934 
IShe RURAL NEW-YORKER 
that goes down into the gi'oxind below the frost line, 
'i'he floor .should l)e of concrete, and should slope to 
a drain in the center. The outlet of the drain pipe 
sliould be located so one can got at it. At filling 
lime the drain may be stopped up with a wooden 
plug. If there is an excess of water in the silage so 
it leaks out around the lower door this excess mois¬ 
ture can be let off through the drain. A chute should 
lx. built over the doors so the silage can be thrown 
into a truck easily. 
SIZE OF SILO.—In general the height of the silo 
should not be more than three times or less than 
twice the diameter. A cubic foot of silage weighs 
OTi an average 40 lbs. An average amount of silage 
to feed a Holstein cow is 40 lbs. a day, for other 
ftreeds .'!0 lbs. a day. The yield per acre depends on 
the kind of corn, the method of seeding and the 
maturity of the crop. 15 tons per acre is a fair 
average. Knowing these factors we can with the aid 
of the following table find the proper diameter and 
height to build our silo. 
a'ATil.E I. 
Capacity of silo having an inside diameter. 
10 
11 
12 
1.3 
14 
15 
19 
17 
18 
20 
ft. 
ft. 
ft. 
ft. 
ft. 
ft. 
ft. 
ft. 
ft. 
ft. 
Depth of 
silage after 
settling tAvo day 
'S. 
Feet. 
Tons. 
24 
2t: 
38 
40 
55 
, , 
* , 
• • 
2S 
42 
51 
91 
71 
S3 
.39 
47 
59 
97 
79 
91 
105 
02 
74 
89 
100 
115 
1.31 
34 
80 
94 
109 
129 
14.3 
191 
, , 
.39 
87 
102 
119 
1.39 
155 
175 
199 
, , 
110 
128 
147 
197 
1.89 
212 
291 
40 
1.58 
l.SO 
20.3 
22.8 
2.81 
42 
170 
19.3 
218 
245 
.302 
44 
« • 
207 
2.‘H 
292 
.323 
49 
2.80 
345 
308 
(Table adapted from King’s Physics of Agriculture, 
P. 424). 
For example, let us suftpose one has a herd of 20 
grade cows. He does not need the silo in ])asture 
season, but will feed silage seven months or 210 days 
at the rate of 00 lbs. per head per day. 
20x 20 = 000 lbs. silage per day. 
000.\210 = 120.000 lbs. silage for 7 months*. 
120.000 2.000 = 02 tons. 
Keferring to the table it can be seen that in order 
to have the height of the silo 2 to .3 times its diam¬ 
eter, 12 feet is the proi>er diameter. Punning down 
this <-olumn it will be noted that a column of silage 
12x2S ft. weighs 01 tons and one 12x.30 ft. 07 tons. 
It is advisable to build the silo a conide of feet 
higher than the figures show to allow for settling. 
And then again it is always well to have a ilttle 
extra room to allow foi* an increase in stock or a 
larger *crop than was estimated. Hence in the above 
case a silo 12x.22 feet would be the pro]»er size. To 
grow the four tons a little better than four acres of 
land woxild be required if the corn yielded 15 tons to 
the acre. Anyone having a silo and wishing to figure 
its capacity can do so by measuring its height and 
width and referring to tlie talde. It may be figured 
closely by calculating the volume of the silo in cubic 
feet and then multiplying this by 40. This will give 
pounds capacity. The volume of a round silo is 
found by finding the area of its base and multi]<lying 
this by its hc-ight. The area of the base is found by 
►(luaring the radius, or in other words, multiplying 
half the dist:ince across the silo by itself. This rc*- 
sult is then multiplied by the factor 3.1410. For ex¬ 
ample, find the capacity of a silo 10x40 feet. 
= 0 ( 4 . 
04x3.1110 = 201.00 area of base. 
201.00x40 - S042.4 cu. ft. Yol. of silo. 
.S042.4x4t) = .321.090. lbs. 
221,090 -f- 2000 = 100 8 tons capacity. 
The table given above is always c-oming in handy, 
and it would be a good plan to clip it out and init it 
where it may be available at any time. 
