Asphalt is a more flexible and stickier material than concrete and that becomes quite evident as you are cutting it, the binder that has been holding the aggregate together for so many years’ starts to warm up again with all that heat and friction.
Cutting asphalt can be done with any number of saws. For thin lifts of materials (1-4″) in small quantities, a cut-off saw with an abrasive or diamond tipped blade will typically do fine.
For thicker asphalt such as roads or heavy duty parking lots, a walk behind gas powered saw will be much quicker, efficient, and more economical. There are also commercial walk behind electric saws that can cut through asphalt for application where exhaust fumes and pollution is a concern. The thicker the asphalt you are cutting, the longer it takes to cut and the more it will cost.