August i, 1883.] 



THE TROPICAL AGRICULTURIST. 



93 



especially to bear pressuve, and by its soft and bright con- 

 sistence it sui-passes it considerably. 



Another use to which Tusser silk is put, is the making 

 of hearth-rugs, which, oa account of thicker fibres forms a 

 firmer ami softer sm-face. The price of spun Tusser thread 

 was in ls.'i2 11 shill. per pound, that of organ-silk and tram 

 of native reeled silk 7—10 shilUngs. 



The Chinese have also availed themselves of this Tusser 

 silk industry and are becoming dangerous rivals on account 

 of the cheapuess of mauual labour With them. Most of the 

 Tusser silk used in England and Mai-seilles is now imported 

 from China. 



By its gloss and sti-mgth Tusser silk is peculiaily adapted 

 for embroidery, when reeled from the cocoons as floss-silk. 

 Mr. Wardle has obtained e.'ccellent results by the combined 

 operations of printing and embroidering, which the Japanese 

 practise with so much success. 



Other wild species of silk-caterpillars are the Eria (Attac- 

 us riciuil on the Ricinus, the Moenga, on the Tjampaca- 

 trees (Michelia) the gigantic Attaous .Atlas, the -A. Tama- 

 Mai, tiie Acteas silenc, Attacus Edwai-dii, Antheraea Pero- 

 theti, A. Roylei, etc. 



Mr. Wardle is of opinion that also in our colonies wild 

 silk might be made a profitable affair. Many of the trees, 

 bearing these silk caterpillars in British India, growing also 

 wild in the Dutch Indies, so that surely peculiar kinds of 

 silk-yielding cateqjillars are indigenous there too. The treat- 

 ment might be effected by the natives at then- leisure, as 

 they would have nothing more to do than to take care to 

 collect the cocoons, and then to dispose of these to the 

 pm-chasers, while the mauufactuiing of the silk would have 

 to take place in separate estabUshments on a large scale. 

 The culture of the Siamese and the common s Ik-worm has 

 given no favourable results in .Java ; perhaps a better return 

 may be expected from e.tperiments with mdigenous sorts, 

 auLl especially by completely sep;u-ating the cultme, or col- 

 lecting, from the manufactm-ing. 



To all whom it may conceru, I can earnestly recommend 

 to make acquaintance mth Mr. W.ardle and with the rich 

 collection of Indian wild silks and stuffs made therefrom, 

 as exhibited in the Indian Department of the South-Ken- 

 sington Museum, and described in the following work publsh- 

 by that Society: IlaMl/iook of the Cdtection illustrative of 

 the n-i/d silks of India bi/ 'Th. Wayille, London, South- 

 Ken.siugton Mvsei'.m (price 1 one shilling). 



By the kindness of Jlr. Wardle a presentation-copy of 

 this book and half-a-dozen samples of silk have been received 

 in the Colonial Muse um in the pavilion at Haarlem. — F. W. 

 VAX Eeden. — Indian Mv.rcuii/. 



TREE PRUNING. 



Translated from the Fri-iich of A. des Care, lij Charles 

 .V. Sargent, professor of AihorieiUlure in Harvard College, 

 V. 3. ' 



Bark once injured or loosened can never attach itself 

 again to the trunk ; aud 'vhenever wounds, abrasuris, or 

 sections of loose bark exist on the trunk of a tree, the 

 damaged part should be cut away cleanly as far as the 

 injury esiends. Careful persons have been known to nail 

 on to a tree a piece of loosened bark, in the hope of 

 inducing it to grow again, or at least of retaining on the 

 youug wood its natural covering. Unfortunately the result 

 produced by this operation is exactly opposite to that 

 intended. The decaying wood and bark attract thousands 

 of insects, which find here safe shelter and abundant food; 

 and, iucreasiug rapidly, hasten the death of the tree. 



In such cases, instead of re-fastening the loosened bark 

 to the tree, it should be entirely cut away, care being 

 taken to give the cut a regular outline, especially on the 

 lower side ; for as has been already explained, if a por- 

 tion of the bark, even if adhering to the wood, is 

 left without direct communication with the leaves, it 

 must die and decay. -A. coating of coal-tar should, of cour.se, 

 be applied to such wounds. 



