Sap transport proteins. Recent evidence indicates that mobile proteins and RNA are part of the plant's long-distance communication signaling system. Evidence also exists for the directed transport and sorting of macromolecules as they pass through plasmodesmata." A large number of insects of the order Hemiptera (the half-wings), feed directly on phloem sap, and make it the primary component of their diet. Phloem sap is "nutrient-rich compared with many other plant products and generally lacking in toxins and feeding deterrents, [yet] it is consumed as the dominant or sole diet by a very restricted range of animals". This apparent paradox is explained
Woody plant certain species in family Polygonaceae. These herbs are not truly woody but have hard densely packed stem tissue. Other herbaceous plants have woody stems called a caudex, which is a thickened stem base often found in plants that grow in alpine or dry environments. Under specific conditions, woody plants may decay or may in time become petrified wood. The symbol for a woody plant, based on "Species Plantarum" by Linnaeus is , which is also the astronomical symbol for the planet Saturn. Woody plant A woody plant is a plant that produces wood as its structural tissue. Woody plants are