A stall strip (24) disposed within and aligned with a stagnation zone (22) in incident wind (1W) on a pressure side (PS) of a wind turbine blade airfoil (20) over at least a portion (39) of a span of the blade. The stagnation zone occurs along a spanwise line or curve at a nominal angle of attack (.alpha.) during an operating condition such as 5-10% below maximum power. The stall strip may be shaped to create and support a bubble (26) of recirculating airflow on an aft side of the stall strip that maintains laminar pressure side flow at angles of attack below the nominal angle of attack until a predetermined negative angle of attack (36) or negative lift coefficient (38) is reached, and then to cause separation (27) of the airflow on the pressure side of the blade, reducing negative lift (34) on the blade.
STATEMENT REGARDING FEDERALLY SPONSORED DEVELOPMENT
 Development for this invention was supported in part by United States Department of Energy contract award number DE-EE0005493. Accordingly, the United States Government may have certain rights in this invention.