Grading standards are determined by the customer, depending on their intended use. Larger seedlings are needed for moist planting sites where planting competition is severe, or on sites where animal damage is serious. Shorter, stockier seedlings with a proportionally larger root system are required for harsher, drier planting sites. Often, the nursery manager negotiates these standards with the customer when the seedling order is taken. Grading standards usually consist of a range of acceptable shoot heights, a minimum acceptable caliper (stem diameter), and the length and fibrosity of the root system. Of course, the seed code for the specific seed lot is also carefully monitored during the grading process.
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