6e7fe60a_Management_in_the_Home_Orchard__Uses
[Insecticide] Pyrethrin [Class] Botanical [Uses] 
This botanical insecticide has rapid knockdown activity against many pests, but insects often recover. Piperonyl butoxide (PBO) is often mixed with pyrethrin to act as a synergist. It has very short residual activity, which limits its effectiveness.
The North Carolina Plant Disease and Insect Clinic | Disease and Insect Management in the Home Orchard
Uses