Prior to plant emergence, a designated sampling area should be marked out using flags. Sample collection must be done in this designated area throughout the sampling period. The samples collected within the sampling area are meant to give a representation of the nutrient content of the crops in the entire field. To avoid potential damage to the sampling area, we recommend marking out an area that is away from sprayer tracks, as the plants damaged by the sprayer tires are unfit for sampling.
Furthermore, it is best practice to select an area near an access road to minimize foot traffic within the fields. The predetermined plot can vary in size. A standard plot is large enough to sustain 10 weekly samples (30‐40 plants) without having the same plant sampled twice. As shown in picture, a subplot is 4‐ 6 rows wide by 5‐6m deep. We recommend using a 30” tall orange colored vinyl flag (as shown in picture below).