Question
We recently moved into a 7 year old house in Portland, OR, and have small, 6 - 10" dia brown patches in the front lawn.  The brown patches of grass have since died and appear to be spreading throughout the yard.  75% of the lawn looks very healthy and green, however 25% (and growing by the week) has brown dead patches of grass.  Can you suggest what is causing this and secondly, what I can do to prevent it from happening?

Answer
sounds like a grub problem. it could also be a mold or fungus problem.  i'm in southern NJ. it depends on your weather for this time of the year. you can start by taking a sample of the effected area and putting it in a clear plastic bag and sealing it. visit a local garden center/nursery and ask them to advise you. see what they recommend for your area. buy products from them & they should be glad to help you plan your solution.
it may be too late in your area(it is too late in NJ) to apply a grubacide. you may have to wait until next spring(late). if a fungus or mold problem exist they may recommend a fungicide you can apply.
always water before 2PM and not on rainy days to prevent turf fungal problems.

check w/your garden center/nursery for good local advice.

good luck
rick
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