I use a product called Malation Plus, the "plus" being Sevin.

Sevin in known to cause an upset stomach if you drink some, which most sane people don't do.

Malathion is less toxic than table salt, so the combination in Malathion Plus is quite benign, but effective on almost every yard pest including fleas, ants, and probably ticks.

The yard clearing (not just clean up) is more important with ticks than you might think.