Holly is in the genus Ilex, a member of the family Aquifoliaceae and consists of 400 to 600 species that include evergreen and deciduous trees, shrubs, and climbers. Shakespeare’s holly is probably European holly, Ilex aquifolium, a popular garden plant then as now. It is an evergreen tree growing to 30-80 feet tall with shiny dark green leathery leaves that are oval in shape and about 2-5 inches long. The young leaves and those on the lower branches bear three to five sharp spines on each side, alternately pointing upward and downward. The plants bear small white male and female flowers on different trees in the spring that give way to red or yellow berries in the fall.
Lord Amiens in As You Like It (act ii, sc 7, 180) sings
Heigh-ho, sing heigh-ho, unto the green holly.
Most friendship is feigning, most loving mere folly.
Then heigh-ho, the holly.
European holly goes back to ancient times when it was made into wreaths and worn by druids on their heads. In Christian times the tree has been traditionally associated with Christmas decoration of houses and in the Middle Ages was associated with ivy in Christmas carols. The sixteenth century herbalist, Gerard, writes that holly was plentiful in all countries and that it was known in Latin as Agrifolium, in French, Hous and Housson, and in English Holly, Hulver, and Holme.