A system which automatically recognizes the curve direction at the end of a row of trees. The Optic-Drive system automatically deactivates the nozzle ring which has been averted from the row of trees and must not be activated at this time. Thus, it is no longer necessary for the user to have to make manual switching operations when turning into a new row of trees. The two OPD-01 optic sensors, which are attached to the front of the spraying unit on both sides, measure continuously if and when the next row of trees is embedded. The optic sensors OPD-01 are connected directly to the control unit SPG-20 by means of an additional board LEX-04. It is therefore also possible to retrofit the Optic-Drive system to the already existing control unit SPG-20 with the additional board LEX-04. The sensors and their electronics are encapsulated in a splash-proof plastic housing and are therefore ideally suited for the permanent outdoor application for agricultural use.