Police discovered a Pine Island cornfield Tuesday that doubled as a cover for a marijuana crop with a street value of $10,000.Police were tipped off when a farm worker spotted the plants and notified police of his suspicions. The marijuana plants were nearly 10-feet high. Local farmers say marijuana is a crop that?s easy to find at harvest time, but one they can?t really prevent. They say the plants are dark, grow fast and are easily disguised.Police ripped the plants out and took them in as evidence.