Wednesday, January 26, 2011


Winter has officially just started but in the Maltese islands this time of the year is more like a northern spring. The countryside is all green and many plants are starting to flower. Last Sunday I saw the first blue flowers of the borage which will be there for one to enjoy throughout the rest of winter and most of spring.

Borage, which is known in Maltese as fidloqqom, is also known as starflower. It probably originated in Syria and surrounding countries but is now found throughout the Mediterranean as well as in much of Europe, North Africa, Asia Minor as well as South America.
Borage has been cultivated for a long time for culinary and medicinal uses. Nowadays it is grown mainly for the production of a health supplement known as starflower oil or borage oil.
The active substances are found in the leaves and in the flowers which contain mucilage, nitrates of calcium and potassium, etc. Thanks to its mucilage borage is a demulcent and sooths respiratory problems. It is also used as diuretic, depurative as well as to treat inflammation and itchiness. For skin conditions one should soak the flowers and leaves in the water before having a bath.
The leaves are used in salads or as a garnish while the flowers are the source of a blue colouring agent used in desserts. Different parts of the plant are used in various dishes in many parts of Europe including Germany, Spain and Greece. I once tried a recipe from the Ligurian region of Italy in which the leaves are used for the filling of ravioli and the flowers to make a very good tasting sauce.
The English name is similar to its scientific name borago. There are many explanations for the origins of this name such as borago being a corruption of corago from cor (heart) and ago (I bring) but the most likely origin is from Arabic abou-rach, “father of sweat” because when drunk as an infusion it encourages sweating as it has been known since antiquity to have an effect on the adrenal glands and by increasing the production of adrenaline it gives courage. (This article was published in The Times on 28.12.10)

The cottony scale insect

The cottony cushion scale is native to Australia. It was identified in New Zealand in 1878 but spread to every place around the world where citrus trees are cultivated. In Malta it was found in a garden at St Georges near San Giljan in 1907. Immediate action was taken to slow its spread to other parts of the Maltese islands until a system to control it biologically which was giving successful results in other countries could be used in Malta. The action taken might have slowed down its spread but did not stop this insect from reaching the central parts of Malta, including Lija, Attard and Balzan which at the time were well known for the cultivation of orange trees.
Last summer a small numbers of scale insects decided to set up home on some of my aubergine plants. I allowed them to grow so that I would be able to photograph them and follow their life cycle. This species of scale insects has an oval shape and can grow up to half a centimeter long. Mature insects attach themselves to a host plant by means of waxy secretions and remain stationary. In summer they produce a white egg sac on grooves on their back in which they deposit hundreds of red eggs. A few days ago I photographed minute nymphs coming out of the egg sac. These nymphs are the dispersal stage of the insect. They crawl from one plant to another but they are so are so light that they are often lifted up by the wind and carried to other areas to establish new populations.
The nymphs damage the host plant as they suck fluids from the veins of leaves and small twigs. As they grow they break out of their skin (exoskeleton) and move to another spot leaving behind their telltale skin and waxy secretions. When they become larger they move to larger twigs and eventually to the branches or tree trunk.
Most cottony cushion scales are hermaphrodites. They fertilise themselves and produce hermaphrodite insects. Males do exist. When a male fertilises a female both hermaphrodites and males are produced.
This insect is of interest because it was one of the first pests to be successfully controlled biologically. Between 1888 and 1889 a species of ladybird, the vedalia beetle, was imported into the United States from Australia to control this pest which was threatening California’s citrus trees. The experiment was a success and farmers in other countries started to use the beetle to control the scale insect wherever it appeared. In 1911 the vedalia beetle, which is known in Maltese as nannakola tas-salib, was imported into Malta by the Department of Agriculture to control the spread of the cottony scale insect which by that time was infesting citrus trees in most parts of Malta. (This article was published in The Times on 22.12.10)


Lantana (Lantana camara)
In Malta the lantana grows very well and although it is widely planted as an ornamental garden plant it has not become a pest as it has in many tropical and sub-tropical countries.

