1878.] 
AM E RIGAN AGKRICULTITRTST. 
55 
from the side of a mow, or stack, is so great that I 
wonder at myself that I have ever been contented 
to pitch off hay from the top of the mow, unless 
indeed I wanted to use some particular kind of 
hay, the location of which was accessible there. 
The obvious advantage of the use of the knife is 
that hay gotten in early, with the sweet fragrance 
of vernal grass, and clover, may thus be mingled 
with that of later growth, wiry, perhaps, and lack¬ 
ing in flavor, though not in nutrition, and some¬ 
times even in that, and this with the succulent 
aftermath perhaps, all together being highly relish- 
able. Its use admits of sorting horse from cow 
hay, or throwing out any that may have heated. 
Talks on Farm Crops—Mo. 12. 
By the Author of “ Walks and Talks on the Farm," 
“ Harris on the Pig," etc. 
“I have lately read several articles in the papers,” 
said Charley, “recommending rye as a green ma¬ 
nure for potatoes.” 
“This crop,” said I, “has certainly several 
things to recommend it for this purpose. It grows 
late in autumn, and early in spring, and thrives 
best on land most likely to be benefitted by plow¬ 
ing under a quantity of green vegetable matter.” 
“For our own use,” said the Deacon, “ we select 
potatoes grown on light, dry, sandy soil. They are 
cleaner and smoother than if grown on heavier 
soils, and are supposed to be of better quality 
than on low, rich, alluvial, or mucky land.” 
“On my farm,” said I, “the old men, who 
worked on it before it was underdrained, frequent¬ 
ly remarked : ‘ The east side of this field, or the 
north end of that one, or the west side of such a 
lot, is good for potatoes ’—and in every case they se¬ 
lect dry, sandy, rolling land. I have no doubt as 
to their general correctness. Still, since under¬ 
draining, we often get far larger crops on the rich, 
dark soil in the valleys. Last year we had a great 
crop of ‘Early Vermont’ potatoes on the lower 
portion of a field where, before draining, nothing 
would grow except coarse grass and rushes. The 
soil is a black, mucky sand. On this the crop was 
not only unusually luxuriant, and the yield large, 
but the potatoes were of remarkable excellence.” 
Facts of this kind lead us to suppose that pota¬ 
toes like a loose soil, rich in decomposed carbona¬ 
ceous matter. And, this being granted, it seems 
not unreasonable to conclude that it is a good thing 
to plow under some green crop, which will furnish 
a considerable quantity of carbonaceous matter. 
Eye is recommended for this purpose. 
“ And in addition to the carbonaceous matter,” 
said Charley, “ it is claimed that when we plow un¬ 
der a crop of rye in the spring, we turn under a 
large quantity of water which keeps the ground 
moist, and enables the crop to withstand drouth.” 
“These arguments,” said I, “are very plausible, 
but will scarcely bear a critical examination. In 
the first place, a crop of rye which, if cut and cured, 
would afford two tons of hay or straw, would not, 
in its greenest and most succulent condition, 
contain over 11 tons of water. The crop plowed 
under adds to the soil less than would be furnished 
by one-tenth of an inch of rain. Furthermore, the 
growing crop of rye would suck up out of the soil, 
and evaporate into the atmosphere, far more water, 
during a few days previous to its being plowed un¬ 
der, .than the crop contains. Lawes & Gilbert de¬ 
termined, by actual experiment, that on June 27th 
and 28th, 1870, an acre of fallow land, 41 ft. deep, 
contained 2,875 tons of water, while an acre adjoin¬ 
ing, in barley, contained, to the same depth, only 
1,951 tons of water. In other words, the roots of 
the barley had sucked up out of the soil, 924 gross 
tons of water per acre, equal to 1,034 of our tons. 
To grow a crop of rye, and turn it under for its 
water , is absurd. It would be much more reasona¬ 
ble to suppose that the good effect of the rye was 
due to its evaporating such a large quantity of wa¬ 
ter from the soil, and so making it drier.” 
“ There may be something in that,” said the Doc¬ 
tor. “ We are too much inclined to look on all our 
agricultural practices in reference to their action 
on the supply of plant-food. There are other 
things equally important, and draining is one of 
them. We drain to get rid of the water that the 
soil will not hold. If it holds 25 per cent of water, 
and it contains 30 percent, then wc drain to remove 
this 5 tons of water out of every 100 tons of soil. 
“Mr. Lawes found that the plot of land in his ex¬ 
perimental wheat field, which has received no ma¬ 
nure for many years, contained to the depth of 9 
inches less than 23i per cent of water, while the 
plot adjoining, which had received 14 tons of barn 
yard manure every year for 23 years, contained 
nearly 341 per cent of water. In other words, the 
9 inches of surface soil of the ‘no manure plot,’ 
contained 352 tons of water per acre, while the plot 
adjoining, only a few feet distant, which had been 
heavily manured for many years, contained 517 tons 
of water per acre. The land is thoroughly under¬ 
drained, and one plot, so far as surplus water is 
concerned, was probably just as wet and just as 
dry as the other. The examination was made in 
January, and we may presume that the no manure 
plot, at any rate, was saturated with water. It con¬ 
tained all the water it would hold.” 
