Why is it a problem? There are lots of other animals busily crapping on your land every day, birds, hedgehogs, squirrels etc. What's the particular problem with cats? They generally bury it so it will degrade into the soil. They are all welcome to a dump at my place!
Jerry
Hifi: IPL transmission line floorstanding speakers, Squeezebox Touch, Denafrips Ares 11 DAC, DCB1 Pre-amplifier, Croft Series 7 power amp.
Custom Hifi cables HA10SE headphone amplifier and Hifiman HE-400 headphones.
AV system: LG 55B7, Denon AVR -x2300w receiver, Quad 12L (front) 11c Centre and 11L rear . Velodyne DD15 subwoofer.