Where has all the Holly gone? By Margaret Franklin
Holly has traditionally been associated with Christmas and has been used in festive decorations for centuries. The contrast between the dark, glossy, prickly leaves and the smooth bright red berries makes a colorful display. But it is becoming increasingly difficult to find holly with lots of berries growing in the wild. Strictly speaking, the red fruits of the holly are not really ‘berries’ at all. In botanical terms, this type of fruit is classified as a ‘drupe’. Cherries and olives are other examples. While we can safely eat cherries and olives, it is better not to eat the fruits of the holly, which are slightly toxic to humans. They cause vomiting and act as a laxative when ingested, but the effects are rarely fatal. However, holly fruit provides a very important food source, in winter time, for birds and other wildlife. The bright red fruits attract birds when other foods become scarce. This usually happens after the frosts have reduced their toxicity. Birds often take shelter from winter storms in holly bushes. While the birds derive nutrition and shelter from the plants, they also help to disperse the seeds, which pass through the digestive tract and are expelled, well away from the parent plant, after the fleshy part of the fruit has been digested. So it is a win-win situation. Holly belongs to the genus Ilex, which includes a great variety of trees, shrubs, and climbers. It can have evergreen or deciduous leaves and occurs all over the world, in different habitats. Species of Ilex are found from sea level to altitudes o 2,000 metres or higher. There are about 500 different species within the genus Ilex worldwide. Different species are adapted to different climates. The greatest variety of Ilex species occurs in North & South America and in Southeast Asia. Holly plants usually grow very slowly, but over time can reach a height of over 10metres.
Some holly species are rich in caffeine and are used to make herbal infusions. In South America, Yarba Mate (Ilex paraguariensis) is boiled to make an invigorating drink called Mate, or is steeped in water to make a cold drink. Another species, Ilex guayusa, is used as a stimulant. Its leaves have the highest known caffeine content of any plant. Examples of Ilex occurring in Asia include Ilex cornuta (horned holly) found in China, Ilex crenata, or Japanese Holly and Ilex dipyrena, Himalayan Holly. In North America, the evergreen winterberry, also known as the bitter gallberry, belongs to the holly family, with the botanical name Ilex glabra. In Ireland, as in the rest of Europe, only one single holly species occurs, the Ilex aquifolium. The plants have glossy dark green leaves, with very prickly serrated leaves. In Summer, they produce small, greenish white in flowers, with four petals. But the male and female flowers occur on different plants. The male flowers bear the pollen, while the female flowers contain the stigma and ovary, which develops into a fruit after pollination occurs. Both need to be growing in the same vicinity in order for pollination and fertilization to take place, allowing fruits to develop on the female plants. The problem is that when people gather wild holly to decorate their homes at Christmas time, they only pick the female plants, since these carry the beautiful red fruits. Gradually, the countryside becomes denuded of the female holly and the male plants have fewer female flowers left to pollinate. Many people have noticed that fruit-bearing holly has become scarce in recent years, which is a pity, as it is such an ancient species. In distant geological times, ancestors of our modern Ilex species became isolated from the remaining Ilex when the ancient continents of Gondwana and Laurasia broke apart. This happened about 82 million years ago, resulting in a physical separation of the holly groups. On each continent, each group of Ilex evolved along different lines, becoming adapted to different environments, to give us the variety of Ilex species that are found in the world today. Fossil records show that the genus Ilex was widespread by the end of the Cretaceous period. It survived the mass extinction event that wiped out the dinosaurs. Scientists believe that the common ancestor of most of the species found today probably appeared during the Eocene, about 50 million years ago. The Ilex genus proliferated during the Paleogene, when laurel forests covered much of the Earth. This type of temperate evergreen forest became extended during the Neogene, over 20 million years ago. But these temperate forests seem to have died out about 10,000 years ago, at the end of the Pleistocene. Between the 13th and 18th centuries, before turnips were introduced, holly was grown for use as winter fodder for cattle and sheep. Less prickly varieties of holly were obviously preferred. The leaves growing near the top of the tree have far fewer spines, making them more suitable for fodder . Many types of holly are now becoming rare. Some tropical species are threatened by habitat destruction and over-exploitation. Two species of Ilex have become extinct recently, and others are barely surviving . While our native Ilex aquifolium is not yet an endangered species, female holly plants are becoming rather scarce. So have a great Christmas, but let us not plunder too much wild holly from the countryside!
Where has all the Holly gone?
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Where has all the Holly gone?
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Margaret Franklin [Class, Semester] [Teacher Name] [Insert Date]
Where has all the Holly gone?
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