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abundant appear apple asparagus attained autumn bark beans bearer beds borecole branches Britain buds bulbs cabbage caterpillars cauliflower celery colour covered crop cultivated deep drills dung dwarf early earth eggs endive espaliers feet flavour flowers form roundish French frost fruit trees garden grafting green ground grow grown growth guano havo heat hence inches insects larva leaves less lime manure matter medium mode moth nonpareil November onions operation peach pear pease pippin plants pods pomologists potatoes pots produced propagated pruning pupa quality excellent quality first-rate quantity quince removed render ripen roots rows russet scion Scotland sea-kale season seed shallots shoots side soil sorts sowing sown species spinach spring stem sufficient summer supply surface taken tion transplanting Tree hardy truffle tubers turnip variety vegetable winter wood yellow young
Página 265 - ... matter, which mixes with the earthy materials of the rock ; in this improved soil more perfect plants are capable of subsisting ; these in their turn absorb nourishment from water and the atmosphere; and after perishing, afford new materials to those already provided : the decomposition of the rock still continues ; and at length by such slow and gradual processes, a soil...
Página 362 - ... provided a plant is in health, in short tufts, and each terminated by a spongiole, are much more easily taken out of the ground without injury than if they were longer and more scattered among the soil. When destroyed, the spongioles are often speedily replaced, particularly in orchard trees, provided a slight degree of growth continues to be maintained. This is one of the reasons why trees removed in October succeed better than if transplanted at any other time. The growth of a tree at that...
Página 305 - In sowing seeds for the purpose of procuring improved varieties, care should be had not only that the seeds be taken from the finest existing kinds, but also that the most handsome, the largest, and the most perfectly ripened specimens should be those that supply the seed. A seedling plant will always partake more or less of the character of its parent, the qualities of which are concentrated in the embryo when it has arrived at full maturity.
Página 14 - Such excretions are most abundant immediately before the formation and during the continuance of the blossoms; they diminish after the development of the fruit Substances containing a large proportion of carbon are excreted by the roots and absorbed by the soil. Through the expulsion of these matters, unfitted for nutrition, the soil receives again, with usury, the carbon which it had at first yielded to the young plants as food, in the form of carbonic acid.
Página 323 - But in regard to the liber, as this is confined to a narrow strip in both stock and scion, great care must be taken that they are both placed as exactly in contact with each other as possible, so that the line of separation of the wood and bark should, in both stock and scion, be accurately adjusted. The success of grafting depends very much upon attention to this. But there are other reasons why this accuracy in adjusting the line between the bark and wood of the stock and scion is so important....
Página 14 - Transformations of existing compounds are constantly, taking place during the whole life of a plant, in consequence of which, and as the results of these transformations, there are produced gaseous matters which are excreted by the leaves and blossoms, solid excrements deposited in the bark, and fluid soluble substances which are eliminated by the roots. Such secretions are most abundant immediately before the formation and during the continuance of the blossoms ; they diminish after the development...
Página 363 - Cornus Mascula perspire twice its own weight in a day ; and Mr. Knight has remarked a Vine in a hot day losing moisture with such rapidity that a glass placed under one of its leaves was speedily covered with dew, and in half an hour the perspiration was running off the glass. In damp or wet weather this evaporation is least ; in hot dry weather it is greatest.
Página 282 - The process of burning renders the soil less compact, less tenacious and retentive of moisture ; and when properly applied, may convert a matter that was stiff, damp, and in consequence cold, into one powdery, dry, and warm ; and much more proper as a bed for vegetable life.
Página 282 - Lecture, are mixtures of the primitive earths and oxide of iron ; and these earths have a certain degree of attraction for each other. To regard this attraction in its proper point of view, it is only necessary to consider the composition of any common siliceous stone. Feldspar, for instance, contains siliceous, aluminous, calcareous earths, fixed alkali, and oxide of iron, which exist in one compound, in consequence of their chemical attractions for each other.