Arsonists set fire to some grassland off Blythe Road, Maltby, at 7.10pm last night.
A shed was set alight in an allotment at Shaw Lane in Barnsley at 7.15pm.
Cudworth firefighters spent over an hour tackling the flames.
A crew from Birley Moor Fire Station was called out to deal with the incident.
A blaze ripped through a corn field off Doncaster Road, Stainforth, at 8pm.
Doncaster Central firefighters spent nearly 90 minutes tackling the blaze.
A crew from Cudworth Fire Station spent 30 minutes at the scene.