Friend or Foe?

            In its natural habitat English Holly is a useful member of the community. Holly berries are an important food source for birds, as well an occasional snack for sheep, goats, and a number of deer species. In exchange for nutrition, animals that ingest Holly berries complete their mutualistic relationship by contributing to its reproduction and widespread distribution. As an English Holly tree grows larger, some of its branches may touch the ground and take root. As these branches become thicker and more numerous they can provide shelter for larger animals in the vicinity or even become a playhouse for small children.

            There are a number of pests  that can plague English Holly and affect its growth and reproduction. Aphids, which are small, slow-moving insects that suck the fluid from a number of plant species, can cause deformed leaves and leave the Holly plant vulnerable to viruses. The larvae of moths, beetles, and flies, often called leaf miners, can burrow into the leaves of Ilex aquifolium and create a pathway of damage through the tissues of the leaves.

            Unlike the mutualistic relationships that many plants have with fungi, English Holly experiences a number of diseases caused by the Fungi kingdom. Black Root Rot, caused by the fungus Thielaviopsis basicola, can stunt plant growth and spreads quickly by means of mycelium and wind dispersed spores. If the fungus continues to thrive the plant will slowly decline and eventually die. Phytophthora cinnamomi and Armillariella mellea both cause similar, but less common root rot diseases. These types of root rot require specific conditions to occur and seldom result in the death of the plant. A number of leaf spot diseases, also caused by fungi, occur in members of the Holly family. It is uncommon, however, to see these leaf spot diseases in English Holly.

Figure 1: An insect taking shelter on an English Holly leaf.

            As for humans, Ilex aquifolium has both uses and dangers. One of the most important things to know about this species is that the berries contain a number of toxins that are harmful to humans. The most important of these toxins is saponin, a chemical commonly used in soaps and detergents. Other toxins include phenolic, a compound used in plastics and high pressure laminates, and alkaloids, which are commonly used in anesthetics and stimulants. Human ingestion of berries can cause a variety of gastrointestinal symptoms including nausea, vomiting, abdominal pain and diarrhea. Children experience all of these symptoms as well as stupor and drowsiness.  

            Despite the unpleasant symptoms created by ingestion of Holly berries, they are many ways that the berries, as well as the leaves and the bark of the tree, can be put to good use. Although it is rarely used in modern herbalism, English Holly was once a very popular medicinal plant. Ilex aquifolium berry, although poisonous in large amounts, can be used to treat swelling due to excess fluid build-up. They may also be powdered and used as an astringent to check for bleeding. Roasted English Holly fruit was once used as a coffee substitute, but only when exercising extreme precaution.

Figure 2: Holly branch with leaves.          

            Holly leaves can be used to treat a number of ailments. They are known to have astringent, diuretic and expectorant effects. In other words holly leaves can diminish blood loss, increase urine discharge and increase the expulsion of mucus from the lungs. In some cases the leaves are used in the treatment of fevers, rheumatism, cararrh and pleurisy. Those who have suffered from jaundice have found the juice from the leaves to be an acceptable treatment as well.

            Last, but certainly not least, is the use for Holly wood. Holly wood is a hard, dense material that, when well dried and seasoned, can be used to make beautiful furniture. Although it can be difficult to work with it is highly regarded by cabinet makers because of its beautiful white look after it has been polished. As trees grow older the wood begins to turn a brownish color, but it is still used for printing blocks and engravings.

Holly and the Christmas Spirit...