Dwarf Fruit Trees

<h2><SPAN name="IV" id="IV"></SPAN>IV</h2> <h3>PRUNING DWARF FRUIT TREES</h3> <p>The pruning of dwarf fruit trees is a matter of the greatest consequence, for on proper pruning depend both the form and the productivity of the trees. Some of the details of management will be explained in the succeeding chapters, dealing with the particular kinds of fruits, but a few general statements should be set down here.</p> <p>1. The trees are severely headed in. This applies more particularly to bush and pyramid forms. By the term "heading in" we refer to the shortening of the leaders. Such shortening is usually given at the spring pruning, while the trees are dormant. The leaders may be headed in at times, however, during the latter part of the growing season, in July. Such stopping of growing leaders will be practised more often on young trees just coming into bearing than on old trees. (Fig. 10). Constant heading back of some sort, however, is required in nearly all cases, if the tree is to be retained in its dwarf form. The mistake has often been made of thinking that a tree propagated on a dwarf root would take care of itself.</p> <p>2. Summer pruning is essential. In most American orchard practise one annual pruning (sometimes one pruning every five years!) is considered sufficient, and systematic summer pruning is seldom or never given. Now summer pruning tends much more to repress the growth of a tree than winter<span class="pagenum"><SPAN name="Page_35" id="Page_35">[Pg 35]</SPAN></span> pruning does. In fact, heavy winter pruning leads rather to increased vegetative vigor. Aside from any special system of pruning, therefore, this rule is to be remembered, that summer pruning is desirable, on general principles, for dwarf fruit trees.</p> <div class="figcenter"><SPAN name="i0046" name="i0046"></SPAN><div class="figborder"> <ANTIMG src="images/i0046.jpg" alt="" /> <p class="caption">FIG. 10&mdash;BUSH APPLE, THREE YEARS OLD</p> <p class="ctext">Showing strong leaders formed during the summer</p> </div> </div> <p>3. Side shoots usually need pinching during the growing season. Leaders are more frequently allowed to grow unchecked throughout the season, or are stopped only late in their period of development. In the pomaceous fruits, which form distinct fruit spurs, the checking of these side shoots helps toward the production of fruit buds. As long as every bud is allowed to push out into a strong shoot no fruit spurs can become established. Thus the summer pinching of the side shoots on apples and pears has the purpose of encouraging the formation of fruit spurs. On peach and plum trees equally distinct fruit spurs do not form; but if the side shoots are allowed to push forth unrestricted they are apt to choke one another. There will be too many of them, they will not get light enough, their growth will be weak and sappy, and they will not form fruit buds. Good fruit buds on a peach tree, for example, form on strong, clean, healthy shoots of this year's growth for next year's crop of fruit. It is seen, therefore, that in nearly all sorts of dwarf fruit trees the summer pruning is especially directed to the suppression or regulation of the growth of side shoots.</p> <p>This part of the treatment becomes of prime importance in dealing with cordons and espaliers.</p> <p>4. The control of the fruit spurs or of the side shoots here contemplated requires that the trees be gone over more than once during the growing season.<span class="pagenum"><SPAN name="Page_36" id="Page_36">[Pg 36]</SPAN></span> In fact, four successive examinations of the tree are usually required. Old trees can sometimes be managed with two or three, but young ones, on the other hand, will sometimes require six or more. Of course, there are usually only a few shoots that need attention at each succeeding visit, and the work can be very rapidly performed. The first pruning, or pinching, falls about three weeks after the trees have started into growth. The next one comes ten days later, the next one ten days later again, and the fourth pruning two weeks after the third. From this time onward the intervals lengthen. These specifications, of course, are only approximate and suggestive. Some judgment is required to select just the proper moment for pinching back a shoot and even more to select the time for a general summer pruning. Those trees which enjoy the sympathetic presence of the gardener every day are sure to fare best. The bulk of this pruning can be done with the thumb nail and forefinger, but I find a light pair of pruning scissors pleasanter to work with.