The Gymnosperms are an economically important group of plants. The tress are used for landscaping, timber, building construction, resin and for the manufacture of board and paper. They are also used as food and used in medicines, perfumes, varnishes and essential oils.
Ornamental Plants:
Different species of gymnosperms are used as ornamental plants. As they are evergreen, stately appearance, symmetrical growth are treat to eye. Different species of Cycas, Ginkgo, Abies, Araucaria, Thuja,Taxus are grown as ornamental plants. Cupressus funebris is generally planted around tombs and religious buildings.
Previously Juniperus virginiana was decorated as Christmas tree, but now Picea and Aibes are ceremoniously used as Christmas trees.
Timber or Wood Yielding Plants:
Majority of the conifers posses a light coloured, light-weighted and straight grained wood. The wood lacks xylem fibres but has more cellulose. Therefore, it has a softer texture.
1. Abies alba is the largest timber producing tree of Europe. It is used in carpentry.
2. Agathis australis is chief timber tree of New Zealand and Australis. It is useful in building constructions, boats, and wooden machinery.
3. The wood of Juniperus procera and J. bermediana is durable and strong. It is used for pencil making, ship building, posts and carpentry. J. wallichiana wood is used as fuel and as incense in Buddhist temples.
4. The heart wood of Cedrus deodara is very strong and scented. The wood is resistant to insect attack due to the presence of oil. It is used form making doors, poles, railway sleepers and flooring.
5. The wood of Podocarpus is valued for plywood making.
6. The wood of Dacrydium is very hard and highly inflammable. It is used form construction, furniture, indoor finish, railway sleppers.
7. Picea wood is white or pink, smooth and soft. So it is usd in making musical instruments like piano, violin etc.
Resins:
Resins are plant exudates which make the wood resistant to decay. Conifers are amongst the major resin yielders of the world.
Resins are insoluble in water, but readily soluble in organic solvents. The various kinds of resins are:
Copal: it is a type of hard resin which contain little essential oil. It is much valued in varnish industry because of high melting point and hardness. Copal obtain from the fossil stems of Agathis australis is called Kauri copal or Kauri gum. Agathis alba provides East Indian Copal or Manila Copal.
They are used in spirit varnishes and in making linoleum, preparation of plastics, printing inks and water proof compounds. The resin of Araucaria angustifolia is mixed with wax to make candles.
Sandarac: It is hard, yellow resin obtained from Tetraclinis articulate and Callitris sp. It is used as metal varnish giving good lustre and as paper and leather varnish. It is also used as pill varnish in pharmaceuticals. Also used in the preparation of incense or Dhoop. Mastic sandarac is used to preserve ancient photos and also used as filling form dental cavities.
Canada balsam: The resin obtained from Abies balsmae is known as Canada balsam. It has a high refractive index and donot crystallise or granulate on drying. Hence, it is used as mounting medium in slide preparation for microscopic objects.
Amber: it is a fossil resin obtained from the fossil member Pinus succinifera. It occurs near the Baltic, Sicily, Madagascar islands.
Amber is yellow brown to black, hard and brittle with an aromatic odour. Amber is used in medicine and X rays. Laboratories and hospitals keep blood in amber containers, because amber does not permit the blood to coagulate. It is used to manufacture cigarette holders, mouth pieces of smoking pipers, beads and small ornaments.
Food
Young leaves of Cycas and Gnetum are used as vegetab les in various countries
Cycads are used as a source of starch either from the stem pith or from the seed kernels. The stem starch is called as sago. It is mainly obtained from Cycas circinalis, C. rumphii, C. revolute.
Seeds of Araucaria, Ginkgo biloba are roasted and eaten in Chile and Japan.
Medicinal Uses:
The alkaloid ephedrine is extracted from the Ephedra sinica, E.equisetina. Ephedrine is an important ingredient in cough syrups because of its action in dilations of bronchial tubes.
The leaves of Taxus baccata are used in asthma, bronchitis, epilepsy and for indigestion. The plant contains a toxin taxine, which is an active heart poison.
Another alkaloid Taxol obtained from Taxus brevifolia is effective against ovarian cancer, breast cancer, melanoma.
The leaf extracts of Ginkgo biloba prevent the blood clotting. Hence, they are used in the treatment of cerebral insufficiency and vertigo.
Oil of Juniperus oxicidrum is used to cure skin diseases and eczema.
