Vascular plants, such as squash and pumpkins, contain a food-conducting tissue termed phloem. The phloem is mainly composed of sieve tubes, sieve plates, companion cells, phloem fibers, and parenchyma tissue.

The digital image above illustrates sieve plates in cucurbita stained with a quadruple stain consisting of safranin O, fast green, cresyl violet, and orange R.