4 Forms, of Trees. [zoe 



which durine the whiter season are void of leaves. In some horti- 

 cultural districts, where snow but seldom falls, and where accord- 

 ingly such trees as olives, oranges and lemons are cultivated suc- 

 cessfully, an occasional fall of snow may do and has in many in- 

 stances done considerable harm. We know that when the snow 

 lodges on the evergreen and upright limbs of orange trees, these 

 limbs become so heavy that they break down, more or less ruining 

 the trees. On such occasions the growers hurry through their 

 orchards shaking off the snow before it begins to melt and become 

 heavy, thus freeing the limbs of the trees from the burden that 

 would injure them. The cause of the mischief is thus not alone 

 to be found in the snow, but also in the upright shape of the limbs 

 and trunks of the trees. Those limbs which point upwards do not 

 yield readily under the pressure of the snow, and trunks which 

 are repeatedly forked, will, if the pressure is heavy enough, split 

 lengthwise. In case the trees in question had possessed downward 

 sloping limbs and an upright, undivided or standard trunk, the 

 effect of the snow pressure would have been less dangerous; the 

 Ijmbs would have yielded to their snow burden, which^when melt- 

 ing, would have slipped off, leaving the limbs free, and the undivided 

 trunks would not have split, and the trees would have escaped with- 

 out injury. If such snowfalls were frequent and regular, only sucii 

 varieties could be cultivated as were possessed of downward slop- 

 ing limbs and upright trunks. All trees shaped otherwise would 

 gradually be ruined and their cultivation become impossible. These 

 last remarks refer only, or at least principally, to evergreen trees. 

 If the orange trees, which we gave as an example, instead of being 

 evergreens were deciduous, that is, presenting only bare limbs ia 

 the winter, like peaches, apricots and pears, the pressure of the 

 snow would not have injured them, at least not by breaking their 

 limbs and splitting their trunks, and their cultivation would not 

 necessarily have been abandoned. If we consider a forest, instead 

 of a horticultural district, we will find that the conditions are there 

 very much the same. The yearly snowfall, if only heavy enough, 

 tends to break down and destroy all wild evergreen trees, which do 

 not possess a form suitable to resist the heavy snow mantle. Trees, 

 which would thus suffer would be all evergreen trees with spread- 

 ing crowns, such as live oaks, laurels, madroiia, certain pines, such 

 as Monterey pine, digger pine ( Pimis Sabmia7ia) , Italian pine ( Pinus. 