IWCKING AND FEEDING SILAGE.—The crop 
grown and the silo ready to fill the next essential 
point is to see that the silage is proi»erly packed, par¬ 
ticularly next to the walks. It will spoil to some ex¬ 
tent if the air spaces ai*e left and the man doing the 
tramping must keep on the move. Silage should 
always be fcnl after milking to avoid the milk taking 
on a silage flavor. It is commonly fed before milk¬ 
ing with the grain on toj). For the man making 
market milk for a discriminating trade this practice 
is undoubtedly wrong. Fed after milking there is 
no danger of the milk absorbing the silage flavor. 
The dairyman having a silo full of good silage and 
a barn full of legume hay has done a good bit toward 
helping to win the war, because he will need very 
little of the much-needed high-iiriced grain. P.uild a 
silo. Your cows will appreciate it and you will in 
tuj-n appreciate the better work they will do for you. 
Iowa. II. k. JUPKIKS, 
Soil Temperature and Crop Production 
Pakt II. 
A CASE IN POINT.—I will cite one instance of 
temijerature damage. When growing tomato plants 
in hotbeds in the North, on one or two occa.sions, 
the plants at the center of each sash for some un¬ 
known reason became stunted in growth—from cen¬ 
ter toward the cooler ends and under the shade of 
sash bars. Douhtle.ss the cause was as stated, and 
it was very difficult to induce normal, thrifty growth 
again. The relation between the damage point and 
amount of moisture in the soil is peculiar, and no 
doubt intricate and involved. I have already re¬ 
marked on the benefits of watering in starting a 
seedbed in over-xvarm soil, yet nothing is plainer 
here than that vegetables that are thriving nicely as 
Summer advances under fairly dry soil conditions 
A Hay Cap in Place. Fig. Jf61 
deteriorate very quickly if rainy Aveatlicr sets in. 
After all, is that not in line with midsummer expe¬ 
rience in the North? 
iMOLSTUKE AND HIGH TEMPEltATUKE.— 
Every gardener and farmer dreads a .Summer 
drought, but I believe every thoughtful one will 
agree that any pi'olonged, period of hot, .showery 
weather is nearly as disastrous for most crops, corn 
excepted, and this in spite of the favorable influence 
of cool subsoil. The question arises. Why should a 
generous supply of moisture in the soil abet the 
detriment of too high a temperature? At first 
thought it would ai)i)ear that moisture would coun¬ 
teract .such inlhience by the co(,)ling effects of evapo- 
I'ation; but clearly there is another consideration. 
Is it not ixrssible that acpieous vapors are formed 
so rapidly in a moist, overheated soil as to drive out 
and exclude the air from the soil to such an extent 
\ 
Raking the Scatterings in a Grain Field 
as to practically suffocate the root system? Nor is 
such theory contradicted by the fact that watering 
is beneficial to seed beds. In that case the rootlets 
are in-actically at the surface. Moreover, such Avater- 
ing could be depended on to counteract only a very 
few degrees of damaging tempei-ature. 
DAMAGE FROM MOISTURE.—Am I presuming 
too much when I ,say that most observing farmers 
and gardeners after Avaiting anxiousl.A' for rain 
through periods of drought during ,Tuly and August 
have often been disappointed Avhen rain came to 
find that crops did not respond as expected, AA'ith 
sometimes a lurking suspicion that for some unknoAvn 
rea.son the rain did more harm than good? Po.ssibly 
the following incident may shed light on the situa¬ 
tion. few days ago, talking Avith a friend, recently 
returned from a trucking district at. some distance, 
a circumstance Avas related as folloAvs: The .season 
a])i)earing favorable an acreage of potatoes Avas 
planted later than usual. Some time in euidy June 
August 3, 1918 
the tubers were about half grown and the plants 
in vigorous condition, when a good i*ain occurred. 
The drainage Avas perfect; at any rate, there Avas not 
enough rain to bring the soil anyAvhere near to satu- 
i‘ation. The rain Avas thought to be the making of 
the crop. What happened? The plants, after the 
rain, promptly Avithered and died; not .sloAvly and 
irregularly, as by blight, but promptly and evenly. 
The soil AA’as black muck. The evidence seems com¬ 
plete that the combination of black soil, clear sun¬ 
shine and abundant moisture. Avith little or no re¬ 
serve of coolness in the subsoil, presented ideal con¬ 
ditions for the formation of aqueous A*apor in the 
soil in sufficient quantities to completely suffocate 
the root system of the crop. 3Iay not the same sort of 
injury in modified degree be affecting crops through¬ 
out the country? That brings us to the consideration 
of hoAV much of the benefit of cultivation and mulch¬ 
ing for moisture conservation should really be cred¬ 
ited to benefit from soil temperature control. 
