Fig. 11.1-4. Transverse section of Indian-pipe (Monotropa). Indian-pipe is a parasitic plant that spends most of its life underground, drawing nutrients from the roots of a host plant. The only stem that it makes is this one that pushes up through the soil and displays flowers in a position above ground where they are visible to pollinators. The stem is extremely ephemeral (that it, it lasts only briefly), dying as soon as the flowers have matured into fruits and released their seeds. Although it must be a vertical shoot, the strength that holds it upright is supplied by the surrounding soil, not by either collenchyma or sclerenchyma. This stem is very lightly constructed, consisting almost entirely of parenchyma. There is not even much vascular tissue – the flowers are almost completely formed by the time the stem begins its upward push, and the vascular tissues really have little function except to supply water and nutrients as the small fruits and seeds form.