1879.] 
AMERICAN AGRICULTURIST, 
91 
Science Applied to Farming.—XLIX. 
Field Experiments with Fertilizers.—What 
Farmers have been doing-. 
If I have ever cherished any skepticism as to the 
ability or earnestness of progressive farmers in 
studying and learning the ways to make their farm¬ 
ing better, it has been effectually removed by the 
reports I have received of held experiments with 
fertilizers last season. As will be remembered, the 
American Agriculturist proposed, last spring, some 
series of experiments, and arranged to provide the 
readers with samples of fertilizers for the purpose, 
of tested quality, and at prices just covering cost. 
Each article was put up in a small bag, containing 
euough for >/ 10 acre, and numbered I, II, III, etc. 
Every bag had a label giving amounts and propor¬ 
tions of its ingredients. The several small bags 
were packed in larger bags for shipment. Besides 
Nos. I to VII, which constituted “Set A,” there 
were a number of extras, so that the whole list in¬ 
cluded samples of all the more important fertilizers 
in the market. They averaged, on analysis, bet¬ 
ter than the guarantees. With each lot was sent 
a pamphlet, containing explanations and direc¬ 
tions for the experiments, and blanks on which 
any who might care to take the needed trouble, 
were requested to note the results and forward 
them to me. The Company by whom the fertil¬ 
izers were put up, supplied numerous sets to 
their customers; the Vermont Agricultural Col¬ 
lege distributed a number among the farmers of 
that State; the Maine Agricultural College made 
several series of experiments with them. Repre¬ 
sentatives of Agricultural Societies and prominent 
farmers in various parts of the country joined in 
the enterprise, so that the trials were made from 
Canada to Florida, and from Maine to Wisconsin. 
The Reports and their Value. 
The blanks for reporting experiments were sheets 
of paper, about 11 x 17 inches, with spaces for not¬ 
ing, on one side: (1) Description of soil; situa¬ 
tion, kind, texture, dry or wet, depth of surface 
soil, character of subsoil, etc., etc.—(2) Previous 
treatment, manuring, and yield.—(3) Weather dur¬ 
ing experiment.—(4) Fertilizers and how applied.— 
(5) Method of sowing, planting, tillage, etc.—(6) 
Other details and remarks. The other side was de¬ 
voted to details of size of plots, dates of planting 
and harvesting, amounts, quality, and value of 
produce in grain, roots, tubers, stalks, etc., by 
pounds and bushels ; calculated profit or loss, etc., 
Nearly sixty of these reports are before me. Some 
are brief, most are well filled and many entirely so, 
while several have additional interesting and sugges¬ 
tive statements covering a number of pages of fools¬ 
cap, for which there was not room on the blanks. 
In accuracy and fulness of detail, these reports 
far exceed my expectations. By uniting in experi¬ 
ments on a common plan, but with a great variety 
of places, soils, crops and other circumstances, the 
experimenters have, besides learning about the fer¬ 
tilizers, their soils and their crops, made an ex¬ 
tremely valuable contribution to our knowledge of 
the ways plants feed, and how fertilizers affect 
their growth. On the vexed problem of the capac¬ 
ity of corn to get its supplies of food from soil and 
air and the effects of fertilizers upon it, for instance, 
these reports throw more light than all the other 
experimental data I have ever been able to obtain. 
From a detailed account prepared for the forth¬ 
coming report of the Conn. Board of Agriculture, 
I condense a few statements of plans and results. 
Three kinds of experiments were suggested: (1) 
for testing soils; (2) for testing the action of fer¬ 
tilizers ; and (3) for obtaining more general infor¬ 
mation. It was recommended to have plans com¬ 
plete before starting, to select “ worn out ” soil for 
soil tests, and uniform soil for all, to lay out plots 
accurately, to diffuse the fertilizers well through 
the soil, to leave several unmanured plots for com¬ 
parison, to make accurate observations, to report 
them fully, and especially to arrange to carry the 
trials through a series of years. 
Experiments Especially for Testing- Soils. 
Suppose a farmer wishes to ask: “ What fer- 
UUzing materials doc* my soil most, need vs. order to 
Samples of Field Experiments with Fertilizers, 1878. 
