Crabgrass, wiregrasses and moss all love compacted soil (Sir toppam hats
point) A good thorough plug aeration in the fall will help a great deal.
Pelletized lime at about 1000 sq ft per 40 lb bag twice a year and
pelletized gypsum (when aerating) will loosen the root bed. In PA, do you
use any sort of ice melt, because that in itself will compact the soil. It
doesn't kill the grass itself, it just compacts and of course, that does the
killing. Crabgrass germinates 3 times a year. February, around Mothers Day,
and about Aug. 10th. (in zone 7 -- check your ext agency web site for your
zone) The Feb. crop is the hardiest of all because it has wintered over and
needs to be dealt with more carefully. Usually, when Forsythia is budding
you want to get the Pre-em down then or you will miss it.Usually when the
weed or moss is around the edges, then the aeration or Pre-em is not being
done to the edge. Most peoples lawns will show this after the next crop has
died. I moved to a house where the previous owners LIKED the vile weed. I
waited for it to go brown, lit it with a match, and burned it along with the
seed and started over.. Very nice fescue now and I'm still cutting it here
in Richmond Va. in January.
Getting to the other side, do you see mole hills in your lawn? If so then
you may have grub activity and that is what is making the brown patches. Dig
a spot about the depth of a spade at the edge of the spot and see if there
are grubs in there.(you may need to do a couple of spots to find the
buggers) If so then treat accordingly with a grub killer.


"cardarch" wrote in message
oups.com...
I live in Philadelphia PA. Is it normal to have straw-colored lawn
patches on the lawn in the winter? These straw patches dont exist in
the grass Ive sown in the past 3 or 4 years. My lawn needs renewal but
I cannot dig the entire thing up. There are mossy patches around the
edges. Also low patches. I am wondering when to apply pre-emergent
weed killer and fertilizer and new seed and which new seed to use and
if I can erradicate the winter straw colored patches.