Granted, your wish causes pine trees all over the world to stop releasing pollen. Immediately 1/10 of the world's population mysteriously disappears into thin air. With no reproduction, the pines soon die out and become extinct from excessive logging. The death of the forests cause the collapse of entire ecosystems. Plant and animal life disappears across the face of the earth, and great war follows over the control of natural resources. Famine and plague spread in the aftermath, many suffer, few survive. The remaining survivors wage further war across the now barren lanscape. Massive earthquakes decimate every inch of terrestrial land while fire and ice rain from the skies in sheets. The dead crawl from their graves and slaughter 1/3 of humanity. After this plague passes, many will seek death though none will find it. Painful open soars much like lepersy that grow 6 inches in diameter before bursting torment all of humanity. In the maelstrom, a giant meteor the size of New York falls into the pacific ocean, destroying the delicate currents which keep it alive. This mixed with the water turning to acid kills all marine life in the world and brings about a new ice age. Volcanic ash from the meteor causes a blanket of soot to cover the earth, allowing no visible light to reach its surface causing complete darkness. The ozone layer is destroyed, intensifying ultraviolet light. Anyone who ventures out from under shelter into the frozen pitch black abyss is terrably sun burnt. Because you sold your soul for your simple wish of a pollen free world, you may not repent your sins. Seven years after your wish, the armys of the lord rain down from heaven and smite you. You spend the next 1000 years in hades regretting your wish before spending the rest of eternity cast into the lake of fire which is hell.
I wish the interview for my new job as IMAX operator goes well.