The shoot system is generally used to refer to the above-ground plant parts, although some plants have parts of their shoot system underground. For example, a rhizome (PO:0004542), bulb (PO:0025356), a corm (PO:0025355) or a subterranean tuber (PO:0004547), as in Solanum tuberosum (potato) or yam, are all part of the shoot system.

A collective plant organ structure (PO:0025007) that produces shoot-borne portions of meristem tissue (PO:0009013) and the plant structures (PO:0009011) that arise from them.