A collection unit (1) for the collection of loose material, such as foliage and/or grass, scattered on a ground plane (T). The collection unit (1) comprises a collection compartment (2) and collecting means (3) suitable to collect the material from the ground plane (T) and convey it towards the collection compartment (2). Additionally, the group (1) comprises compaction means (4) suitable to receive the material collected by the collecting means (3), in turn conveying it into the compartment (2), wherein said compaction means (4) comprise a rotating member ( 40) that, by rotating, is suitable to crush the material collected and to convey it into the compartment (2) compacted.
