Question
Hi Rick. We live in London, Ontario, Canada.We've lived at this home for 14 years,in all that time I've always had a nice looking green lawn.However the last 2 years the lawn has started to show dead spots in none traveled areas and under a birchbark tree.We don't have bugs.I was thinking maybe just try new top-soil and seed.What do you think? Thankyou.
                       Regards.
                        Harry.

Answer
i'm in southern NJ. lawn problems are generaly similar across the country,  but do vary from area to area. it does depend on weather conditions. its been a wet winter and spring(for that matter the last year has been wetter than normal) here. your problem could be caused by fungal problems. 1st visit a local garden center/nursery to see what they recommend for your area. take a sample of the damaged area(grass pieces) in a plastic sealed bag w/you. you could also take pictures of the area w/you. fungus will be present on them if that is the problem. let them try to diagnose your problem.
here are some general thoughts on how to correct dead areas in lawns.

normally 3 applications of lawn fertilizer w/some weed controls per year is enough to keep your lawn nice & thick. lime 2x's per year.
in the spring start by aerating(rent an aerator) the areas. then apply turf lime(50 lbs/1000 Sq Ft). buy some scotts turf builder lawn fertilizer(no weed controls included) and fertilize as per directed by the label on the bag. you can topdress problem areas w/composted material, humus, etc. seed w/the appropriate mixture for your area(shade mix). keep the area moist until germination starts. back off on watering as the weather gets cooler. always water before 2PM and not on rainy days.
in early spring(march-april when daffodils are in bloom) lime again and apply scotts +halts TB pre-emergent fertilizer. follow the directions on the bags for good results. this will prevent most narrow-leaf weeds from sprouting.
in late spring apply scotts +2 post-emergent TB fertilizer as per directions. wet the lawn lightly just prior to the application to aid the weed control in sticking to the weed foliage(dandelions, clover, chickweed, & other broadleaf weeds). no water or irrigation for 24-48 hrs. after that, if it does not rain, irrigate the area for 15 minutes.
in the fall aerate(rent an aerator) the areas. then apply turf lime(50 lbs/1000 Sq Ft). buy some scotts turf builder lawn fertilizer(no weed controls included) and fertilize as per directed by the label on the bag. seed w/the appropriate mixture for your area(shade mix). keep the area moist until germination starts. back off on watering as the weather gets cooler. always water before 2PM and not on rainy days.
you may need to remove the bottom branches(back to the trunk) of any shade trees on the property to allow more lite and air circulation into the areas. consult a pruning book prior to pruning. this will make it harder for fungi to live.
check w/your garden center/nursery as other problems arise.
buy products from them & they should be glad to help you.
good luck
rick
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