Killing moss on Tarmac

Forgive me for asking, but I wonder why you feel the need to kill moss on your paths. If there’s an ugly, green, slimy algae developing it makes sense to want to clean it up, especially if it becomes slippery and dangerous in winter. But if a variety of mosses are beginning to colonise your tarmac paths, is that not something to enjoy?
One of the world’s most famous gardens, the 600 year-old Saiho-ji (Koke-dera) Zen Garden in Kyoto, Japan, accommodates 120 species of moss and yet, when the garden was first laid out, the moss arrived by accident and was welcomed as a heaven-sent blessing.
Moss, though, is not everyone’s cup of tea and if you’re determined to get rid of it, I’m afraid there is no herbicide likely to have a lasting effect. Instead, invest in a pressure washer – the cheapest are available for around £50 – and give your paths the ‘once-over’.