Arsonists set fire to two straw stacks on Tuesday night, August 12.
Incident 429 relates to a stack on fire off the A158 Lincoln Road, Goltho, between Lincoln and Wragby.
This was reported at 8.43pm and was dealt with by the Fire and Rescue Service. No-one was injured but a substantial quantity of straw was destroyed.
Incident 454 was reported later at around 9:18pm. A straw stack was reported as ablaze off the B1241 Stow Road, Willingham by Stow near Gainsborough.
Again the Fire and Rescue Service attended and a large amount of straw was destroyed.
Officers are investigating any possible link between the two offences.
Investigating officers are asking for any witnesses who saw anything suspicious in either area or who as any information that may lead us to the persons responsible to call the non-emergency 101 number and quote the incident numbers.