LuusKntd Bark. — i.i is necessary to frequently examine 

 the lower portions of the trunk, especially of trees begin, 

 uing to grow old; for here is often found the cau.sc of 

 death in many trees, in tin' large sheets of bark entirely 

 separated from the trunk. This condition of thin;;s, which 

 often cannot be detected except by the hollow sound pro- 

 duced by striking the tnuik with the back of the iron 



pruning knife, arrests the circulation of sap, while the 

 cavity between the bark and the wood furnishes a safe 

 retreat for a multitude of insects, which hasten the 

 destruction of the tree. The dead bark should be entirely 

 removed, even should it be ueces>ary in so doing to make 

 large wounds. Attention, too, shoukl be given to injuries 

 to the bark caused by tlie fall of neighbouring trees. These 

 may remain hidden for years, and are often only detected 

 by the peculiar sound pro^luced by a blow of the pruning 

 knife. Casi'S of this nature require the treatment recom- 

 mended for the last class. 



C'ltities ill the trunk. — Very often when a tree has been 

 long neglected, the trunk is seriously injured by cavities 

 cause! i-y the dtcay of de-id or broken branches. It is 

 not claimed tiiat pruning can remove defects of this 

 nature : it can with proper application, however, arrest 

 the progress of the evil, aud in such cases should always 

 be resorted to. The edge of the cavity should be out 

 smooth aud even, and all decomposed matter, or growth 

 ot new bark formed in the interior, should be carefully 

 removed. A coating of coal-tar should be applied to the 

 surface of the cavit^', aud the mouth plugged with a 

 piece of well-seasoned oak, securely driven into place. 

 The end of the plug should then be carefully pared 

 smooth and covered with coal-tar, precisely as if the 

 stump of a branch were under treatment. If the cavity 

 is too large to be closed in this manner, a piece of 

 thoroughly spasoned oak-board, carefully fitted to it, may 

 be securely nailed into the opening, and then covered 

 with coal-tar. It is often advisable to guard against the 

 attacks oi insects by nailing a piece of zinc or other 

 metal over the board, in such a way that the growth of 

 the new wood will in time completely over it. 



These operations resemble, if such a comparison is 

 admissible, the fillings performed by dentists, and with the 

 same object,^to check the progress of decay. 



The use of Coal-tar. — Coal-tar, a waste product of gas 

 works, is a dark-brown imperishable substance with the 

 dom" of creosote. It can be applied with an ordinary 

 painter's brush, aud may be used cold, except in very 

 cold weather, when it sboulil be sli^^htly war'iied before 

 application. Coal-tar has remarkable preservative proper- 

 ties, and may be used with equal advantage on living and 

 dead wootl. A single application without penetrating 

 deeper thcu or<liuary paint forms an impi-rvious coating 

 to the wood cells, which would without such covering, 

 under external influences, soon become channels of decay. 

 This simple application then produces a sort of instant- 

 aneous cauterization, and preserves from decay wounds 

 caused either in pruning or i>y accident. The odour of 

 coal-tar drives away insects, or prevents them, by complete 

 adherence to the wood, from injuring it. After lougand 

 expensive experiments, the director of the parks of the 

 city of Paris finally, in 186'. adopted coa'-tar in prefer- 

 ence to other preparations used for covering treewouud.s, 

 as may be seen in all the principal streets of the 

 capitid. 



Einplo.t/ment of Coal-tar on Fruit Trees.^lt is for this 

 reason that the application of coal-tar should not be made 

 except with considerable caution in the treatment of 

 wouuds on drupaceous fruit trees (cherries, peaches, plums, 

 &c.), and especially on the plum tree. It has often been 

 observed that the bark of fruit trees of this class have 

 suffcre 1 from the application of coal-tar. This is not the 

 case, l.owever, with pome-bearing trees (apples, prars, &c.); 

 to these coal-tar may be applied with perfect safety. 



It must not be suppcsed from these remarks that coal- 

 tar ca mot be used o^i the plum or other trees of its 

 class. On the contrary, there is no suljstauce which can 

 replace it in the treatment of large wounds on these trees, 

 but it sht'uld be used cautiously, especially in the case of 

 youug trei s, and should not be allowed to needlessly run 

 down ihe truuk; ami it is well to remember that the more 

 active a remedy, the greater the care nectfssary in its 

 appUc:diou. 



The practice of leaving a .short stump to an amputated 

 branch, adopted by some persons to prevent the loss of 

 sap, although less objectionable in the case of coniferous 

 trees, should never be a<loptcd. ^'tu:b stumps nmst be cut 

 again the following year c\oy\) to !he trunk, or cushious 

 of wood will form about their b:i.>;e, covering the trunk 

 with protuberances. These greatly injure the appearance 



