The common holly tree conjures up images of Christmas, with the holly reef outside many homes over the Christmas period.
The tradition which is thought to go back to roman times from the festival of saturnalia. Today the prickly green leaves are on cards, garlands and wreaths everywhere that celebrate Christmas.
We find Holly in the undergrowth of forests from western Asia and across most of Asia. It prefers moist shady environments so can be often found oak and beech forests, but also on shady slopes, cliffs and mountain gorges.
On the west coast of America the common holly has proved very evasive, spreading quickly in native forest habitats from California to British Columbia. So much so that Washington state has placed it on the Noxious Weed Control monitor list and in Portland it has been set as a Class C invasive plant.
What else is there to know about the Common Holly
Drupe (Stone fruit)
Typically 2-3m 6.6-9.8ft - but anywhere between 10-25m (33-82ft)
Usually 100 years but rare examples of up to 500 years!
What else is it known as?
The common Holly often to referred to as just Holly is also known as English Holly, European Holly and even occasionally as Christmas Holly
What is the size of the tree?
Holly can range in size depending on its environment, it can remain as a shrub or can grow to exceed 10m in height. Typically, it will be found 2-3m (6-9ft) tall and broad. Often growing with a straight trunk and a pyramidal crown starting from the base at ground level. The common holly is a relatively slow grower.
It can live to an age of 500 years, but rarely reaches any older than 100 years in most environments.
What are the fruits or seeds?
The fruit is known as a drupe (stone fruit) which only appears on female trees. It is the famous bright red or occasionally a bright yellow and is 6-10mm in diameter. The fruits mature in Autumn around October and November, but are very bitter due to containing a substance called ilicin. As a result, animals will rarely eat them until several frosts have made them more soft and palatable.
Moreover, each fruit contains 3 to 4 seeds. The seeds do not germinate until the second or third spring.
Common Holly is dioecious, meaning that there are separate female and male trees. There is no way to determine the sex until the trees flower, which can be anywhere between 4 and 12 years of age. The flowers bloom, depending on the climate, between early spring and the beginning of summer.
The male tree produces flowers that are yellowish and appear in axillary groups.
The female Common Holly produces small white or slightly pink flowers that are isolated or in groups of three. The flower has four petals and four sepals partially fused at the base.
For the female tree to be fertilised, the male tree needs to be fairly close by, often pollinated by bees.
What do the leaves look like?
Typically, the leaves are 5 – 9 cm long and 2-6 cm wide. They are evergreen with a leaf lasting for up to 5 years. The leaves are leathery and shiny with the top surface being a dark green and underneath a lighter green.
On the lower branches of a mature tree or on a young tree you will find leaves that have 3 – 5 sharp points on each side, pointing alternatively upward and downward.
On the upper branches of a mature tree, the leaves will lack the points.
What does the bark look like?
Young trees have a green stem which is used for photosynthesis. Once the tree gets older, the bark turns silvery or dark grey that is thin and smooth.
The wood is hard, white and dense, so it has been used extensively in the past for carving. It burns brightly even when freshly cut down, moreover the green foliage is flammable.