February 24 1897.] 



Garden and Forest. 



7 1 



GARDEN AND FOREST. 



PUBLISHED WEEKLY BY 



THE GARDEN AND FOREST PUBLISHING CO. 



Office: Tribune Building, New York. 



Conducted by Professor C. S. Sargent. 



ENTERED AS SECOND-CLASS MATTER AT THE POST-OFFICE AT NEW YORK, N. V. 



NEW YORK, WEDNESDAY, FEBRUARY 24, 1897. 



TABLE OF CONTENTS. 



PAGE. 



Editorial Article : — Tree Pruning 71 



The Chemist: World Carl Purdy, 72 



Leaf-spot of Pear George F. Atkinson. 73 



Foreign Correspondence: — London Letter IV. Watson. 74 



New or Little-known Plants: — Hoodia. (With figure) W. Watson. 76 



Cultural Department: — Lachenalias E. O. Orfet. 76 



Select Dwarf Stove Plants William Scott. 77 



Stag-horn Ferns G. W Oliver. 77 



Hardy Cyclamens J. N. Gerard. 78 



Propagating Chrysanthemums T. D. Hatfield. 78 



Correspondence : — Notes from Wellesley IV. N. Craig. 7S 



R ecent Publications 79 



Notes So 



Illustration: — Hoodia Gordoni, Fig. 10 75 



Tree Pruning. 



TREES can still be pruned to advantage up to the 

 time, now rapidly approaching, when the limbs 

 are gorged with sap, so that they will bleed more plenti- 

 fully than at other seasons. This loss of fluids does not 

 operate to weaken the vitality of a tree to any serious 

 extent, but as the sap runs down the bark and keeps it wet 

 for a long time, besides preventing the adhesion of any 

 coating over the raw surface, the spores of various rot 

 fungi are apt to find a lodgment in the wound so 

 that decay will set in. This loss of sap will make com- 

 paratively little difference in the case of small limbs, and 

 it should not prevent the prompt removal of stem and root 

 sprouts, for example, so that these will not continue to ex- 

 haust the energies of the tree another season. As a rule, late 

 autumn is the best season for the general pruning of orna- 

 mental trees, because the leaves are then out of the way 

 and the branches which cross and rub against each other 

 can be detected. When the whole skeleton is made bare 

 it is more easy to see which branch it is that projects in 

 such a way as to make an unsymmetrical head and where 

 the limbs are growing too thickly. 



Of course, no one should be allowed to use a knife or a 

 saw on a tree unless he knows exactly what he wants to 

 accomplish by pruning and can tell why the operation will 

 bring about the desired end. Some tree lovers are so sen- 

 timental that they look upon any pruning whatever as a 

 species of cruelty. Others believe that every effort to make 

 a tree shapely is unnatural, and therefore inartistic. But it 

 can be easily demonstrated to the first class that, instead of 

 inflicting an injury, the good pruner can add to the vigor 

 and longevity of a tree, especially of one which for any 

 reason has begun to show signs of feebleness. To the 

 other class it may be said that the effort to keep the tree 

 shapely and in its proper natural balance by pruning is 

 quite a different operation from clipping it into a form 

 unlike what it ever would assume if naturally grown. It 

 is small wonder that persons who watch a gang of profes- 

 sional tree-trimmers moving their equipment of ladders 

 and axes from one tree to another along a city street 



shudder at the butchery they witness. These impostors 

 often saw off every large limb a few feet from the trunk and 

 leave only an occasional stub projecting from the remnants 

 of these limbs, so that what was once a tree becomes a 

 mutilated stump, and the very process which was intended 

 to make it healthy and beautiful ruins it beyond any hope 

 of recovery. Of course, street trees need pruning, but if 

 they have been well selected at the outset a small knife 

 will suffice to remove while they are young an occasional 

 branch which starts from the wrong place, and if they are 

 carefully attended to for some years rarely will any large 

 branches need to be removed. While on the subject of 

 shaping trees it may be remarked that on a broad lawn 

 single trees never look as well as when their branches 

 sweep the turf, and in most instances it is a barbarity to 

 cut these away. Coniferous trees which grow in a pyra- 

 midal form, unless they are closely crowded in a wood, 

 always branch close to the ground, and the removal of 

 these lower limbs not only converts a beautiful tree into 

 an unsightly object, but it almost certainly injures the 

 health of such species as naturally grow in moist climates, 

 for these low branches not only check evaporation from 

 the soil and retain moisture about the roots of the tree, but 

 they help to bring the centre of gravity of the mass nearer 

 the base, and in this way enable the tree to better with- 

 stand the force of the wind. 



We began this article, however, for the special purpose 

 of calling attention to the fact that pruning can be used as 

 a remedial or restoring process upon deciduous trees which 

 have become decrepit. There is nothing new in this, and 

 in the very first volume of this journal, and often since then, 

 we have explained how trees which have begun to show 

 signs of enfeebling age can have their youthful vigor 

 renewed. When the upper branches of a tree begin to 

 die, this means that for some cause the tree is receiving 

 insufficient nourishment. When the ground has been 

 pastured over and trampled upon, the food taken away 

 by grass or crops and the tree neglected in every way, 

 there is nothing that will so stimulate new life as vigorous 

 surgery. More is needed than the cutting away of branches 

 already dead. A tree on the decline should have its main 

 branches all shortened in from one-third to one-half their 

 length. What is needed is more leaf-surface, because the 

 vital work of the tree is carried on in the leaves, where the 

 plant food taken up by the roots and from the air is elabo- 

 rated and transformed into growing tissue. These feeble 

 branches carry nothing but small and scattered leaves 

 which do not suffice to carry on the life-work of the tree 

 with energy. But when a branch is cut away the tree at 

 once exerts itself to throw out new shoots, and these shoots 

 will bear much larger leaves, so that the leaf-surface of the 

 tree will be greatly enlarged, while the amount of wood 

 to be vitalized is decreased. Of course, such trees can be 

 helped in other ways — that is, by covering the ground with 

 ashes or well-rotted manure, or by giving in any other 

 way a supply of food that is easily assimilated, but 

 the pruning is the energizing factor in the process. Every 

 one has noticed hovv vigorously a shoot will start from 

 the root of a young Oak which is cut to the ground, 

 and how the leaves will expand to accommodate them- 

 selves to the greater work imposed upon them, and prepare 

 to utilize all the sap the roots will furnish. It is this same 

 principle which will stimulate an old tree when its branches 

 are pruned hard back to throw out new shoots and clothe 

 them with abundant foliage. 



We almost hesitate about repeating such an elementary 

 injunction as that a branch should be cut off close beyond 

 a healthy lateral, and yet it is a rule that we see violated 

 every day, not only in ornamental plantations, but even in 

 orchards. This lateral branch in spring will throw out a 

 great number of leaves which supply themselves with sap 

 which they can digest and send back to the very extremity 

 of the amputated limb. If this extremity is painted over 

 with coal-tar, or any other thick paint laid on with a brush, 

 the wound will besrin to heal over at once. On the con- 



