Look closely at living blades of grass pulled from the outer edge of the discolored area. Up to 40 aphids per grass blade is common. Vigorous, healthy turfgrass is better able to withstand aphid feeding than is stunted, stressed or unfertilized turf. Therefore, a decision to spray is not based solely on the presence of aphids. If orange discoloration is prominent this early in the season I would suggest treating.
Several insecticides are available for spraying greenbugs.
I suggest homeowners use insecticidal soap. This treatment is not toxic to people, pets and wildlife, and preserves lady beetles and other predators that may be in the area. Apply commercial insecticidal soaps according to label directions or substitute liquid dishwashing detergents by mixing 5 tablespoons of detergent per gallon of water. Soap sprays must be thoroughly applied to be effective. Spot treat only the infested area and a small buffer beyond.