On engines with belt-driven cooling fans, a fan clutch is often used to save energy and reduce noise. The fan clutch disengages slows or disengages the engine's cooling fan when extra cooling isn't needed. The fan pulls air through the radiator and air conditioning condenser when the vehicle isn't moving fast enough to provide adequate airflow for cooling.
St Augustine grass will go dormant when the soil temperatures fall below 55 degrees. If the soil remains warmer than 60 degrees all year, the grass will stay green. It will, however, slow in growth as the soil drops in temperature. Disadvantages of St Augustine grass. One of the disadvantages of St Augustine grass is its poor wear tolerance.
Cool season grass requires a minimum range of 45 - 55 degrees. Warm season grass requires a minimum 55- 65 degrees. Note that soil temperatures are usually cooler than air temperature. In addition to the density of the ground that is slower to warm up, moisture evaporating from the surface has a cooling effect.eed germination is simply the growth process that occurs when the seed absorbs sufficient moisture to start sprouting. This is regulated by soil temperature according to the variety of grass.