</p> <p>5. Root pruning is sometimes advisable. Since the whole program is arranged to check the growth of the dwarf tree, root pruning would naturally fit well with the other practises recommended. Root pruning checks the growth of a tree about as positively as any treatment that can be devised. When dwarf pear or apple trees seem to be making too much wood growth and not enough fruit, they can be taken up, as for transplanting, during the dormant season and set right back into place. This digging up and replanting is always accompanied by some cutting of<span class="pagenum"><SPAN name="Page_38" id="Page_38">[Pg 38]</SPAN></span> roots. The whole root system is disturbed and has to re-establish itself before the top vegetates very strongly once more. Such root pruning ought to be done late in the fall. It is a special practice, suited to refractory cases, and the gardener is not recommended to indulge in it too freely.</p> <div class="figborder2"> <table summary="image"> <tr> <td class="tdlp"><div class="figcenter"><SPAN name="i0049a" name="i0049a"></SPAN> <ANTIMG src="images/i0049a.jpg" alt="" /></div> </td> <td class="tdrp"><div class="figcenter"><SPAN name="i0049b" name="i0049b"></SPAN> <ANTIMG src="images/i0049b.jpg" alt="" /></div> </td> </tr> <tr> <td class="tdlp"> <p class="caption">FIG. 11&mdash;BUSH APPLE</p> <p class="ctext">Three years old, before pruning</p> </td> <td> <p class="caption">FIG. 12&mdash;BUSH APPLE</p> <p class="ctext">Same tree after pruning</p> </td> </tr> </table></div> <p>6. A certain equilibrium between vegetative growth and fruit bearing should be established at the earliest possible moment, and should be maintained thereafter. Of course, some such equilibrium is sought in the management of a standard tree; but it is secured earlier in the life of the dwarf tree and should be much more accurately maintained. The tree must make a certain amount of growth each year, but this must be only enough to keep it in good health, and to furnish foliage enough to mature the fruit. Beyond this wood growth the tree should bear a certain amount of fruit every year, for annual bearing is not only an ideal but a rule in the management of dwarf trees. This equilibrium once established must be maintained not by haphazard pruning, but by some suitable system. If there is the proper balance between summer pruning and winter pruning, combined with proper control of cultivation and fertilization, then the balance between vegetation and fruitage can be kept up. It is a delicate business, like courting two girls at once, but it can be carried out successfully.</p> <p>7. The training of trees into mathematical forms is largely a mechanical process. For the most part the trees are shaped while they are growing. The young shoots are twisted and bent to the desired positions, and are tied into place until the stems become<span class="pagenum"><SPAN name="Page_40" id="Page_40">[Pg 40]</SPAN></span> hardened. There are many clever little tricks for expediting this sort of work and for making the results more sure, but a rehearsal of them here would be tedious. The most important rule to remember is that constant attention must be given the shoots while they are growing. Mistakes are corrected with difficulty after an undesirable form has been allowed to harden.</p> <div class="figborder2"> <table summary="image"> <tr> <td class="tdlp"><div class="figcenter"><SPAN name="i0051a" name="i0051a"></SPAN> <ANTIMG src="images/i0051a.jpg" alt="" /></div> </td> <td class="tdrp"><div class="figcenter"><SPAN name="i0051b" name="i0051b"></SPAN> <ANTIMG src="images/i0051b.jpg" alt="" /></div> </td> </tr> <tr> <td class="tdlp"> <p class="caption">FIG. 13&mdash;CORDON PEARS</p> <p class="ctext">Before pruning</p> </td> <td> <p class="caption">FIG. 14&mdash;CORDON PEARS</p> <p class="ctext">After pruning</p> </td> </tr> </table></div> <hr style="width: 65%;" /><p><span class="pagenum"><SPAN name="Page_41" id="Page_41">[Pg 41]</SPAN></span></p> <div style="break-after:column;"></div><br />