Introduction
Casuarina is a fast-growing evergreen tree. Its scientific name is Casuarina equisetifolia. Casuarina is believed to be derived from Latin word “casuarius” means ” a type of bird” from the resemblance of the branches to its feather. equisetifolia in other word it is called in name of “Horsetail tree” because of specific name equisetifolia is derived from the generic term Equisetum which meaning in Latin word “horsehair” i.e Horsetail. It is also known as Australian Whistling Pine for the noise made by the wind passing through its branches. It can survive up to 50 years in favorable climate. People cultivate casuarina as a wind break, in ornamental tree for the purpose to stabiles coastal sand and also providing excellent firewood. Most commonly planted in the coastal district of the state in area close to the sea on loose sand.
Common name
Australian pine, She oak, Beefwood, Horsetail tree, Casuarina, Whistling pine, Common iron wood, Scaly bark oak, Swamp oak, Gago, Gagu, Agoho, Agas, Ngas.
Native
Casuarina is native to Australia, Southeast Asia, India, Bangladesh and neighboring areas have been introduced into many countries.
Tree Height
This tree grows over 35meter and can attain up to 50meter with diameter of up to 100cm .
Stem
It has reddish brown to grey bark, the bark is rough, fibrous bark peeling in vertical stripes. Drooping branches, internode short and furrowed.
Leaves
The leaves of the casuarina are small scales on thin “needles like” branches. The leaves are so reduced that they look like whorls of tiny teeth and are barely visible as small scales forming a ring around the node between each segment. The number of teeth in each whorl reflect the number of leaves.
Flower
Casuarina blooms twice a year during February to April and September to October. Male and female flowers are presents on the same plant and are monoecious. Male flowers occur in terminal spike while the female flowers are in small, axillary cluster. Flowers are designed for the pollination by wind. The age of the first flowering varies from 2 to 5 years.
Fruit
Casuarina equisetifolia usually producing fruit twice a year i.e. June and December. In warm climate, flowering and fruiting occurs throughout the year and consequently, time of seed collection varies from place to place. The pre ripe fruit color for the genus is green to gray green, becoming brown when ripe, conelike structures are 5-7mm long that are 2cm long contained in woody and winged nutlets that each cone have one seed. The fruit on one do not all mature at the same time. Cone filled with seeds are important source of food for the birds such as cockatoos, finches and rainbow.
Seed
Each fruit filled with 70-90 winged seed. Female cone matures about 18-20weeks after anthesis and will release small, winged seeds with 3 days when dried under full sun. A kilogram of cones about 250 cones yields 20-60gm of seeds. So, for collection of seeds, ripe fruits are plucked from the branches before the cone dehisce, dried in sun and thrashed to separate the winged seeds. There are about 6,50,000-7,00,000 seeds/-Kg but on average only 2,70,000 of these are viable. The dried seeds retain viability for about 18month when its stores in airtight container.
Habitat
This plant can be found in tropical and sub-tropical areas around the world. Casuarina grows on the river banks, in the swamps and coastal regions. It thrives on clayey, loamy or sandy soil both in dry and wet area. Casuarina tolerates drought, seasonal flooding and moderate salinity of the ground and intolerant of frost. The casuarina grows quickly and achieve substantial heights, even in poor soil and when exposed to salt spray. Young seedlings are sensitive to water logging and fire.
Uses
The tree is very useful in agroforestry because of its ability to fix atmospheric Nitrogen, which is improve fertility of the soil, thanks to actinobacteria which lives inside nitrogen fixing root nodules. Which is essential nutrient for plants growth. it’s planted for retrieving and improving the land and use to protect from strong wind and even typhoon and tsunami as its branching pattern absorb wind impact quite well. The wood is dark brown, very hard and resistant to decomposition in soil or salt water for which it is used for house post, rafter, fences, Shingles, poles, tool handles and is almost unusable by carpenter. It has been called best firewood in the world because it immediately catches fire even when green and ashes retain heat for a long time and produce high quality charcoal. caloric value of the wood is 5000kcal/kg and that of charcoal exceeds 7000kcal/kg. Casuarina equisetifolia sheds many twigs throughout the year. it is used as a conservation measure to prevent erosion on coastline and along the edge of the estuaries.
Medicinal uses
Roots extracts are used for the treatment of dysentery, diarrhea and stomach-ache. A decoction of the twig is used for treating swelling. A decoction of the inner bark, combined with the inner bark of Terminal cattapa is taken for treatment for asthma and shortness of breath. the powder bark is used for treating pimple on the face. it is used in many pharmacological activities including antimicrobial, antidiabetic, antioxidant, cytotoxic, hypolipidemic, gastroprotective hepatoprotective and many other pharmacological effects. Although it has numerous health benefits, it is strictly mentioned to consult an Ayurvedic doctor or practitioner before consuming it. This is used for preserving rope etc. and contains red pigment, so it can be used as a dye.
Chemical constituent
Casuarina equisetifolia contained carbohydrate, alkaloids, proteins, glycosides, saponins, phenolics, flavonoids, Tannis, steroids, gum and tritepenoids. This bark contains 6-18% Tannis.
Propagation
Casuarina equisetifolia is most easily propagated by seed. Generally, no pretreatment is necessary for casuarina seeds. it can be directly sown in the raised mother bed having soil mixture (15cm thick) of sand and farmyard manure (FYM) or Cow dung manure (CDM) then covered a thin layer of sand. Seeds may be treated with fungicide (Bavistin) and soil mixture may be treated with insecticide like chlorpyriphos to keep away white ant and other insecticide attack. Organic pesticide is more suitable, and neem cake can also be useful as an organic pesticide. Seeds are normally sown so deep that the depth of the soil is not more than the diameter of the seed. the sand bed covered with straw to avoid Washing off seedling while watering. Since the seed bed is very minute and delicate, watering is to be done carefully in the regulated manner to prevent washout and damping off. Germination is usually complete within 2weeks after sowing of seeds. Application of Azotobacter bio fertilizers helps in promotion of root nodule and growth of the plant. Shade is to be provided in area with hot climate. We obtain 2 to 3 lakhs seedling from 1kg seed, it depends upon the climate and skilled of the worker engaged in this work. Seedling are transplanted to polypot when they are about 3-4cm in height.
Poly pots are filled with Soil, Sand & FYM in proportion of 1:2:1, Vermicompost/ neem oil cake /Azootabacter can be used as manure to an available extent as a substitute of FYM. Soil mixture may be treated with insecticide like chloropyriphos to prevent white ant attack. Organic pesticide is more desirable. the polypot are kept on polythene sheet to prevent root penetration into soil. Root cutting, grading, resetting of polypot seedling are done at a regular interval about 45days. Seedling are transplanted into container where they grown for 5-6 month to reach a height of 50-70cm, at which time they are transplanted to the field.
Pests and diseses
Casuarina equisetifolia is not prone to any serious pest and diseases except when grown in unfavorable conditions. Pests that attack the tree include crickets and grasshoppers, defoliator, stemborers and sap feeders. The major root diseases are caused by Pseudomonas solanacearum, Trichosporium vesiculosum and Rhizoctonia spp.
There is no effective control measure once infection occurred but for disease control, lopping and pruning of branches should be stopped to prevent primary establishment of disease. The stem canker and die back can be controlled by the application of Bavistin at 0.01 percent active ingredient or spray with mancozeb @0.25%.