Ticks are parasites of warm blooded animals and have a complex life cycle spending a portion of it on an animal, sucking blood from the host, and another portion in the environment going through developmental stages. The tick does not feed on the grasses, but climbs up the leaf blades in order to get on a new host. Height of the grass probably makes more difference than the species in regards to infestation. Another factor is the availability of hosts, eg rodents, cats, dogs, and deer in the area.
Here are two links to help you learn more about tick and how to control them.
gardenweb.com
