The vortices from larger aircraft pose problems to encountering aircraft. The wake of these aircraft can impose rolling moments exceeding the roll-control authority of the encountering aircraft. Also, the turbulence generated within the vortices can damage aircraft components and equipment if encountered at close range. For this reason, a pilot must envision the location of the vortex wake and adjust the flightpath accordingly.
AIM 4-6-7 Guidance on Wake Turbulence
AIM 7-3 Wake Turbulence
PHAK Ch-14 (26) Wake Turbulence
Pilot and Controller Guide to Wake Turbulence
2.8 Wake Turbulence Recommended Visual Avoidance Procedures
AC 90-23G Aircraft Wake Turbulence
Private Pilot ACS Page 17 Task F. Before Takeoff Check