QUESTION: Now that it's started raining and the lawn is turning green, we are wondering if there is anything we can do to prevent the moss from growing this winter. Our neighbor told us that applying lime to our lawn would help prevent moss. If that's true, how much should we apply?
ANSWER: Applying lime to the lawn now is a very good idea since winter rains will dissolve the lime and carry it into the rootzone of the grass. Unfortunately, it will do very little if anything to prevent moss from growing during the winter. Lime reduces soil acidity, supplies calcium which is an essential plant nutrient, and improves soil structure over an extended period of year.
Maintaining a regular fertilizer schedule which calls for applications in early September and late November will help to reduce the amount of moss.
Although there are no products on the market, which will prevent moss invasion, maintaining turfgrass vigor will help reduce the overall amount of moss.
WSU turfgrass researchers recommend using a complete fertilizer with a 3-1-2 ratio (N-P-K) on established lawns to supplement any lacking phosphorus and potassium. Often solds as 15-5-10 or 12-4-8, the fertilizer should be applied at a rate, which is equal to approximately one pound of nitrogen per 1000 square feet of turf. If you are using 15-5-10, for example, you would need to apply approximately 6.5 pounds of actual fertilizer product per 1000 square feet in order to get one pound of actual nitrogen. Using a fertilizer with at least 50 percent of it in a slow release form gives the best return when it comes to turfgrass vigor.
QUESTION: Now that the weather has turned cooler, we are being invaded by flies. On sunny days, the outside wall of our house is virtually covered with flies. How do we get rid of them?
ANSWER: Based on your description, the flies you are seeing are commonly referred to as "Cluster flies". As the days shorten and the weather cools, cluster flies gather on sunny sides of structures (usually the south walls, but also east and west walls) and then enter them to over winter. Cluster flies get their common name from their gregarious behavior of forming compact groups of hibernating individuals. The larvae are parasites of earthworms and are found where their hosts thrive (usually areas of wee-drained, silt-loam soils with grass cover and a lot of trees). When their environment warms whether from a homeowner turning on the furnace in the fall or from sun beating on an outside wall in the spring, the flies become active and seek light. In this manner, they are very similar to ladybird beetles, which incidentally will also soon be appearing on house walls.
Cluster flies enter houses through window frame openings, loose-fitting wall switches, outlets, ceiling fixtures, and cracks around windowsills, baseboards, and window and door frames. They then fly to windows and lighting fixtures where they may accumulate in large numbers. This activity is unsightly and annoying and the crushed bodies, heavy with fat reserves for hibernation, stain upholstery, carpets and wood surfaces.
The most appropriate control at this time of year is to apply residual perimeter sprays near potential entry points along exterior walls and overhangs to kill flies landing on the building. Pay special attention to areas beneath eaves and around windows, doors and attic vents, particularly on the structures south sides. Aerosol sprays are recommended for inaccessible areas, but if infestations are heavy, piles of dead flies can cause a secondary infestation of beetles, rodents, and other pests that feed on dead flies.
For temporary relief indoors, remove adult flies with a vacuum cleaner, or use space sprays, sticky traps or insect light traps in infested rooms.