 It is originally native of the American tropics. Its native range includes Mexico, Colombia and Venezuela as well as in the state of Texas in the United States.

 In Malta it is commonly known both in English and Maltese as lantana but it is also known as the Spanish flag, West Indian lantana and the red or yellow sage and in some places as ham ‘n eggs or bacon and eggs. The latter two names are popular in the United States because of the yellow and pink inflorescence.

In countries with a climate similar to that of its country of origin it can become a serious pest can push out native vegetation. It has invaded many parts of India, Australia and Africa. A farmer in Zimbabwe whom I was visiting many years ago had to use tractors to pull out the large lantana bushes that had taken over some of his fields.

The plant is slightly toxic and animals can become ill after eating it. Its berries are edible although they are toxic when still green.

A plus point for this species is that it’s flowers attracts many butterflies, moths and bees. In the United States it is often planted in butterfly gardens. I often spend a long time taking pictures of insects visiting the flowers of a lantana hedge at Buskett Gardens.

In parts of India the stalks of the lantana are now being used to make household furniture while the smaller branches are tied together to make brooms. Lantana is also used in herbal medicine. Leaf extracts are said to have antimicrobial, fungicidal and insecticidal properties. 

This article was published in The Times on 13.12.10


As autumn turns to winter one starts seeing less insects in the countryside. Last Sunday while taking pictures at Selmun the only insects I saw in any number were grasshoppers. Several jumped into the large spaces between the stones of an old wall and walked slowly on the white limestone dust into the inner part of the wall until they disappeared from view. 

Grasshoppers overwinter as eggs, nymphs or adults so the ones I was observing could be looking for a suitable place to lay eggs or to hibernate.

Grasshoppers are familiar insects with short antennae and large hind legs. Sometimes the hind legs have short projections that are rubbed against the lower edges of the forewing to make a noise during the day. The legs are hard and can exert a lot of force and this gave rise to the idea in Malta that grasshoppers are armed with a knife which they use for self defense.

It is estimated that there are about 11,000 species of grasshopper in the world. Most live in tropical areas especially in rain forests. About 25 species are found in the Maltese islands. Some species are very common and you will see them jumping away from you wherever you walk in the countryside. Most are greyish brown and blend perfectly well with their surroundings. 

Some species have brightly coloured hind wings which are normally kept hidden under the forewings. They are uncovered only when they are flying. Te bright colours have an important function. 

When danger approaches these insects rely on their excellent camouflage for protection but if a predator approaches too closely they fly away startling their enemy with their bright colour for long enough to be able to fly away. They do not fly very far away but as soon as they land they disappear again.

Grasshoppers eat mostly vegetation and some species can become pests.

They have an incomplete metamorphoses as when they hatch the young look like small wingless adults which grow progressively larger as they break out of one exoskeleton after the other until they reach adulthood.

In Africa and in other parts of the world where they occur in large numbers, grasshoppers can be an important source of proteins, minerals and vitamins especially in times of food shortage. 

This article was pubished in The Times on 8.12.10

Sunday, January 23, 2011

The tree house leek first grown as a house plant

Tree house leek (Aeonium arboreum)
There are many species on non-indigenous plants in the Maltese countryside. 

These are native to other countries but have established themselves and become naturalised in the Maltese islands. Many of them were brought to Malta as garden plants 

The Cape sorrel, (ħaxixa ngliża) was grown at the Argotti Gardens in Floriana at the beginning of the nineteenth century . It is a native of South Africa but found the conditions in the Maltese countryside to be so favourable that after a short while it established itself in the Maltese countryside and became very common everywhere.

Another alien species is the tree house-leek which is known in Maltese as kalluwa

This species was first grown in Malta as a garden plant. It was often planted close to farmhouses and eventually started to grow wild in the Maltese countryside.

 It is now considered as a naturalised alien species. It is a succulent, subtropical member of the genus Aeonium. 

