184 
THE FLORIST AND POMOLOGHST. 
[ August, 
shifted about from place to place, and are ventilated with great facility. Early in 
the season air is given at either end of the case by slipping a pane outwards ; later 
on, the box is tilted by means of half a brick or a block of wood ; as the season 
further advances, one or two panes are taken out altogether, and the remaining 
panes placed at regular intervals, leaving spaces between each pane for air, which 
air remains on night and day. They cause very little labour, and are not liable 
to breakage. After the beginning of May the plants under them require plenty 
of water, which can be easily applied by tilting the box, so as to allow the spout 
of the water-pot to enter at the ground-level. The uses to which cases of this 
kind can be put are both obvious and multifarious. Mr. Eendle, we understand, 
regards this form of Protector as an infringement of his patent.— T. M. 
ON ARRESTING THE GROWTH OF LARGE TREES 
BY DENUDING THEIR ROOT-BASE. 
>0 part of the organization of a tree is more delicately sensitive than the 
apparently rough and sturdy masses formed by the main root-limbs 
where they diverge from the central axis. Life is here most full of vigour, 
and highly responsive to every variation of heat, cold, drought, evaporation, 
nay, of light itself. It happens, not unfrequently, that some fine half-grown tree 
upon a lawn or foreground, is threatening soon to become inconveniently high and 
large for its place; and the owner is ever bewailing the vigour and rapid growth that 
must soon condemn it to the axe ; even a whole line, or double line of trees, may be 
on the point of out-growing their proper size in reference to surrounding objects. 
Now, we cannot have recourse to root-pruning in the case of a half-grown forest 
tree, for it would not only be costly, but exceedingly uncertain in its effects. If, 
however, we apply a check to the sensitive surface of the main roots, just where 
they part from the central axis at the bottom of the stem, and admit air, light, 
heat, cold, and evaporation there, by removing turf and soil,—perhaps but a 
single barrowful,—we shall soon perceive very remarkable effects. No unsightly 
weakness of foliage will be visible the following summer, but the terminal shoots 
will be more or less shortened and arrested, and they will prepare themselves for 
forming flower-buds to be developed in the next ensuing spring. 
If we look a few months later, at the root-limbs thus laid bare, we shall be 
struck by their visible enlargement from fresh deposit of bark and woody matter 
over the exposed surface. The great plant, whose economy we had disarranged 
by taking away but a few spadefuls of earth and herbage, has applied itself first 
and foremost to make good that loss, and to guard its most important central 
organism from evaporation and sudden alternations of temperature, by depositing 
a fresh layer of bark and alburnum, of more than ordinary thickness, upon the 
main root-space. To do this, it has transferred its vegetative energies from the 
upper spray, and bestowed them on more needful work below. Such is the 
wonderful providence which guides arboreal vegetation. When summer again 
comes round, flower and seed will probably be found upon the tree, even if it 
