I have a fir tree in my garden that seems to have LOADS of ticks in it. My adult dogs don't go near it so never get them but I have a litter of puppies at the moment that love to run through it playing hide and seek etc.

I frontlined them at weekend and have noticed that they're not getting as many but I'm still finding a few. I really don't want to spoil their fun by blocking the tree off, I just wondered if there was some sort of product I could treat the tree / garden with to get rid of them?

Apparently you can buy garden sprays to kill ticks. It's quite a common problem in America it seems so most google enquiries link to American products.  I couldn't find many UK links but you might have more luck if you research specific chemical ingredients see Permethrin.

Try ringing your vets too - they might be able to recommend or supply something

Good luck - I hate these little blighters but luckily we've only had one so far this year :)