Hi welcome to Taiga Bonzai, we continue out discussion on trees and shrubs often found in bonsai starting with the letter ‘K’.

Introduction – in this section we mention species of tree and shrubs that are found in other regions of the globe. Some have found their way to the west by various means via famous botanists, Carl Linnaeus, (1707 – 1778) Alexander von Humboldt (1769-1859) and George Washington Carver. (1804- 1943) Today many species are available from horticultural establishments and on line purchasing.

Kentucky coffee – Gymnocladus dioicus family Fabaceae. A species native to north America is also used in bonsai. Its rough ash-grey bark similar to that of oak can fall or peel away from its surface leaving scarring and indentations, which adds character to the tree. Its flowers are dioecious and has fruit in the form of a hard-shelled bean in pods from 13cm to 25cm. (5 to 10 inches)

The seeds are considered poisonous as they contain the toxic alkaloid cytosine, that if consumed can cause respiratory difficulties, which can have fatal results. However, it is argued that if the seeds are roasted, the cytosine is neutralized, but for those with respiration problems it is not a risk worth taking.

Kumquat – Fortunella japonica family Rutaceae. The species has no known toxins harmful to humans and is usually grown as an ornamental plant, but is found in bonsai collections. The fruit resembles a small orange a little larger than a grape, its peel has a sweet flavour whilst the inner pulp is sour but is edible when cooked.

It is also ingested in its raw state, but those with a sensitive digestion system should refrain from doing so due to the concentration of oils (Limonene) and acids within the fruit. Which can cause diarrhoea, nausea and other abdominal complaints.

Kurrajong – Brachychiton populneus family Malvaceae, also called the ‘bottle’ tree. Is native to Australia and found in various habitats from wet coastal districts to semi-arid regions. The bell-shaped flowers range in colour from pale cream to pink with simple pointed shaped leaves.

The seeds are covered in small stiff irritating hairs, which have to be removed prior to roasting and ingesting as they contain toxins. Although these are not considered dangerous to humans they can be to domestic pets, sheep and cattle causing lameness, tremors, collapse and in some cases fatality depending on the victims disposition.

Laburnum – family Fabaceae. Is a genus of two species of trees that are Laburnum anagyroides known as the common laburnum and Laburnum alpinum the alpine laburnum. They are often found in bonsai collections due to their colourful yellow pea-like flowers. That are in pendulous leafless racemes 10–40 cm (4–15.5 in) similar to the wisteria, making them very popular trees.

However, all parts of the tree are poisonous; roots, bark, wood, leaves, flower-buds, petals and seeds as they contain the toxin cytosine a nicotinic receptor agonist that produces a biological response. Symptoms may include intense lethargy, vomiting, convulsion, coma and severe diarrhoea.

Laurel (Cherry) Prunus laurocerasus family Rosaceae. Is a shrub often used for topiary in hedging and also in bonsai as it is easily shaped. The leaves are a shiny dark green with creamy white flowers and fruit that turn black when ripe.

The whole plant is poisonous containing the toxin hydrogen cyanide, also known as prussic acid and identifiable by its strong almond-like smell and bitter taste. Symptoms can include breathlessness, weakness, spasms, convulsions, coma and respiratory failure.

Lilac – Syringa vulgaris is a genus of 12 currently recognized species of flowering woody plants in the family Oleaceae native to south eastern Europe and eastern Asia.

This particular species has been historically used in various traditional medicines in Asia for treating ailments including cough, diarrhoea, acute icteric hepatitis, vomiting, abdominal pain, and bronchitis.

Despite the medicinal attributes of the common lilac Syringa vulgaris, the Persian lilac of the Melia genus is very toxic for felines. It can cause gastrointestinal distress, muscle weakness, tremors, and seizures if ingested.

Moreover, lilac is prone to powdery mildew disease. The fungus has no direct negative effects on humans, but it can cause problems for many people who are allergic to this particular mould or suffer breathing problems.

Mistletoe – Viscum album is a hemiparasitic plant in the order Santalales. A mistletoe seed attaches itself to a tree by a structure called the haustorium and is able to germinate independently, but as it develops it penetrates the branch of its host absorbing nutrients and water.

The European mistletoe has evergreen leaves in pairs with waxy white berries in clusters of two to six, that contain the toxins polysaccharides, alkaloids, and lectins. Which can cause blurred vision, nausea, abdominal pain, diarrhoea, blood pressure changes that can be fatal.

Those taking Telmisartan a prescribe drug, which is used to treat high blood pressure (hypertension) should be aware of potential problems. Mistletoe is found in bonsai, but is uncommon as it can affect other species within a collection.

Mock orange – Philadelphus coronarius family Hydrangaceae. A species of flowering plant native to Southern Europe is a deciduous shrub. Growing to approximately 3 m tall by 2.5 m wide and often found in bonsai collections. What makes this a popular collectable species is because of its bowl-shaped double white flowers on prominent stamens, that are highly fragrant.

The ‘toothed’ dark green leaves turn to yellow in autumn adding more colour to the plant. Yet the seeds and flowers carry toxins that although considered mild, are not life threatening. However, they can cause nausea, vomiting, diarrhoea and skin rash if consumed. But much will depend on an individual’s digestive system.

Myrtle – Myrtus communis family Rosopsida. A common species found in bonsai has reddish brown bark that is apt to peel off in mature plants. The flowers usually white in colour have five petals and numerous long stamina and can be heavily scented.

The leaves are small, narrow and dark-green and filled with oil, which is visible as small dots when held against a light. This oil is slightly toxic and may cause headaches, nausea, indigestion, and may colour urine purple if consumed in large quantities.

Nandina – Nandina domestica family Berberidaceae. A common colourful species used in bonsai is not a bamboo plant as it is often referred to. It is an evergreen shrub growing to 2m (7ft) tall by 1.5 m (5ft) in width. In springtime new leaves are a bright pink, which turn a glossy green. The flowers are white and in clusters, with fruit in the form of a bright red berry.

All parts of this tree are poisonous as it contains compounds that produce hydrogen cyanide, which could be potentially fatal if ingested. Although there are those who claim the tree is non-toxic to humans, ascertaining if there is any truth to the argument is not worth the risk.

Neea – Neea buxifolia family Nyctaginaceae in the Saltwood genus. Often referred to as the flowering tropical boxwood is native to Puerto Rico. It is a rather twiggy specimen with a large diameter trunk with small long narrow oblong leaves, with new shoots appearing in dark red, flowers and red fruit.

No part of this tree should be ingested as it belongs to the Nyctaginaceae family, in which many members such as the Bougainvillaea another favourite in bonsai are poisonous. Symptoms are similar to that of poison ivy and may include, pain, itching or burning skin, blisters and dermatitis.

Nutmeg – Myristica fragrans. Although uncommon in western bonsai collections, can be found in more temperate climes. The problem with Nutmeg seed propagation is that there is no way of knowing once germination has taken place, if the plant is male or female. Because this species is dioecious and male trees are unproductive.

The common way if one desires a female fruiting tree is to take a cutting from a female plant, then either graft, patch bud or air layer, or via the ‘T’ graft method. This is carried out in late winter or early spring, using dormant scion wood.

The Nutmeg although widely use for culinary uses contains the toxin myristicin, a monoamine oxidase inhibitor and psychoactive substance. If ingested in large quantities can induce convulsions, palpitations, nausea, dehydration and generalized body pain.

In the next article of this series ‘toxicity’ we will continue with the letter ‘O’ going forward, until next time, BW, Nik.