seed flow to one of the seed cups during selective passes a control system for the unit allows the shut off to be automatic after a selective number of passes have been completed or manual as selected by the operator the unseeded rows are used after germination for guiding a crop sprayer so that there will be no spray overlap and no gaps between the sprayer passes application_number US 49944595 A description referring to the accompanying drawings especially to fig1 there is illustrated a sprayer 10 spraying a field using a boom 12 in this instance the field has been seeded using a seeder with a 24 foot width in seeding the field one row of seed has been omitted on every four passes of the seeder this leaves marker lines 14 with no crop growth at 96 foot spacings across the field since the boom is 96 feet in length the sprayer 10 may follow the marker lines across the field and cover the complete crop with no overlap or gaps between the boom passes fig2 and 3 illustrate a seed box 16 of a conventional form with a series of seed discharge openings 18 along the bottom wall of the box below each discharge opening is a seed meter 20 with the usual flute 22 for metering the seed from the seed box and driven by a transverse drive shaft 24 this structure is conventional to shut off the seed flow to one of the seed meters a.