<P> The stolons are easily recognized when potato plants are grown from seeds . As the plants grow, stolons are produced around the soil surface from the nodes . The tubers form close to the soil surface and sometimes even on top of the ground . When potatoes are cultivated, the tubers are cut into pieces and planted much deeper into the soil . Planting the pieces deeper creates more area for the plants to generate the tubers and their size increases . The pieces sprout shoots that grow to the surface . These shoots are rhizome - like and generate short stolons from the nodes while in the ground . When the shoots reach the soil surface, they produce roots and shoots that grow into the green plant . </P> <P> A tuberous root or storage root, is a modified lateral root, enlarged to function as a storage organ . The enlarged area of the root - tuber, or storage root, can be produced at the end or middle of a root or involve the entire root . It is thus different in origin but similar in function and appearance to a stem tuber . Examples of plants with notable tuberous roots include the sweet potato, cassava, and dahlia . </P> <P> Root tubers are perennating organs, thickened roots that store nutrients over periods when the plant cannot actively grow, thus permitting survival from one year to the next . The massive enlargement of secondary roots typically represented by Sweet Potato (Ipomoea batatas), have the internal and external cell and tissue structures of a normal root, they produce adventitious roots and stems which again produce adventitious roots . </P> <P> In root - tubers, there are no nodes and internodes or reduced leaves . Root tubers have one end called the proximal end, which is the end that was attached to the old plant; this end has crown tissue that produces buds which grow into new stems and foliage . The other end of the root tuber is called the distal end, and it normally produces unmodified roots . In stem tubers the order is reversed, with the distal end producing stems . Tuberous roots are biennial in duration: the first year the plant produces root - tubers, and at the end of the growing season, the plant shoots often die, leaving the newly generated tubers . The next growing season, the root - tubers produce new shoots . As the shoots of the new plant grow, the stored reserves of the root - tuber are consumed in the production of new roots, stems, and reproductive organs; any remaining root tissue dies concurrently to the plant's regeneration of next generation of root - tubers . </P>

Four plants that store food in their stems