TRIMMING — METHOD OF COUNT DES CARS. 95 



On wounds of moderate size, one coat is enough ; but if unusually large, we should 

 be careful to give a new coating at the end of some years, and in the extreme heat of 

 summer it may be rendered so liquid, that it but imperfectly protects a wound to 

 which it may bo then applied. To make sure of a good result, such work might be 

 gone over with a new coat in winter. 



When this substance is apijlied to the elm, it is not so certain in operation as with 

 other forest trees, such as the oak, ash, sycamore, beech, hornbeam, &c., upon which 

 a single coat gives at once great permanence, and remains as a glistening surface. 

 But on the elm its adhesion is not always complete, and it sometimes raises in blisters, 

 as do paints when applied to a damp wall, and there appears an exudation of reddish, 

 fetid juice. In such cases there is no better remedy than to return after some time, 

 rub oif the non-adhering tar, and apply a new coat. It is to be noticed that the exuda- 

 tion of extravasated and decomposed sap is frequently observed in the elm, without 

 any visible cause. In such cases an opening should be made to the bottom of the 

 diseased part, which occasions the abundant flow, and repeated applications of coal- 

 tar will then often work a cure. A similar practice applied to oaks affected by frost- 

 cracks will produce equally good results. 



Coal-tar may likewise be used with good effect in preserving trees from the teeth of 

 lesser rodents, as well as from sheep, goats, horses, &o., which show preference for 

 certain kinds, such as the elm and poplar ; but it should not be used indiscriminately, 

 for, besides the danger of suffocation in a tree thus covered, we should remember that 

 this material contains a, powerful acid, which might decompose the sap. We should 

 g,lso use it with caution on stone-fruit trees — the plum, for example — and on nut-trees, 

 in which the bark appears to have been sometimes altered by contact with it ; but in 

 fruits having a core, such results are not observed, and it may be employed without 

 reserve. The author under notice comes to the following conclusions concerning coal- 

 tfir: 



"From these facts we are not to infer that I proscribe the use of coal-tar upon 

 stone-fruit trees any more than upon the elm ; on the contrary, I know of no other 

 substance which can take its place for the preservation of wood and the healing of 

 large wounds ; but when we come to treat young trees of this class, wo should not 

 daub them coarsely, so as to cover the trunk at ha^^ard or leave it to flow carelessly 

 down the bark, for then it will be liable to produce diseased places. The more active 

 the remedy is, the more caution we should observe in using it." 



In the trimming of the " white woods " (such as the poplars, birches, lindens, &c., 

 so called to distinguish them from the "hard woods," such ns oak, elm, beech, and ash), 

 and in the treatment of conifers, our author remarks as follows : 



" The white woods, being softer and more easy to work, are adapted to many valua- 

 ble uses. Their rate of growth being three or four times greater than in the hard 

 woods, they present special advantages for cultivation. 



" The Poplars, thanks to their rapid growth and to the excellent quality of their 

 wood, form a group of especial interest. The utility of trimming in their case no one 

 will deny, and their management is precisely like that of other trees. They thrive in 

 almost every kind of soil, but prefer the soft and moist for yielding the largest prod- 

 uct. They therefore thrive admirably in valleys and along ditches of drainage. The 

 soil thrown out in cleaning these ditches, if not too much at a time, gives them a 

 remarkable tendency to sprout and send out roots from which new stems spring up, 

 thus availing themselves of the abundance which would kill off other kinds. They 

 eometimes grow to colossal size. The finest species that we have in France is the 

 white poplar, and its wood has so many choice qualities, that it has received the name 

 of " the oak of white woods." Such is their vigor of growth, that we may without trouble 

 lengthen their trunks so as to greatly increase their industrial value, i. e., we may make 

 this part from one-half to two-thirds of the total height. The formation of their 

 branches and the moderate strength of the wood, in fact, makes it necessary to shorten 

 them to prevent the winds and frosts from breaking them, at a great loss. 



One species, the Italian poplar, is perhaps the only tree that requires to be treated 

 according to the old method of trimming the heads, by cutting at modtrately-frequent 

 periods all the branches except a clumi) at the top. The trunk, thus managed, takes 

 an almost cylindiical form, and takes a much longer growth than when the middle 

 and lower branches had been sf;vtrd. In fact, all the branches of this poplar take a 

 vertical direction, and consequently become almost as large as the trunk itself, which 

 greatly adds to their value. Thus, an Italian poplar 20 meters high would have a 

 trunk of 10 to 12 meters; but trimmed according (o the above rule, it might be carried 

 up so as to give 15 meters or more of a size proper for working. But, on the other 

 hand, this kind of poplar will not acquire that majestic port for which it is admired 

 unless left to itself till grown to its full size. 



" The resinous or coniferous trees ^jenerally grow in masses, forming beautiful forests, as 

 in the case of pines and firs, and alford a most precious resource for reboisement,' as 



'The use of this word from the French (signifying ''^ replanting with trees H) has 

 been sanctioned by use of English writers, and it will be adopted in this report without 

 further explanation. 