Plot II. W. I. Bartholomew, Putnam, Conn.. .Hill land, dark loam, compact subsoil, worn out meadow. 
Plot 12. Halsey P. Clarke, Wyoming, R. I.......Loam, gravelly hard subsoil, worn out meadow. 
Plot 8. Nathan B. Lewis. Pine Hill, R. I.Upland, gravelly and light, gravelly subsoil, poor pasture. 
Plot HI. Chester Sage, Middletown, Conn.. ... .Heavy loam, hard-pan subsoil, worn out meadow. 
Plot 10. Ed. F. Smith, Tunbridge, Vt.Low land, heavy loum, compact subsoil, not adapted to corn. 
Plot 27. W. I. Bartholomew, Putnam, Conn.Plain land, gravelly loam, compact subsoil, in fair condition. 
Plot 29. S. W. Crocker, St. Albans, Me.Slatey and clayey loam, hard-pan subsoil, in poor condition. 
Plot 38. Prop. J. R. Farrington, Orono, Me.Moist heavy loam, underdrained, worn out meadow. 
Number of bag. 
Kinds and Amounts of Fer¬ 
tilizing Materials Applied 
pee Acre. 
No Manure. o 
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Die, Bone Black 
300 lbs. Muriate < 
of Potash 200 lbs. 
Nitrate of Soda 150 
lbs. Dis.BoneBlack << 
300 lbs. Muriate >-> 
of Potash 200 lbs. * 
VII 
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Farm Manure. 
No Manure. 8 
Valuable Ingredients Applied 
per Acre. 
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Cost per Acre... 
$7.50 
$5.35 
$4.50 
$10.88 
$10.13 
$9.75 
$15.38 
$0.80 
var’ble 
Yield pel Acre......__ 
bu. 
bu. 
bu. 
bu. 
bu. 
bu. 
bu 
bu. 
bu 
bu 
bu. 
II 
17.7 
18.7 
89.9 
19.1 
41 9 
21.1 
43.1 
51.7 
49.8 
13 
26.3 
85.1 
49.5 
35.1 
67.4 
67.4 
86.1 
55.6 
48.1 
26.3 
8 
7.5 
5.6 
20.7 
7.6 
28.8 
23.8 
27.5 
7 5 
32.5 
CORN. 
hi 
11.3 
21.5 
16.5 
62.3 
11.2 
68.9 
70.3 
84. 
43.3 
7. 
JO 
27.5 
35. 
85. 
32.5 
35. 
82.5 
85. 
32.5 
27.5 
40 
81.9 
[Average! 
24.6 
30.4 
33.5 
33.3 
39.1 
39.6 
42.9 
48.6 
28.9 
45.9 
24.4 
37 
130. 
162. 
200. 
125. 
310. 
220. 
250. 
150 
POTATOES. 
29 
60. 
76.6 
100. 
93.3 
106.6 
150. 
170. 
93.3 
146. 
60. 
Average* 
100. 
103. 
123.4 
129.6 
143.2 
153.4 
177.3 
106. 
132.9 
81.5 
TURNIPS. 
38 
225. 
285. 
815. 
240. 
428. 
203. 
413. 
518. 
263. 
300. 
* In Plots II and III, only 150 lbs. t Average of 27 experiments with corn. t Average of 9 experiments with potatoes. 
[Explanation of Table. —A little careful study of the above table will bring out its great value 
clearly. Thus, for example, in Plot II, the 150 lbs. per acre of Nitrate of Soda, costing $5,621, increased 
the yield of corn 1 bushel; 300 lbs. of dissolved bone-black (charred bones) added over 22 bushels at 
a cost of $5.25; while the two together (IV) added 24.2 bushels at a cost of $16.88, and 200 lbs. oi 
Muriate of Potash with these (VI) increased the yield by 34 bushels, at a cost of $15.38. In Plot III, 150 
lbs. of Muriate of Potash, costing $3.37i, increased the yield by 51 bushels. In the average of 27 different 
experiments on as many different farms, the greatest increase—a double crop—over no manure, is shown 
under No. VI, with the application of 150 lbs. Nitrate of Soda, 300 lbs. dissolved bone-black, and 200 lbs. 
