POLICE from Ipswich's tactical crime squad are trying to work out who left about 85 marijuana plants in bushland at Blackstone.
The vast collection of plants - all about 1m high - was uncovered by council workers on a council-owned site off Jones St, near the old Blackstone State School, about 2.30pm Thursday.
The plants were all being grown in black plastic pots.
Police have seized the plants.
Anyone with information that could assist investigations should contact Crime Stoppers on 1800 333 000.