This document provides important guidelines for caring for bonsai plants, including avoiding choosing plants with large leaves, flowers, or fruits; using styles unsuitable for the species; using blunt cutting tools; unnatural decorations; being impatient for flowers or fruits before shaping; mixing chemicals and fertilizers; keeping bonsai on the ground; tying wire too tightly; retaining wires too long; hard pruning of conifers; heavy fertilization; and unnatural appearances.
Choose plants suitable for the local climate and position them correctly in containers with adequate drainage. Care for bonsai by pruning regularly, providing balanced nutrition with fertilizer, plenty of sunshine, and thorough watering until it drains. Inspect frequently for pests and diseases, and develop a natural-looking design that is well-balanced through constant care and affection.
Planting times for certain crops are February through March and July through August. Seeds can be sown in early spring from February to March or during the summer months from July to August.
The document discusses a demonstration on Juniper bonsai trees that will take place in Columbia. Juniper bonsai are a popular type of bonsai tree that can be styled and shaped through careful pruning and training. The demonstration will cover basic bonsai techniques for caring for and maintaining Juniper bonsai trees.
This document lists the essential equipments and tools needed for bonsai, which includes a plant, pots of various shapes with drainage holes, a potting mixture of soil, sand and leaf mould, potting sticks, sieves, copper wire of varying thickness, wire cutters, pruning knives and secateurs, and watering equipment like a can and tub.
This document lists important plant species for growing bonsai in hilly areas, including Araucaria, Aucuba, Azalea, Camellia, Chinese hat, Coral tree, Cryptomeria, Cypress, Flame of the forest, Ginkgo, Juniper, Koelreuteria, Maple, Magnolia, Plane tree, Peach, Pines, Podocarpus, Sal, Silver fir, Spruce, Taxus, Thuja, Willows, and Zanthoxylum.
This document lists important plant species that are suitable for bonsai, including trees, shrubs, and bamboo. Some recommended species are amaltas, araucaria, babul, bamboo, banyan, ber, bottle brush, bougainvillea, casuarina, cherry, Chinese orange, coranda, cryptomeria, deodar, duranta, excoecaria, gulmohar, hibiscus, ixora, jacaranda, Java fig-tree, murraya, malpighia, oleander, peach, pines, pilkhan, pipal, plum, prosopis, silver oak, tamarind.
Propagation of plants can be done through seeds, cuttings, layering, grafting, or buying seedlings from a nursery. Some plants can also be propagated through collection from seeds or cuttings found in forests or fields.
Selection of plants for bonsai requires choosing species that can thrive in confined spaces with minimal resources. Good options are plants with small flowers and fruits that allow foliage to reduce to a quarter of its normal size, or those bearing flowers on leafless branches. The selected plant must be able to withstand stress from a small pot and low nutrients.
Pruning and trimming helps develop trees into attractive shapes by restricting growth and maintaining a proper balance between roots and shoots. It involves regularly cutting no more than 1/3 of roots or shoots to reduce growth in a controlled manner. Proper pruning techniques help develop good structure and form for trees.
Ideal nutrition for bonsai includes sludge or well rotten cow dung slurry mixed with groundnut, cotton, or neem cake allowed to ferment for a month before diluting. This mixture is given twice a month along with bone meal and single super phosphate, which are also very beneficial.
Growing media for bonsai should be coarse and well-drained to provide water, oxygen, and nutrients. An ideal medium consists of equal parts soil, leaf mold, and crushed brick or sand. The top layer needs sufficient humus, while conifer plants do better in drier soil and fruit trees prefer more humus-rich soil.
This document provides important guidelines for caring for bonsai plants, including avoiding choosing plants with large leaves, flowers, or fruits; using styles unsuitable for the species; using blunt cutting tools; unnatural decorations; being impatient for flowers or fruits before shaping; mixing chemicals and fertilizers; keeping bonsai on the ground; tying wire too tightly; retaining wires too long; hard pruning of conifers; heavy fertilization; and unnatural appearances.
Choose plants suitable for the local climate and position them correctly in containers with adequate drainage. Care for bonsai by pruning regularly, providing balanced nutrition with fertilizer, plenty of sunshine, and thorough watering until it drains. Inspect frequently for pests and diseases, and develop a natural-looking design that is well-balanced through constant care and affection.
Planting times for certain crops are February through March and July through August. Seeds can be sown in early spring from February to March or during the summer months from July to August.
The document discusses a demonstration on Juniper bonsai trees that will take place in Columbia. Juniper bonsai are a popular type of bonsai tree that can be styled and shaped through careful pruning and training. The demonstration will cover basic bonsai techniques for caring for and maintaining Juniper bonsai trees.
This document lists the essential equipments and tools needed for bonsai, which includes a plant, pots of various shapes with drainage holes, a potting mixture of soil, sand and leaf mould, potting sticks, sieves, copper wire of varying thickness, wire cutters, pruning knives and secateurs, and watering equipment like a can and tub.
This document lists important plant species for growing bonsai in hilly areas, including Araucaria, Aucuba, Azalea, Camellia, Chinese hat, Coral tree, Cryptomeria, Cypress, Flame of the forest, Ginkgo, Juniper, Koelreuteria, Maple, Magnolia, Plane tree, Peach, Pines, Podocarpus, Sal, Silver fir, Spruce, Taxus, Thuja, Willows, and Zanthoxylum.
