are u using CS pollen or just sexed out some regs?..when i sex out some regs an know what ones are gerls an males i sometimes remove some the male tops an let the lower parts grow so the females can keep gettin bigger b4 ya pollinate em so ya have more hairz...i ussally dust the tops first, but sometimes dust some those lower popcorn budz too..is all in how far along the gerl plants are and how many seeds ya want...like pipes sed ya need 4 to 6 weeks for seeds to develope...CS pollen ya can dust the females the same way...