Hi Kathy,
A cat peeing on the bed (and other items with the owner's scent on them) can be an indication of underlying stress. Or is it possible that your kitty doesn't like the feeling of the pine pellets on his paws? Generally speaking, cats tend to prefer soft, sand-like clumping litter (though all cats are individuals, and he may be fine with his current litter). There are several variables to consider when a cats starts peeing outside its litter box.
However, the recommended first step when trying to resolve inappropriate elimination in cats is a visit to the vet to rule out a medical issue, including pain.
Cat behaviorist Pat Johnson-Bennett has a great website with lots of helpful information on cat behavior, including "litter box issues". Here's a link to an article specifically on cats peeing on the bed:
https://www.catbehaviorassociates.com/why-does-my-cat-pee-on-the-bed/
Best of luck with your kitty! I know this type of situation can be hard on both cats and cat parents.
p.s. I created a little video on this topic recently and will try to post the link later.
#PetBehaviorandTraining