Looking carefully at the picture, it seems the Jutsu vaporises rather than cuts. Witness the cloud, http://www.onemanga.com/Naruto/418/10/
and lack of fallen stems.
I am not perfect and I defy you to prove otherwise
Growing Old Gracefully is an Oxymoron ... Mostly Moron !
Paulbee your looking at the wrong chapter the newest chapter shows fallen stems to the right hand side of the initial cut tree.
Also I dont see why this cant be the technique naruto and jiraiya where talking about, so "we assume" its been fused with wind nature energy, what if originally it was a shape manipulation alteration of the rasengan, reducing it to a flat surface rather then a spherical ball, which only worked when naruto was in kyubbi mode, and failed when he was normal naruto as the disc dissipated after leaving naruto's grip, therefore it was naruto's idea following kakashi's training to infuse it with wind nature chakra (while training at night without Yamoto or kakashi) once he realised this wouldnt work continued with the rasen shuriken and only now has returned to perfecting it following learning sage mode for control
Jiraiya could of known naruto's element just with the chakra paper. He showed naruto's rasengan and he probably wanted to teach him further technique and/or combination to do with rasengan. Would be stupid if he took 3year learned a single trick which he learned in a week.
Btw Asuma's trick for wind element, make it thinner and sharper, seeing how the cut is nicely cut, he has it perfectly.
naruto kun has imrpoved his abilities
now he can kick sasuke's ass