The Gymnosperms are an economically important group of plants. The tress are used for landscaping, timber, building construction, resin and for the manufacture of board and paper. They are also used as food and used in medicines, perfumes, varnishes and essential oils.
Ornamental Plants:
Different species of gymnosperms are used as ornamental plants. As they are evergreen, stately appearance, symmetrical growth are treat to eye. Different species of Cycas, Ginkgo, Abies, Araucaria, Thuja,Taxus are grown as ornamental plants. Cupressus funebris is generally planted around tombs and religious buildings.
Previously Juniperus virginiana was decorated as Christmas tree, but now Picea and Aibes are ceremoniously used as Christmas trees.
Timber or Wood Yielding Plants:
Majority of the conifers posses a light coloured, light-weighted and straight grained wood. The wood lacks xylem fibres but has more cellulose. Therefore, it has a softer texture.
1. Abies alba is the largest timber producing tree of Europe. It is used in carpentry.
2. Agathis australis is chief timber tree of New Zealand and Australis. It is useful in building constructions, boats, and wooden machinery.
3. The wood of Juniperus procera and J. bermediana is durable and strong. It is used for pencil making, ship building, posts and carpentry. J. wallichiana wood is used as fuel and as incense in Buddhist temples.
4. The heart wood of Cedrus deodara is very strong and scented. The wood is resistant to insect attack due to the presence of oil. It is used form making doors, poles, railway sleepers and flooring.
5. The wood of Podocarpus is valued for plywood making.
6. The wood of Dacrydium is very hard and highly inflammable. It is used form construction, furniture, indoor finish, railway sleppers.
7. Picea wood is white or pink, smooth and soft. So it is usd in making musical instruments like piano, violin etc.
Resins:
Resins are plant exudates which make the wood resistant to decay. Conifers are amongst the major resin yielders of the world.
Resins are insoluble in water, but readily soluble in organic solvents. The various kinds of resins are:
Copal: it is a type of hard resin which contain little essential oil. It is much valued in varnish industry because of high melting point and hardness. Copal obtain from the fossil stems of Agathis australis is called Kauri copal or Kauri gum. Agathis alba provides East Indian Copal or Manila Copal.
They are used in spirit varnishes and in making linoleum, preparation of plastics, printing inks and water proof compounds. The resin of Araucaria angustifolia is mixed with wax to make candles.
Sandarac: It is hard, yellow resin obtained from Tetraclinis articulate and Callitris sp. It is used as metal varnish giving good lustre and as paper and leather varnish. It is also used as pill varnish in pharmaceuticals. Also used in the preparation of incense or Dhoop. Mastic sandarac is used to preserve ancient photos and also used as filling form dental cavities.
Canada balsam: The resin obtained from Abies balsmae is known as Canada balsam. It has a high refractive index and donot crystallise or granulate on drying. Hence, it is used as mounting medium in slide preparation for microscopic objects.
Amber: it is a fossil resin obtained from the fossil member Pinus succinifera. It occurs near the Baltic, Sicily, Madagascar islands.
Amber is yellow brown to black, hard and brittle with an aromatic odour. Amber is used in medicine and X rays. Laboratories and hospitals keep blood in amber containers, because amber does not permit the blood to coagulate. It is used to manufacture cigarette holders, mouth pieces of smoking pipers, beads and small ornaments.
Food
Young leaves of Cycas and Gnetum are used as vegetab les in various countries
Cycads are used as a source of starch either from the stem pith or from the seed kernels. The stem starch is called as sago. It is mainly obtained from Cycas circinalis, C. rumphii, C. revolute.
Seeds of Araucaria, Ginkgo biloba are roasted and eaten in Chile and Japan.
Medicinal Uses:
The alkaloid ephedrine is extracted from the Ephedra sinica, E.equisetina. Ephedrine is an important ingredient in cough syrups because of its action in dilations of bronchial tubes.
The leaves of Taxus baccata are used in asthma, bronchitis, epilepsy and for indigestion. The plant contains a toxin taxine, which is an active heart poison.
Another alkaloid Taxol obtained from Taxus brevifolia is effective against ovarian cancer, breast cancer, melanoma.
The leaf extracts of Ginkgo biloba prevent the blood clotting. Hence, they are used in the treatment of cerebral insufficiency and vertigo.
Oil of Juniperus oxicidrum is used to cure skin diseases and eczema.
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