Mulberry, White (fruitless)

The white mulberry, is a short-lived, fast-growing, small to medium sized mulberry tree, which grows to 10–20 m tall. The species is native to northern China, and is widely cultivated and naturalized in the US.
The species is now extensively planted and widely naturalized throughout the warm temperate world. More recently, it has become widely naturalized in urban areas of eastern North America, where it hybridizes readily with a locally native red mulberry (Morus rubra). There is now serious concern for the long-term genetic viability of red mulberry because of extensive hybridization in some areas. As a result, it is listed as an invasive plant in parts of North America.

On young, vigorous shoots, the LEAVES may be up to 30 cm long, and deeply and intricately lobed, with the lobes rounded. On older trees, the leaves are generally 5–15 cm long, unlobed, cordate at the base and rounded to acuminate at the tip, and serrated on the margins. The leaves are usually deciduous in winter, but trees grown in tropical regions can be evergreen
The simple, alternate, toothed leaves of Morus alba are extremely variable in shape, ranging from unlobed to heavily lobed, even on the same branch. Regardless of the degree of lobing, the leaves always have three strong veins from the base (one on either side of the mid-vein) and the sap is milky colored rather than clear.

The FLOWERS are single-sex catkins, with catkins of both sexes being present on each tree; male catkins are 2–3.5 cm long, and female catkins 1–2 cm long. The fruit is 1–2.5 cm long; in the species in the wild it is deep purple, but in many cultivated plants it varies from white to pink; it is sweet but bland, unlike the more intense flavor of the red mulberry and black mulberry.

The WOOD is prone to disease and termite invasion so the trees seldom reach maturity if they are not constantly cared for. The fruitless varieties are commonly used for landscape purposes for their fast growth and good shade tree properties.
The seeds are widely dispersed by birds, which eat the fruit and excrete the seeds, therefore the trees are found along bird migration paths, near habitat cover and near water. All WILDLIFE find the fruit particularly delicious so seed dispersal is all but guaranteed.

It is also notable for the rapid release of its pollen, which is launched at over half the speed of sound. The white mulberry is scientifically notable for the rapid plant movement involved in pollen release from its catkins. The stamens act as catapults, releasing stored elastic energy in just 25 µs. The resulting movement is approximately 350 miles per hour (560 km/h), over half the speed of sound, making it the fastest known movement in the plant kingdom.
The tree components have several pharmaceutical and medicinal uses.