of Muriate of Potash. But the greatest average profit was with No. V, where 200 lbs. each of Superphos¬ 
phate and Muriate of Potash increased the average yield of corn 185 bushels, at a cost of $9.75 Every 
figure in the table, compared with others, tells a story of its own, and the whole table may well be studied 
in detail, long and carefully, and in connection with the description of the soil given above.— Eds ] 
bring me crops?" Or to state it more fully: “Of 
the ingredients of plant-food which my crops must have , 
what ones can this soil furnish from its own stores, and 
what ones must I give it to make up the deficiencies in 
its supply ?—For this, an experiment was suggested 
in which the three ingredients of plant-food most 
important from the agricultural point of view, viz.: 
Phosphoric Acid, Nitrogen, and Potash, were to be 
used, each by itself; two by two, and all three to¬ 
gether. Results of some of these tests of the soil 
are given in the condensed table presented above. 
Soils in which Phosphoric Acid is Chiefly 
Heeded. 
In Mr. Bartholemew’s com experiment, Plot II, 
every portion which got phosphoric acid brought a 
good crop ; every one without it failed. The nitro¬ 
gen and potash both increased the yield, but 
reckoning a bushel of corn with its stalks at 80 cts. 
neither increased it enough to pay the cost. This 
experiment was made on the same field as the one 
reported for 1877, in which the crop rose and fell 
with the phosphoric acid, while it paid very little 
attention to the other ingredients. The experi¬ 
ment of 1877 was also repeated in 1878, with the 
same fertilizers on the same plots, and with al¬ 
most identical results. With 300 lbs. of super¬ 
phosphate per acre, the yield in the experiments 
of 1877, in the same repeated 1878, and in the new 
experiments of 1878, in every case came within 
about one bushel of 40 bushels per acre. With less 
superphosphate the yield fell off, while to get 
it much higher required other materials. Hog- 
manure, with superphosphate, gave a very large 
crop. Mr. Bartholemew’s experiment with pota¬ 
toes, No. 27, was made on another field, on low 
land, the corn being on the top of a hill. The 
potatoes were most helped by the phosphoric 
acid, but as seems to be oftener the case with them 
than with coca, responded profitably to the nitro¬ 
gen as well. In Plots 12, 8, and 29, likewise, the 
preponderating influence of phosphoric acid is 
clear, though the corn in 12 and the potatoes in 29 
are helped by the other materials also, as shown in 
several columns. There are, however, a good many 
Soils which respond well to Potash. 
In Mr. Sage’s experiment, Plot III, for instance, 
every crop with potash salts was large, every one 
without them a failure. The potash salts repaid 
their cost more than ten-fold. But while the pot¬ 
ash was most important, the other materials helped, 
and the combination of the three gave by far* the 
largest crop. This tallies well with Mr. Sage’s ex¬ 
periment on an adjoining field, described last year. 
Some of the reports give still more cogent illustra¬ 
tions of the great usefulness of the potash salts. 
Cases in which None of the Fertilizers were 
Particularly Useful 
are common; Plot 10 is 6uch a one ; Plot 8 gives 
very small crops also. Indeed, these experiments 
illustrate very forcibly a fact that few farmers ap¬ 
preciate, namely, that there are a great many soils 
which will not pay for the use of artificial fertil¬ 
izers, at least not until they are better tilled, irri¬ 
gated, drained, or otherwise improved. In short, 
the reports before me are full of illustrations of the 
important facts that: 
1. Soils vary widely in their capacities for supply¬ 
ing crops with food, and consequently in their de¬ 
mands for fertilizers. 
2. Some soils will give good returns for fertili¬ 
zers. Others, without previous amendment, will not 
3. The only way to find what a soil wants is to 
study it by careful observation and experiments. 
But these are only part and not the mos'tiimport- 
ant of the facts our experiments illustrate and 
prove. More another time. W. O. Atwater, 
Wesleyan University „ AliddirSamp Conn. 