This name is derived from the ancient Greek word aionos which means immortal. This genus consists of about thirty-five species most of which are native to the Canary Islands. A few species are found in Madeira, Morocco and in eastern Africa. 

The climate of the Canary Islands is fairly similar to that of the Mediterranean and many of the species manage to grow very well in Mediterranean countries including Malta.

Between the end of December and late February the tree house-leek produces a large number of bright yellow flowers that grow on an ovoid structure. The leaves are attached to the main stem and grow wrapped around it to form a rosette.

The tree house-leek is the most commonly cultivated aeonium.

 In winter it produces numerous bright yellow flowers on compact ovoid structures. Several varieties and hybrids exist including some with brown or variegated leaves. In gardens they can grow up to two metres but in Malta I have never seen a plant more than one metre high.

This article was published in the Times on 1.12.10

The unusual friar's cowl

Friar's Cowl (Arisarum vulgare)
The friar’s cowl is an unusual plant found throughout the Mediterranean region.

 I am sure that whoever gave it its name in English was a religious person who got his inspiration from the monks and friars’ habit. In Maltese this plant is called garni tal-pipi which can be translated as smoking pipes’ arum.

It is a member of the arum family. Other members of this family include the Italian lord and ladies (garni) a common species that flowers in early spring.

The friar’s cowl is a perennial that is it can live for more than one year although during the summer months it can be found only as an underground tuberous rhizome. 

In autumn the rhizome grows new leaves and a short while later a flower appears above the surrounding vegetation. The flower is brown with a curved tongue-like structure growing out of it. The flower is surrounded by a tubular leave whose top part is shaped like a hood.

 This is the part we normally see. This leave has many dark spots that resemble ants. It is believed that these are a part of the defence system of the plant as it is a form of visual insect mimicry that serves as an herbivore repellent. This structure is so unusual and beautiful that I do not tire of taking pictures of it.

The friar’s cowl flowers throughout autumn and winter. 

In North Africa the rhizomes are used as food. Before being eaten the rhizomes must be washed in copious amounts of water to remove needle-like crystals of calcium oxalate which produce pain when they come in contact with the lips, tongue or skin. Cooking can also remove the effect of these crystals. It is also claimed that parts of the plant can are used to treat ear and spleen tumours.

This article was published in The Times on 24.11.10

Three species of hawk moths in different localities

Caterpillar of the Convolvulus Hawk moth (Agrius convolvuli)
In the past few days I found the caterpillars of three species of hawk moths in different localities around Malta. They belonged to the death’s head hawk moth, the convolvulus hawk moth and the Maltese spurge hawk moth. The first two are the largest moths in the Maltese islands. 

Hawk moths are medium sized to large moths with narrow wings and streamlined abdomens that make it possible for them to fly rapidly and for long distances. Some hawk moths can fly at 50 kilometres per hour and are among the fastest insects.

The convolvulus hawk moth is found throughout Europe and Africa. Its caterpillar (photograph) feeds on bindweeds which are known scientifically as Convolvulaceae hence the English name of this moth. 

In Maltese it is known as baħrija tal-leblieb. Leblieb is bindweed in Maltese. 

The caterpillar of this species, like that of most other hawk moths, has a horn-like structure at the posterior end of its body. It is dark in colour unlike the caterpillars of the two other species I found which are both very brightly coloured. 

The caterpillar of the convolvulus was crossing a path at Il-Majjistral Park. It was probably searching for a place to pupate. Hawk moths spend the winter months as a pupa.

 Before turning into a pupa the caterpillars of these moths burrow into the soil and remain under the surface or in a small chamber until they metamorphose into an adult moth. In topical species the change can take place in about three weeks but in colder parts of the world the adult emerges in spring or summer.

The adult convolvulus moth  is grey with pink, black and white spots on both sides of the abdomen. It spends the day on a wall or tree bark where it can be very well camouflaged. When disturbed it humps its thorax to scare any predator away.

This article was published in The Times on 10.11.10