Why Fall Planting is Good - By Prof. J. c. whitten 



University of 

 j Missouri 



TREES DO BETTER IF ROOTS GROW BEFORE TOPS, AND IN THE FALL NEW ROOTS FORM 

 QUICKER THAN IN SPRING-WHAT MAY BE SAFELY PLANTED AND WHAT MAY NOT 



SPHERE is hardly a month in the 

 year which some one somewhere 

 has not suggested as a good time for trans- 

 planting trees. The consensus of opinion, 

 however, is that deciduous trees and shrubs 

 ought to be transplanted during the dor- 

 mant period after the leaves shed in the 

 fall and before they come out in the spring. 

 There is quite a difference of opinion as 

 to whether fall planting or spring planting 

 is better, while some even advise for large 

 trees to transplant in mid-winter. 



Observations during recent years have 

 convinced me that fall planting is best 

 for all ordinary hardy species; that spring 

 planting is preferable for most species 

 which are tender or liable to winter-kill 

 and that for very large trees or shrubs 

 which are to be moved, mid-winter is a 

 good time in which to do it. The reason 

 for choosing mid-winter for large speci- 

 mens is that the earth will hold about 

 their roots when frozen so that their 

 large root system can be moved undisturbed 

 with the tree. 



Trees or shrubs transplanted in the early 

 fall make good root growth quickly and 

 become pretty well established before 

 winter comes on. In fact, it has been 

 observed that where spring-transplanted 

 trees do not begin root growth until warm 

 weather is well advanced, trees transplanted 

 in the fall quickly begin to make new root 

 growth. Furthermore, this continues much 

 later in the fall than has heretofore been 

 generally supposed. It keeps up until the 

 ground actually freezes below the roots. 

 So long as the roots extend below the frost 

 line, growth and repair of transplanted 

 roots apparently can continue even into 

 early winter. Just why this root growth 

 in a dormant tree goes on with such avid- 

 ity in autumn may not entirely be under- 

 stood. 



HEAT IN THE SOIL 



The soil contains its greatest amount 

 of heat in autumn about the time fall 

 transplanting begins. It continues to ab- 

 sorb heat and store it up to a greater and 

 greater depth throughout the warm part 

 of the year. It does not reach its greatest 

 sum total of heat at the time of the warmest 

 atmospheric temperatures in mid-summer 

 but continues to store heat deeper and 

 deeper until cold weather of autumn act- 

 ally begins. For this reason we have in 

 the soil in autumn a great quantity of 

 heat stored to its maximum depth. In 

 fact, at this time the heat has reached its 

 greatest depth. Upon the approach of 

 cold weather in late autumn this heat be- 

 gins to be exhausted from the soil. The 

 passing out of this heat with the cooling 

 of the soil during late autumn and early 

 winter no doubt supplies to the roots of 



the tree warmth which is akin to the mild 

 bottom heat of the hotbed. The cool 

 atmosphere of autumn will hold the buds 

 of shrubs and trees entirely dormant, 

 while the heat coming out of the soil stim- 

 ulates by its gentle influence continued 

 autumn root growth. Observations on 

 autumn planted fruit trees as well as orna- 

 mentals, show that during this autumn 

 period the root growth of recently trans- 

 planted trees and shrubs is abundant and 

 continues until the soil literally freezes. 



THE CONDITION OF THE TREE 



Trees and shrubs make their most rapid 

 growth during very early spring. In this 

 climate (Missouri) the average tree or 

 shrub puts out more length growth during 

 May than during all the rest of the growing 

 season combined. Stored plant food and 

 energy in the tree apparently is being used 

 to make mere length growth in early spring. 

 During the remainder of the year a dif- 

 ferent kind of growth continues — that of 

 filling up the new twigs, thickening the 

 cell walls and storing the plant with 

 abundant reserve supply of plant food. 



In the late season this stored food ap- 

 parently is available to be carried to any 

 point where repair is needed, such as the 

 healing of wounds or the making of new 

 roots on transplanted trees. If a limb is 

 cut off in very early spring not much 

 healing will be observed as long as rapid 

 length growth of spring continues. The 

 tree's food supply and energy are going 

 to make new length of limb. If a branch 

 is cut off later in the season after length 

 growth stops, new tissue will quickly push 

 out and begin to cover the wound. Ap- 

 parently throughout the late season the 

 tree is filled with reserve supply of food 

 to be used wherever thickening, healing of 

 wounds, or making of roots is needed. 

 This may be also an additional reason why 

 root growth continues so much more rapidly 

 in autumn than in spring. 



SPRING PLANTING CONDITIONS 



In early spring the soil contains its 

 smallest sum total of heat. The heat 

 stored up during the previous summer has 

 been lost or radiated from the soil during 

 the winter. The soil is usually wet in 

 spring and the presence of this water 

 requires a great quantity of heat to warm 

 it up. The atmosphere is warming rapidly 

 while the soil is warming but slowly. As a 

 result top growth above ground is stimu- 

 lated. The buds start out and this rapid 

 length growth is calling for stored food 

 supply in the tree. Apparently the stored 

 food and energy are directed to the grow- 

 ing tips above rather than to the roots 

 below. Root growth is slow and uncertain. 



Frequently in this section young trees 



106 



transplanted in spring come out in full 

 leaf before any visible starting of root 

 growth below ground can be observed. 

 Under average spring conditions I have 

 taken up, each week, spring-transplanted 

 trees and shrubs without finding any 

 visible new root growth beginning until 

 June after the tops of the trees had 

 for weeks been in full leaf. With the 

 warming of the soil in June new roots began 

 to form. If the season is favorable the 

 trees may make fairly satisfactory growth. 

 If a dry time comes on in early summer, 

 the trees will likely fail or even die. 



The tree which is out in full leaf long 

 before any roots begin to form is then in a 

 dangerous condition. Any sudden call 

 for moisture such as prevails during an 

 early dry spell may find the leaves of the 

 transplanted trees evaporating more water 

 than the unrepaired root system can take 

 up. Frequently spring-transplanted fruit 

 or shade trees start out in leaf beautifully 

 and the owner thinks they are firmly and 

 permanently established, without realizing 

 that perhaps the roots have not begun to 

 grow a bit below ground. As a result, 

 if dry weather suddenly comes, trees which 

 during May were very promising, dry out 

 and die during June or July. 



Again new root growth is essential to 

 anchor the tree firmly in the ground. A 

 tree cannot well resist strong winds until 

 new roots have taken hold of the soil and 

 fastened themselves by their new growth. 

 For that reason, spring-transplanted trees 

 presenting abundant leaf growth may 

 catch more wind above ground than their 

 retarded roots can support and hold. 

 Tipping or leaning of spring-transplanted 

 trees is much more usual than is the case 

 with autumn-transplanted trees. 



TIME TO TRANSPLANT IN AUTUMN 



The best time in autumn for transplant- 

 ing is just when the bulk of the leaves 

 are shed from the plant and yet before it 

 reaches entirely its dormant state. It is 

 customary for some nurserymen to strip 

 green leaves from their trees in early 

 autumn in order to supply them for early 

 fall delivery. This is largely on account 

 of the demand of the planter who wants 

 his trees and shrubs delivered promptly 

 for fall setting. Stripping the leaves early 

 from the trees is undesirable. They should 

 remain on the trees until they have finished 

 their summer's work and are ready to 

 fall naturally. On young trees or shrubs, 

 however, the leaves are tardy about 

 falling. If growth has continued late, 

 they may cling until cold weather. There 

 is a time, however, when mature trees 

 or shrubs of the same species are shedding 

 the bulk of their leaves when it will be 

 found that leaves pull very easily from the 



