THE GARDENERS' CHRONICLE OF AMERICA. 
405 
DYNAMITE FOR SOILS 
A QUARTER of a century ago, a fruit grower in 
California, in digging holes for some fruit trees, 
came upon hardpan which was nearly as tenacious 
as cement. He used some dynamite with which 
to break up the hardpan in order to get the holes 
deep enough to plant the trees at a right depth. It was 
discovered that the trees planted in the dynamited 
holes made a much larger growth, and better withstood 
the dry weather that followed. From this discovery 
a general interest has grown in tin's method of pre- 
paring the soil for trees. 
While there are many instances where soil condi- 
tions have been improved by the use of dynamite, this 
does not follow with all soils, and it thus becomes im- 
portant to know and to understand the distinctions. 
In a soil that contains 65 per cent, claw with a yellow 
Dynamiting Increases the Productiveness of Most Soils. This 
Splendid Crop of Potatoes Was Grozmi Where 
Dynamite Was Used in Subsoiling. 
clay loam subsoil, one-half a stick of 20 per cent, dyna- 
mite put down two and a half feet will loosen the top 
soil for six feet around and five feet deep. The 20 per 
cent, strength is better than 40 per cent., as the slower 
explosive leaves the soil in better condition. 
Dynamite, however, should not be regarded as a 
digger of holes for planting trees, as a properly placed 
tree planting charge sin mid be tamped in to insure the 
maximum breaking effect of the subsoil, and this 
tamping prevents the excavation of a hole for planting 
the tree, but the shock of the blast makes excavating 
with a shovel easy. 
It is important to follow this plan in setting out 
trees. After the blast, shovel out the top soil and set 
it to one side, then shovel out the subsoil until the 
point where the dynamite cartridge was exploded is 
reached. As a rule a cavity will be found one to two 
feet in diameter; it is important that this be filled with 
subsoil. If the tree is planted without doing this, the 
subsoil will gradually drop down into the hole, leaving 
the tree roots suspended in the air, when the tree will 
die. Haying filled the cavity, subsoil should be shov- 
eled in to a point just below where it is desired t<> 
place the roots of the tree. Then put in half of the 
top soil. Lay the roots on this top soil in their natural 
position and cover them with the remaining top soil 
and pack it in firmly by treading it with the feet. Then 
till the remainder of the hole with subsoil. 
Several effects are produced that benefit the trees 
planted in soil so treated. Excellent and quick drain- 
age is provided for the roots, which is essential to their 
health and vigorous growth. A heavy, soggy or over- 
wet subsoil will retard the growth and bearing of 
trees by several years, as many of the fine feeding- 
roots will perish when confined for several weeks in 
such soil. The breaking up and loosening of a heavy 
subsoil may be done much more effectively through 
the use of dynamite than is possible by digging holes 
three feet in diameter and fifteen inches deep with a 
pick and spade, as is usually done. 
The subsoil should be dry at the time of the blast- 
ing, otherwise the effect is detrimental rather than 
beneficial, as a blast in wet subsoil throws the dirt 
high in the air and plasters it against the sides of the 
hole, failing to crack the subsoil as it should, several 
feet around the hole. 
If the planting is done in the spring, it is necessary 
to wait until the subsoil is reasonably dry. Trees 
properly planted with dynamite will not die, but will 
grow rapidly right through the dry summer, and will 
bear fruit one to two years earlier than trees planted 
with a spade. 
The next important benefit that follows from the 
use of dynamite is the more thorough aeration of the 
soil that is produced. An abundance of air in the soil 
is highly essential to plants. 
The roots of trees perform the necessary function 
of taking up plant food that must first be made sol- 
uble, when through the circulation of sap it is util- 
ized in making new layers of wood, foliage, fruit buds 
and fruit. The oxygen in the air performs an impor- 
tant part in the processes going on, and in the changes 
which take place in the chemical constituents that are 
present in every grain or atom of soil, and which are 
necessary for the growth of all vegetation. 
Where the soil is heavy, and in poor physical con- 
dition, trees are more subject to diseases that not only 
retard their growth, but to a certain degree make 
them unfruitful. Therefore, the better the soil is pre- 
pared by making it more open or porous, and capable 
of taking in the air freely and abundantly, the greater 
will be the degree of health, vigor, growth and pro- 
ductiveness. 
Where the subsoil is of an open or porous character, 
with a sandy loam top soil, the use of dynamite is not 
advisable, for such subsoil should not be broken. The 
foundation will become too loose or soft. The drain- 
age will be made too excessive ; the subsoil moisture 
will not be so usable or effective in its upward move- 
ment, because its medium has been broken up and 
changed, in consequence of which the trees will suf- 
fer severely in times of prolonged drought, and during 
heavv windstorms they will be blown over, for their 
roots will not be held by a sufficiently firm soil. 
The use of dynamite is practical and economical. 
