last year from Humber Premier side Reckitts, spent time out on loan with Toolstation Northern Counties East League neighbours Hall Road Rangers last season.