Holly berries are an important source of food for some birds.

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Characteristics of Holly

Holly (Ilux Aquifolium) is a shrub or tree found primarily in North America, Europe and Asia. With hundreds of species of the plant ranging from short shrubs (two meters high) to tall trees (up to forty meters high), it's known primarily for its bright crimson berries and prickly green leaves.

Hollies can be evergreen, meaning the plant's glossy leaves are on the tree year-round, or deciduous, meaning the leaves fall off seasonally. Most hollies are evergreens that can thrive in the sunlight or the shade and benefit from well-drained soil. The leaves, characterized by a waxy texture and serrated edges, are dioecious, with male and female reproductive structures found on separate plants. Both male (staminate) and female (pistillate) hollies bloom in May or June, yielding white flowers. But only the females can produce berries. In order for this production to occur, a male plant must be near a female plant for the process of pollination to take place. Insects, like bees, help cross-pollinate female hollies, transferring pollen from the male to the female plants.

Like its holiday companion, mistletoe, a holly's berries are toxic to humans, resulting in nausea and severe stomachaches when ingested. Not so for some animals. Berries are a vital source of food for birds such as thrushes and blackbirds. Holly berries, which ripen in early winter, typically contain four seeds each. The birds that eat these seeds help scatter them for germination, the growth of new holly plants.

­Although the scarlet berries are famously prominent in homes for the holiday season, they're not the only useful part of hollies. The berries are poisonous, but the green leaves have been used in herbal remedies for centuries for various medical conditions like dizziness, fever and hypertension, though there is little medical proof of the plant's effectiveness. Holly wood is hard and compact, making it excellent for carving; it's sometimes used to make chess pieces and walking sticks. And while the berries provide nourishment for birds, a holly's bark can be used to make a sticky substance called birdlime, used for trapping birds. Birdlime, which can be made by boiling holly bark for several hours, is illegal in many countries and viewed as inhumane.

For more information on holly, mistletoe, and all things Christmas, visit the next page. ­