VOL. LII. No. 2284. 
NEW YORK, NOVEMBER 4. 1893. 
PRICE, THREE CENT8 
$1.00 PER YEAR. 
BY THEIR ROOTS YE SHALL KNOW THEM ! 
MORE OF OUR UNDERGROUND FRIENDS 
What Grasses Do Beneath the Soil. 
Last week we grave some facts about the under¬ 
ground growth of corn, and explained how useful the 
roots are. This week we have a picture of the root 
growths of various grasses and grains, all taken from 
the report of Professor King’s interesting experiments. 
We compared the roots of corn to the drinking ap¬ 
paratus of a cow. That animal is called upon daily 
to do an immense work in digesting a 
great quantity of food and changing it 
into milk. The corn, too, does enormous 
work, and in its comparatively short life 
produces a heavier growth than any 
other farm product. It is somewhat 
different with the grains and grasses, 
and we might better, perhaps, compare 
their roots to the water power of a horse. 
The picture shown at Figure 238 (page 
731), shows simply the depths to which the 
roots of various plants descend into the 
soil. These do not attempt to show the 
total root growth, but simply their ca¬ 
pacity for digging into the ground. To 
obtain these specimens, cylinders were 
driven into the earth around the plants. 
Then the soil was washed out, leaving 
the roots. Of course this cut off many 
of the side roots, and gave the depth 
only. In the case of the wheat, roots 
from a Black oak tree, 34 feet away grew 
into the field, and were taken up with 
the wheat roots. They are shown in 
the coarse sticks that make the root- 
growth seem larger than it rea dy is. The 
Blue grass roots, you will notice, are 
comparatively short—26 inches only— 
yet they are thick and heavy at the top 
as we might expect from the tough sod 
given by this grass. Timothy, we notice, 
gives roots as long as clover, as do the 
grains. The oat roots are considerably 
heavier than barley, which at first 
thought is surprising. 
But we are not only concerned with 
the ability of these grasses to dig deep, 
but we also want to know what they 
can manufacture and store up for us 
underground. This is of great impor¬ 
tance to farmers who use a rotation, 
including grass, and especially so to 
those who use fertilizers in connection 
with a sod as a substitute for manure. 
What is the total root growth of these 
plants? To find this, Professor King 
grew plants of each in tight cylinders, 
so that the root growth was confined 
therein. The soil was washed away 
from these roots, and here is the result, 
at Fig. 234. The clover roots are shorter 
simply because the cylinder in which the 
clover was grown was not so long as the 
Dthers. The roots grew to the bottom of it. 
here. At the Storrs Experiment Station, in Connecti¬ 
cut, it was estimated that in the roots and stubble of 
an acre of clover—just as the mower left it there 
were 3,183 pounds of dry matter, which would give 60 
pounds of nitrogen, 15 of phosphoric acid and 45 of 
potash. Where the second growth was left on the 
ground, it was estimated that crop and roots contained 
76 pounds of nitrogen, 23 of phosphoric acid, and 90 
of potash. Thus we see that these roots are useful 
not only in life but in death as well, for after their 
work of feeding the plants is done, they provide an 
give that result. These figures may well astonish those 
who have not studied the matter • 
Bariev. 
Oats. 
Corn. 
Clover. 
Pounds of water per pound of dry 
matter. 
875 
525 
316 
564 
Yield, In pounds, per acre. 
14,196 
8,189 
19,184 
12,486 
Tons of water needed per acre... 
3,663 
2,152 
2,842 
8,367 
477 
8,1)17 
1,918 
You will notice that the corn gave a heavier yield 
per acre than any of the other plants, and yet required 
less water to produce a pound of dry matter. Pro¬ 
fessor King gives as a partial explanation the fact 
that much less water is lost from the soil by direct 
surface evaporation in the corn field 
because the surface cultivation arrests 
-- such evaporation, as we have often ex¬ 
plained. He also calls attention to the 
fact that the oats require more water 
per pound of dry matter than the bar¬ 
ley. That indicates that the oat crop 
is more exhaustive of moisture than 
barley, and explains somewhat why 
seeding to clover with barley is likely 
to be more successful than with oats. 
See, too, what an immense amount of 
water is demanded by the clover. This 
is very true of all the grasses. It shows 
how quickly the hay crop is injured by a 
drought, and how quickly it responds to 
a soaking either by rain or irrigation. 
This matter of artificial watering or 
irrigating was also investigated by Pro¬ 
fessor King. The following table tells 
its own story. In the field, the crops 
received simply the natural rainfall, 
while in the cylinders water was added 
as it seemed needed by the plants. The 
table, therefore, indicates what the 
crops yielded when supplied with the 
water they needed, and only what they 
could get. 
.—Natural Rainfall.—,,—Water added.—, 
Oats. Clover. Barley. 
The Total Root Growth of Different Plants. Fig. 
Dry matter, 
Ins. of 
Dry matter, 
Ins of 
OATS — 
per acre. 
water. 
per acre. 
water. 
1891. 
,.. 6,083 
13 91 
8,861 
19.6 
1891. 
8,189 
19. 
BARLEY— 
1891. 
... 4,157 
11.27 
7.441 
13.19 
Ib92.. 
14,196 
23.52 
Corn— 
1891. 
... 8,190 
12.26 
19,845 
26.39 
1892. 
... 7,045 
11.34 
19,184 
25.09 
234. 
After 
arefully estimating the total dry matter in an acre of 
uch plants, Professor King gives the following figures: 
TOTAL DRY MATTER, PER ACRE. 
Oats. Barley. Clover. 
In tops, pounds. 8,189 28 14,196 12,486 25 
In roots, pounds. 3,658.17 4,207.9 3,120.56 
There will be something of a surprise, we think, to 
earn that both oats and barley give a heavier root 
jrowth than clover, but there are the figures and 
.he picture. 
As to the fertilizing value of these roots, other ex¬ 
periments have been made to which we may refer 
abundance of plant food for other crops. It is evi¬ 
dent, too, that the heavier the growth above ground, 
the heavier the root growth will be. 
Other Views of the Water Question. 
Last week we spoke of the vast quantity of water 
needed to produce a crop of corn. Similar experi¬ 
ments were tried with barley, oats and peas. We give 
below the results of a single experiment in 1892. The 
table, omitting fractions, shows the amount of water 
required to produce one pound of actual dry matter 
in the various crops; also the yield per acre in 
pounds, and the tons of water needed on an acre to 
It is understood that an inch of water 
means the amount that would cover an 
acre to the depth of an inch. What 
could show better than that the advan¬ 
tage of having a perfect supply of water? 
Under natural conditions we seldom 
have water enough in our soils to get 
the best out of our crops. If we could 
irrigate and supply water at will, it is 
easily seen how our crops could be 
increased. You can see that the corn 
crop was doubled by the application of 
water just at the right time. Water not 
only makes up a great proportion of the 
bulk of all plants, but it gives the only 
medium in which plant food can be ab. 
sorbed. We see from these studies that roots and 
water are the two chief items in producing a crop. 
Plant food is of less importance than water, because 
it cannot be made useful until water is supplied. This 
subject is full of interest, and we shall have more'to 
say about it later. 
It is not strictly correct to say that the roots repre¬ 
sent the stomach in the plant’s system. As a matter 
of fact the leaves do the digesting and assimilating of 
the plant food. The roots are more the mouth and 
throat through which the food and water enter the 
body or stalk. The one great office of the roots i.s to 
enable the plants to drink their food. 