DANtJER FROM LACK OF CULTIVATION.— 
EA’idently the .same means serA'es both puriioses, so 
it may appear Ave might as Avell let it go at that. 
Rut reall.v it is not quite so simple. For instance, a 
gardener finds Avork croAvding. There is an abun¬ 
dance of moisture in the soil, AA'ith shoAA'crs cA'ery 
fe\A' days. Knowing crops are not suffering for 
moisture, he neglects cultivation after shoAvers. Pos¬ 
sibly that cultivation is even more necessary for 
aeration and .soil temperature control. E.specially 
may this be the case in calm, hot, humid Aveather. 
AA'hen he is congratulating himself on losing so little 
moistui-e, Avhile j)ossiblj’ the roots of his ci'ops are 
suff’ociy^ing in aqueous vapor. Surely thi.s phase of 
the subject deserves serious investigation. 
COOLING THE SOIL.—And now, if the theory 
propounded bo true, Avholly or in part. hOAv about the 
practicability of cooling the soil of limited areas for 
garden i)urposes by artificial means, in tropical and 
sub-ti'opical regions, or even for special crops in mid¬ 
summer in temperate regions. The mechanical diffi¬ 
culties in such an enterprise Avould appear .simple 
and inexpensive as compared to greenhouses in the 
North. The greenhouse involves not only expen.sh'e 
protection against the elements in the Avay of struc- 
tui'e and glass, but also heating to counteract many 
degrees of cold. While the cooled .soil area Avould 
])r()bably re(iuire no suijerstructure at all. or at most 
of the simplest and most inexpensive kind, to afford 
.shade a few hours at midday, and the temj)erature of 
the soil AA'ould probably need to be k(‘pt at only about 
10 degrees beloAv noianal, for the Avarme.st parts of 
the Avorld have avei’age temperatures of only about 
81 degree.s. 
A REVOLUTION IN FOOD SUPPLY.—In a small 
AA’ay it .se<Mns the desired tempei-ature might be main¬ 
tained by a .system of underground pipes radiating 
from a large tank of iced Avater. For any consider¬ 
able area refrigeration facilities Avould have to be 
installed. Possibly .such .speculation is idle, hut only 
exhaustiA'e and extensive experiments can proA'e or 
disprove the feasil)ility of the scheme. Should it 
Iirove praclicak it Avould revolutionize the food sup¬ 
ply of the civilized i>opulation of the Avanner jiarts 
of the Avorld. For I remark in passing that fresh 
vegetables, like lettuce, beets, radishes, beans, etc., 
are scarcer, and if to be had at all. higher in iirice 
in Miami, in July, than in Poston in .lanuary. Not 
only that, but Avho can tell but that such vegetables 
as lettuce, for instance. Avhich disappear as a home¬ 
grown article from all the Southern and Central 
mai-kets of our country in midsummer, by such 
means might be groAvn the season through. Certain 
it is that some days in early June, Avhile such crops 
are flourishing, aerial temperatures are as high as 
later, Avhen for some cause such crops fail. 
A CASE FOR EXPERIMENT.—Po.s.sibly the read¬ 
er is di.sposed to criticize so many ifs and conjectures 
AA'ith regard to this theory of high temperature of 
.soil as a limiting factor in crop in-oduction, disjiosed 
to think the reports of actual experiment Avould be 
more to the purpo.se. The Avriter fully yields the 
point, but having busied himself in .standard lines of 
production and having little taste for the details of 
exacting experimentation methods, the theory and 
observation in .support of the same are here given 
for Avhat they are Avorth to thoughtful farmers and 
gardeners in general, and in the hope that the ex¬ 
periment station.s, especially the one located in Porto 
Rico, may become interested sufficiently, to inve.sti- 
gate it thoroughly by exact methods. 
Florida. n. l. haktman. 
Many farmers as far north as NeAvburgh, N, Y., will 
try late planted potatoes for seed. They keep potato 
seed in cold storage until about .Tuly 15 and then plant 
as usual. This crop groAvs until the vines are killed 
by frost. Then the tubers are dug and used for seed. 
tSuch seed gives great results. 