This document lists important plant species that are suitable for bonsai, including trees, shrubs, and bamboo. Some recommended species are amaltas, araucaria, babul, bamboo, banyan, ber, bottle brush, bougainvillea, casuarina, cherry, Chinese orange, coranda, cryptomeria, deodar, duranta, excoecaria, gulmohar, hibiscus, ixora, jacaranda, Java fig-tree, murraya, malpighia, oleander, peach, pines, pilkhan, pipal, plum, prosopis, silver oak, tamarind.
Propagation of plants can be done through seeds, cuttings, layering, grafting, or buying seedlings from a nursery. Some plants can also be propagated through collection from seeds or cuttings found in forests or fields.
Selection of plants for bonsai requires choosing species that can thrive in confined spaces with minimal resources. Good options are plants with small flowers and fruits that allow foliage to reduce to a quarter of its normal size, or those bearing flowers on leafless branches. The selected plant must be able to withstand stress from a small pot and low nutrients.
Pruning and trimming helps develop trees into attractive shapes by restricting growth and maintaining a proper balance between roots and shoots. It involves regularly cutting no more than 1/3 of roots or shoots to reduce growth in a controlled manner. Proper pruning techniques help develop good structure and form for trees.
Ideal nutrition for bonsai includes sludge or well rotten cow dung slurry mixed with groundnut, cotton, or neem cake allowed to ferment for a month before diluting. This mixture is given twice a month along with bone meal and single super phosphate, which are also very beneficial.
Growing media for bonsai should be coarse and well-drained to provide water, oxygen, and nutrients. An ideal medium consists of equal parts soil, leaf mold, and crushed brick or sand. The top layer needs sufficient humus, while conifer plants do better in drier soil and fruit trees prefer more humus-rich soil.
This document discusses a landscaping style using cascading plants with variegated star jasmine. Cascade style landscaping features plants hanging over walls or spilling out of containers to create a sense of movement. Variegated star jasmine is recommended as it has green and white variegated leaves and fragrant white flowers that bloom throughout the summer. This combination provides visual interest and fragrance.
1. CHAPITRE 1. OPTIQUE CLASSIQUE 1.5. OPTIQUE GÉOMÉTRIQUE
Par ailleurs, les deux triangles hachurés sont aussi
semblables. On peut donc aussi écrire :
hobjet
himage
= f
di − f
Ainsi, on tire :
do
di
= f
di − f
)
di − f
f
= di
do
)
di
f
− 1 = di
do
)
1
f
−
1
di
=
1
do
)
1
f
=
1
do
+
1
di
Ce qu'il fallait démontrer.
1.5.3 Grandissement
On a vu que du triangle grisé de la gure 1.31, on
tire :
hobjet
himage
= do
di
Cependant, pour tenir compte du fait que l'image
se trouve sous l'axe optique, on va donner un signe
négatif à di :
hobjet
himage
= do
−di
= −
do
di
Ainsi, on peut dénir le grandissement (et non le gros-sissement)
de l'image m par :
m = himage
hobjet
= −
di
do
(1.4)
1.5.4 Grossissement
Le grandissement est donc le rapport de la hau-teur
de l'objet à la hauteur de l'image. Or, la taille
de l'image est inversément proportionnelle à la dis-tance
à l'objet. Ainsi, si ce dernier est très éloigné,
l'image sera très petite et le grandissement vraiment
très petit.
Pourtant, une personne assez proche de l'image pour-rait
la voir plus grosse que l'objet. Ainsi, le grossis-sement
d'un objet n'est pas son grandissement.
Pour dénir le grossissement d'un objet, il faut le rap-porter
aux angles qui soustendent l'objet et l'image.
Car, ce sont ceux-ci qui vont rendre compte de notre
perception du grossissement. Par dénition, le gros-sissement
est déni par :
G = ¯
® (1.5)
où l'angle ® est celui sous lequel on voit l'objet et
l'angle ¯ celui sous lequel on voit l'image. Chacun
de ces angles peuvent facilement être calculés à l'aide
des relations trigonométriques suivantes :
tan(®) = hobjet
do
et tan(¯) = himage
di
où do est la distance de l'÷il à l'objet quand on le voit
sans lentille. Pour un ÷il normal, elle vaut 25 cm.
Dans le cas de petits angles (en radians), les relations
ci-dessus peuvent s'écrire :
® = hobjet
do
et ¯ = himage
di
1.5.5 La puissance d'une lentille
Parfois au lieu d'utiliser la distance focale d'une
lentille pour la caractériser, on utilise sa puissance
P :
P =
1
f (1.6)
Il s'agit de l'inverse de la distance focale. Son unité
est donc m−1 qui est dénie comme la dioptrie et
notée D.
Ainsi, la puissance d'une lentille d'une distance focale
de 20 cm, par exemple, vaux 5 dioptries :
P =
1
0, 2
= 5D
Notez que la distance focale doit être dans les unités
du système international, c'est-à-dire en mètre, pour
que la puissance soit en dioptries.
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