Aerifying larger lawns requires a power-driven core aerator or aerifier, which can be rented at lawn and garden supply centers. The working parts of these machines are spoon-shaped tines or hollow tubes. As the tubes are driven into the lawn, cores of soil are removed from the ground and strewn across the lawn.
Nutrients with the Highest Energy Density. Fat provides more calories than any other nutrient. The macronutrients -- fat, protein and carbohydrates -- are high in energy density, which means that they have 4 or more calories per gram. The other essential nutrients -- water, vitamins and minerals -- have no calories, so they provide no energy.
Carbohydrates and protein provide 4 calories of energy per gram while fat yields 9 calories per gram. Carbohydrates are broken down into glucose and absorbed into the bloodstream. Fat is a major source of stored energy and is held as a reserve in the body until we need it. Fat is the preferred source of energy for the heart. Protein is broken down slowly and is a longer-lasting form of energy.