Question
We lost part of our lawn last year to grubs.  We have placed insecticide this year for the grubs on both our lawn and our neighbors (we share a big part of the lawn).  We are debating between sod and seed.  I heard seed is better as the roots are deeper.  We are not in a hurry for the grass to grow.  Also, do nurseries normally sell the germination blanket and is this worthwhile for seed.  We live in Chicago.  

Answer
angie
i lived in chicago in the 70's for about 1&1/2 years. i have loads of relatives out there now(brother, aunt, and many cousins). even had an aunt angie years ago). i'm in southern NJ now.
sod is best, but also 10 x's + more expensive. depth of roots is dependent on many factors(seed type/grass type, proper watering, fertilizing, leaving lawn at 2-3" thick to promote better rooting, etc.)
merion blue grass was the predominant type grass in the 70's for your area. then it developed a fungal problem and most of it died.
you need to get to a local garden center/nursery and ask them for a grass seed mixture(1-3 types of kentucky blue grass and perennial rye). anything similar to this will do. it will say what types of grass are in the bag on the seed label. tell them you want something for a sunny, sun & shade, or shady location.(it should say it on the label)depending on your situation.
scratch the surface of the ground before applying the fertilizer and seed. you may want to spread some pelletized turf lime also to sweeten the soil(raise the pH - turf grasses like around 6.5 pH.
put the fertilizer down 1st. then the lime. and lastly the lime. use a roller to push the combination(especially the seed) slightly into the ground. keep it moist 2 to 3 weeks (no dry spots) until it is ready to cut. about at 3".
tall. don't water after 4-6 PM-don't want to encourage fungi. then only water during dry spells.
seed mats are priced in between(closer to sod price). you have to decide if you want instant grass(sod), seed mat(faster seed germination), or seed(slower grass production-but definitely less expensive).  that's your decision and labor choice.
good luck
rick
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