Question
I live in Portland Oregon...I see Scotts sumerguard advertised would you reccomend an application in my area...I have sprinklers but there are a few brown patches or areas that i do not understand...

Answer
Do not fertilize a lawn in Portland in the summer months (never). Fertilize in late spring, early fall and late fall. Not in summer.

Summerguard is not a good choice. There is no reason to apply insecticides to lawns. It kills far to many beneficial insects than it eliminates. Brown spots are common in summer and not always caused by insects. Besides, adding fertilizer to the lawn in summer should be avoided.

If you have identified the insects which could be causing the damage, you can buy spray bottles to apply directly against them (check the lable for proper product). Do not use the products that mixes fertilizer w/insecticides.

Brown spots can be caused by hot humid conditions (lawn disease), or simply by the temperatures (a lawn is a mixture of various grasses, some of which are excellent green in cool weather, but which can turn brown in hot weather). Fertilizing a stressed lawn which is going dormant in summer is not the solution.

In your area, only fertilize in late spring, early fall and late fall.

To explain why I say this, consider that when temperatures are cool, cool sesaon grass plants take the fertilizer up through the roots and convert it into plant energy for growth.  In hot weather, the grass plants can not produce energy and if fertilized, growth will come at expense of stored energy. If you fertilize primarily in fall you prompt the grass to produce and store energy for later use. If you fertilize primarily in summer you deplete the stored resources of plant energy and that can weaken the grass.

A good choice is to fertilize lightly in late spring to green up grass for the summer and then concentrate most of the fertilizer applications to fall when the grass can maximize storage of energy for next year's growth.