262 THE YEAR-BOOK OF AGRICULTURE. 



days travelling up the rivers without seeing any striking flowering tree or shrub. This is 

 partly owing to the flowers of most tropical trees being so deciduous ; they no sooner open 

 than they begin to fall ; the Melastomas, in particular, generally burst into flower in the 

 morning, and the next day are withered, and for twelve months that tree bears no more 

 flowers. This will serve to explain why the tropical flowering trees and shrubs do not make 

 so much show as might be expected." 



The Ailanthus-tree. 



A CORRESPONDENT of the N. Y. Times furnishes the following statement respecting the dis- 

 tribution and propagation of the ailanthus-tree in the United States. They were imported 

 some fifty years since by a nurseryman in the vicinity of New York, at a time when there 

 was some excitement about manufacturing morocco leather, which previously had been im- 

 ported. This tree was imported as the one which furnished the material with which the im- 

 ported morocco leather was tanned. It was soon found that many species of the genus Rhus 

 growing in our country, all of which are more or less poisonous, answered equally as well as 

 the imported ailanthus for making the same leather; hence the demand for the imported 

 plant ceased; but they had been set in one corner of the gentleman's nursery, where they had 

 spread and became as great a nuisance as Canada thistles ; the inquiry then was how to get 

 them out of the ground. While the gentleman's son was pondering upon this business, he 

 thought he would try the effect of a puff direct; therefore he set himself to the task, and com- 

 menced by calling it " the tree of heaven," and gave a wonderful description of the beauty of 

 the tree changed the price from twenty-five cents to one dollar for each plant, and told the 

 writer that he sold off the next season five thousand dollars' worth of plants from the same 

 ground that previous to that puff he would have given one hundred dollars to have cleared of 

 them. 



The gentleman's success in that one humbug encouraged him to try another with the same 

 plant. 



I think it was about the year 1847 or '48 that every postmaster in the United States re- 

 ceived a package of seeds of the ailanthus, containing one hundred and twenty-five seeds, 

 requesting them to sell one hundred of them at one cent each, and remit to a person named, 

 one dollar, and keep twenty-five seeds to pay them for their trouble ; at the same time de- 

 scribing it as one of the most splendid and valuable trees that had ever been discovered. 



So far as the writer was informed, about one-half of the postmasters remitted their dollar 

 forthwith, not knowing the tree in question. 



Rotation of Forest Trees. 



THERE are millions of acres of pine-forests which present an even surface for tillage, whose 

 improvement for continued and profitable cultivation is a matter of great moment. If their 

 virgin soils do not exhibit an acid reaction, they at least possess too little of alkaline ingre- 

 dients for high agricultural productiveness. We have been astonished at the benefits that 

 accrued from the application of marl and shell-lime to these virgin earths, in which there was 

 no lack of organic substances. Where the potash came from that existed in such large crops 

 of wheat and corn, appeared a mystery. Lime seemed to bring it out from its before insoluble 

 silicates. Indeed, we can account for the natural fertility in the southern peninsula of Mary- 

 hind, and those, districts of Virginia and Georgia where marl abounds, in no other way. In 

 an acre of wheat and corn there is five times more potash than lime ; while the amount of 

 soluble potash in natural pine-bearing soils is exceedingly small. A pine-tree, when burnt, 

 yields but little ashes, and they are not rich in potash. Pine-leaves, however, yield, pound 

 for pound, twelve times more ashes than pine-wood ; and it is mainly the annual fall of leaves 

 on the surface of the ground, giving alkalies drawn from the deep subsoils, as well as organ- 

 ized carbon, oxygen, and hydrogen, that enriches the land. By adding a little lime to this 

 natural source of fruitfulness, the owner of pine-leaves will greatly enhance their value. 

 They can be changed permanently from the production of coniferous plants to that of cereals 



