Further to Roy V Hilliard's letter (September 7) about dog fouling, I wonder if anyone could enlighten me?

I would like to know why a seemingly conscientious dog owner would pick up their dog's mess in a plastic bag and then throw it on the ground or, for some bizarre

reason, tie it to a branch.

As a dog owner myself, I find this behaviour odd. A biodegradable substance, although unsightly, is wrapped in a non-biodegradable material, then left not to rot in strange places.

This has been puzzling me for some time, so if there is a mysterious reason, I would love to know.

I would like to add that I manage to find a bin - usually helpfully marked with a picture of a dog.

-Ali Hawes, Brighton