Answer: Unless your lawn in fairly new, it is probably a mixture of grasses. It typically takes 3-5 years for a single grass variety (such as Kentucy Bluegrass) to be invaded by other grasses in the area. You can try digging up a sample and taking it to a local nursery or garden center, or you can visit this website: http://www.american-lawns.com/grasses/grasses.html
and look at the photos and read the characteristics of each grass type listed.
Hope this helps!
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