PURPOSE:To leave watching of seeding situation to the care of an electric means and to promote unmanned operation, by taking a photograph of seeded soil surface of bed, analyzing the state of seed distribution from photographed information in seeding and analyzing the amount of seed fed by shade of color in dense sowing. CONSTITUTION:A seeding plant to produce mat-shaped seedling consists of a feeding part A for seedling raising boxes, a seedling treating part B and a device C for piling the seedling raising boxes in series. A color video camera CA as an image pick up device is set between a seeding device 8 and a soil covering device 9. The camera is connected to an image treating device 18 which quantizes image information, analyzes seeding condition and judges whether seeding is proper or not. The image treating device 18 is equipped with a means which converts an image to a binary dyestuff image corresponding to color of seed rice and judges whether the seeding distribution is proper or not and a means which obtains a seeding amount as a value of shade of color and judges whether the seeding amount is a proper quantity or not.
