234 



FOREIGN NOTICES. 



are drawn forth, and the gum, becoming 

 less fluid, moves more slowly, and gradually 

 accumulates in, and obstructs the natural 

 passages ; while, in other parts, the tree 

 being subjected to more genial heat, a 

 more active circulation is maintained. The 

 consequence of which is an expansion, and 

 at last a bursting of the vessels through 

 which the sap flows, at those points where 

 the obstruction exists ; and then ensue 

 warts, or knobs, or an effusion of sap, and 

 eruptions of gum. Though this is only 

 theor}'-, and needs to be verified by actual 

 experiment and chemical research, yet it 

 derives support from the practice of many 

 gardeners. It has been stated on sufficient 

 authority that salt, applied to the soil about 

 a plum tree, will prevent the black wart. 

 If our argument be correct, the result of 

 the action of salt is obvious enough : the 

 tree receives in its system a solution of salt, 

 which, by its nature, attracts moisture, (or 

 gives greater fluidity to the sap,) and com- 

 municates it to the gum ; thus preventing 

 the concretion that would check circulation. 

 The cause of the disease (excessive heat,) 

 is not removed by the application of salt ; 

 but it acts as an indirect remedy; it alters 

 the secretions of the tree, so that the same 

 cause does not produce the same effect. 



We are aware, that plants brought into 

 a condition contrary to their nature lose, to 

 some extent, their vital powers; and that, 



in consequence, a formation of slime-sugar 

 (saccharum mucosurn) takes place. It al- 

 ways follows a great decrease of phlegm, 

 (principium mucosurn,) which last substance 

 abundantly exists in peach, plum, and cher- 

 ry trees. In the capacity of the plant to 

 produce slime-sugar at the approach, or, 

 rather, in a certain stage of disease, we 

 see how nature provides the means of ac- 

 complishing her ends, since the reduction 

 of the plant to dust (its last destination, in 

 the usual order of things,) is brought about 

 by decay, and the first step towards decay 

 is fermentation. Nature, then, has recourse 

 to that powerful principle of fermentation — 

 slime-sugar — to begin fermentation, and 

 that the taste and odor of this substance 

 will summon to its aid those additional 

 agents of destruction, — insects. When, 

 therefore, we perceive, on diseased fruit 

 trees, swarms of insects, let us not confound 

 the effect with the cause, but rather attri- 

 bute their presence to the disease, than the 

 disease to their presence. H. J. Ehlers, 



Landscape Gardener. 

 Barryloivn, JV. Y., Oct., 1849. 



[The foregoing suggestions are quite new 

 to us, and come from one of the most intel- 

 ligent German gardeners in the country. 

 They appear to us to be worthy of the seri- 

 ous attention of our physiological readers, 

 interested in the diseases of stone-fruit 

 trees. Ed.] 



FOREIGN NOTICES. 



Green-house and Window Gardening. — 

 Housing. — Nurserymen in all parts of the kingdom 

 are now busy among their young stock preparing 

 for " housing" it, by which term they describe 

 putting plants under glass. You may st>e rows 

 of men at this work in every great nursery, and 

 there the division of labor is carried out to a great 

 extent. The first person takes up the pot, raps 

 the edge of it on something solid — sometimes on 

 his own knee, or against the point of his shoe, or, 



what is not a bad contrivance, against the tread, 

 or shoulder, of the blade of a spade stuck firmly 

 in the ground beside him for the purpose. This 

 first move is, or should be, done rapidly, and is 

 intended to look out for worms which may have 

 got access to the pot, and if they got the least 

 warning of approaching danger you lose sight of 

 them for that day. The next move is to see that 

 the drainage is perfect, and a little adjustment, of 

 the crockSj if needs be, will scon put that right. 



