A bale forming apparatus (1) forms a round bale (B', B), wraps the bale (B), and ejects the bale. A discharge gate (11) of a casing (11, 15) is in a bale forming position while the bale (B') is formed. For wrapping the bale (B) the discharge gate (11) is pivoted into a bale wrapping position. A web detecting sensor (99) detects whether or not provided web is present on the surface of the bale (B). This web detecting sensor (99) senses a segment of the bale surface which is visible through a nip (N) between a stationary casing part ( 15) and the tailgate ( 11) being in the bale wrapping position. The wrapped bale (B) is ejected.
