Page 56 - Tạp chí bonsai cây cảnh BCI 2015Q2

SPECIES GUIDE: Casuarina Equisetifolia

By Archana Gupta, Sujata Bhat, Nikunj Parekh and Jyoti Parekh, India

Common Names: he first finer needle Casuarina came to India spray is good for the bonsai plant or a potted tree. Casu-
casuarina some two decades back as a gift from none other arina can bear temperatures of 10–35 °C, annual rainfall
coast sheoak Tthan our friend from Indonesia, Budi Sulistyo, of 200–500 mm. It tolerates slightly alkaline and calcar-
coast she oak which is of historical importance. Large numbers of eous soil but is intolerant to prolonged water logging.
coastal she-oak) the fine needle Casuarina that are now seen in India
beach casuarina are nursery grown and not yamadori. These were then Casuarina as a Bonsai
beach oak made affordable and reached all nooks and corners of Casuarina was first introduced as bonsai in Indonesia
beach sheoak peninsular coastal India. where Casuarina equisetifolia mostly grows along the
beach she-oak Casuarina is a genus of shrubs and trees in the fam- coastline of this island. Excessive pruning and cutting of
whistling tree ily Casuarinaceae, growing in sub-tropical and tropical these trees resulted in stunted trees that attracted bonsai
horsetail she oak coastlines of Australia and islands of the Pacific, and enthusiasts who started collecting them as bonsai mate-
horsetail beefwood widely spread to Hawaii, Florida, India, Indonesia, Ma- rial. Pruning techniques of the foliage were developed
horsetail tree laysia, Thailand, Africa, Egypt, some part of China and which made the Casuarina resemble pines. Casuarinas
Australian pine Japan, Caribbean islands etc. Commonly known as She- are amenable to all styles of bonsai either as individual
ironwood oak or Australian pine because the branches and scale- trees or in groups.
whistling pine like “needle” leaves bear a superficial resemblance to the
Filao tree pines. In India it is commonly called Jungli saru, Jungli Propagation
agoho Zhao or Vilayati saru. The Indian Casuarina has coarser, Casuarina can be easily propagated by seed, stem cut-
thicker and longer branches with darker green color as ting and air layering. The success rate of stem cutting
compared with the Indonesian variety. and air layering is quite high and rapid.
Casuarina grows in subtropical and tropical, both When collected from the wild as yamadori, the trees
at the seashore in dry, salty, calcareous soils and up in can be extremely sensitive due to drastic disturbance of
the mountains in high rainfall area on volcanic soils. the root system. It is then advisable to cut a minimum
Although considered as invasive species in many coun- portion of the root ball and treat the roots with a hor-
tries, some are introduced and planted as windbreaks mone solution that will help revive the tree in the pot. It
in windswept areas. is also advisable to keep the original soil as much as pos-
sible. After potting, keep the plant in a shady place until
Plant Description: the plant revives and new sprouts develop before moving
Casuarinas are large deciduous trees reaching heights it out under the full sun. Care should be taken to ensure
of up to 35 meters with finely branched crowns that that the potted plant should not be over watered, but
flatten with age. The trunk is often straight; cylindri- misting of the tree to keep up humidity levels is advisable.
cal in diameter measuring 100–150 cm. Branches are Casuarina equisetifolia grows along the sandy coast-
drooping, needle-like, and gray-green in color. The line with strong winds and sunlight, the same climatic
highly reduced tooth-like leaves are in whorls of seven and soil conditions are applicable for bonsai as well.
to eight per node. Shady conditions will cause slow growing; the branches
Flowers are unisexual with two bracteoles. Male flow- are weak and droopy and unhealthy. The soil should be
ers occur as terminal, simple elongated spikes borne in highly porous to allow for good drainage. We use about
whorls with a single stamen. Female flowers are borne 60–70% sand and the rest humus as potting medium.
on short, lateral branchlets and are cylindrical or cone- Porous structure of the soil is extremely important for
shaped. Casuarina trees are either monoecious or di- the root hairs to develop. The sandy soil with humus
oecious. Casuarina equisetifolia is monoecious which ensures that the soil retains its moisture content. Indo-
means that they bear both the male and female flowers nesian bonsai experts recommend soil that is acquired
on the same plant. from volcanic mountains which is porous. In India, we
The fruit is a woody, oval structure superficially have experimented by breaking and crushing burnt
resembling a conifer cone made up of numerous car- coke, which has a granular structure and helps provide
pels each containing a single seed with a small wing good drainage.
called Samara. The generic name is derived from
the Malay word for the cassowary or kasuari, alluding Styling and Pruning Techniques.
to the similarities between the bird’s feathers and the When a Casuarina tree is first styled, it is advisable to
plant’s foliage. cut back all the branches to the level of the trunk. This
Casuarinas are found in semi-arid and sub-humid is preferably done during the growing season. When
climates. It is the only wooded tree that grows over a cut back, the trunk develops a mass of branches so that
ground cover of dune grasses and salt-tolerant broad- new branches can be selected at appropriate points on
leaved herbs. This is one reason an occasional saltwater the trunk and developed further for a complete re-style

54 | BCI | April/May/June 2015