“This is an interesting fact,” said the Deacon, 
“ and explains why our soils, when new and full of 
organic matter, did not need draining so much as 
they do after being cultivated and cropped for 30 
or 40 years without manure. It explains, also, why 
we suffer more from drouths than formerly. There 
is far less moisture in the soil than there was when 
the country was new r , and when the soil was full of 
what you call ‘natural manure.’ But I do not see 
what all this has to do with plowing under a crop 
of rye for potatoes.” 
“Simply this : ” said I, “ It is difficult to explain 
why the rye should do so much good as is claimed. 
It seems absurd to attribute this to the water in 
the rye. And it has not been proved that the car¬ 
bonaceous matter, which the rye gets from the at¬ 
mosphere, is specially needed by the potato crop.” 
Here is an experiment made in 1871, on a sharp, 
gravelly, overcropped soil, in poor condition : 
Plot 1—without manure, produced.70 bn. per acre. 
“ 2—with superphosphate and ammonia.186 “ “ 
“ 3— with superphosphate, ammonia, 
and potash.204 “ “ 
“ 4—with 20 tons farm yard manure.197 “ “ 
Plot 3—with ammonia, phosphates, and potash, 
and no carbonaceous matter, produced more potatoes 
than Plot 4, with farm yard manure, which, in ad¬ 
dition to the ammonia, phosphates, and potash, 
contained a large amount of carbonaceous matter. 
And we should expect a “sharp, gravelly soil,” to 
be unusually poor in carbonaceous matter. 
Now it may be taken for granted that the rye 
does not get anything from the atmosphere except 
carbonic acid. The nitrogen and mineral matter it 
gets from the soil. If you grow and plow under a 
crop of rye, you add nothing to the soil except car¬ 
bonaceous matter. And, so far as I can see, the 
good effect of the rye must be due to some of the 
following causes:—1. The roots of the rye find a 
quantity of soluble plant-food in the soil. They 
gather it up, and when the rye is plowed under, 
this plant-food is left in a more compact or concen¬ 
trated form. The roots of the potatoes can per¬ 
haps use it to better advantage than if it was dis¬ 
tributed through the 6oil.—2. The rve, by evapo¬ 
rating water, may make the subsoil drier during the 
winter and spring months, and to that extent have 
the same beneficial effect as underdraining.—3. 
The rye may get considerable carbonaceous mat¬ 
ter from the rain and atmosphere, and this, when 
the crop is plowed under, decomposes, and renders 
the soil more retentive of moisture.—4. The rye 
may keep the soil loose and render its mechanical 
condition more favorable for the potatoes. 
It cannot be doubted, from the facts which have 
been published, that plowing under a crop of rye 
sometimes proves of great benefit to the following 
crop of potatoes. But I have an idea that much will 
depend on the character of the soil and on the sea¬ 
son. The practice may in some seasons be a good 
one on some soils and not on others. If I had a 
crop of rye sown for plowing under as a green 
manure for potatoes, I would plow it under ; but if 
I had not, I should not despair of being able to 
raise just as good a crop by other means. 
If the growth of the rye makes the land drier, 
the same effect can be obtained by underdraining— 
or we can plant on land that does not need drain¬ 
ing. If the rye makes the land loose and mellow, 
good tillage will do the same thing. If the rye 
concentrates the nitrogenous and mineral plant- 
food, we can apply this same plant-food in artificial 
manures. If, in addition to this, it furnishes car¬ 
bonaceous matter, farm-yard manure will do the 
same thing. But after we have done all that we 
can do, we shall still be very much dependent on 
the season. And it will be a good plan to plant 
our potatoes at different times. 
Three years ago (1875) we had a remarkably fa¬ 
vorable season for potatoes. When the land was 
in fair condition, we had a good crop, whether 
we planted early or late, in hills or in drills. 
In 1876 we had a fair crop on very rich, well 
drained, warm, loose, sandy loam, when w r e plant¬ 
ed early varieties, early, kept the soil clean and 
fought the bugs. But late varieties, planted early 
or late, or early varieties planted late, were, on my 
farm at least, and also on the Deacon’s, a failure. 
Last year (1877) late planting of early or medium 
varieties gave fully as good a crop as early planting. 
In 1876 wc had a moist, growing spring, followed 
by a great drouth in July and August. And the 
drouth and the bugs left the late planted potatoes 
no chance to grow. The early varieties, when 
planted early, had got a good growth before the 
drouth seriously injured them. 
Last year we had a severe drouth early in the sea¬ 
son, and abundant rains in July, August, and Sep¬ 
tember. Hence the late planted potatoes, where 
the soil was favorable, grew rapidly, and produced 
a fair crop. I had several acres of “Late Rose” 
potatoes, planted on June 16th and 17th, that made 
a vigorous growth, and gave a good crop. The 
land was a clover sod in fair condition, turned over 
immediately before planting, and no manure used. 
If the season is favorable, and the land is clean 
and mellow, a late planted crop of potatoes will 
have a ranker and more luxuriant growth, than a 
crop planted earlier in the season. My early plant¬ 
ed potatoes, last year, were liberally manured, but 
the vines were never as dark colored and vigorous 
as those planted late without manure. 
Where “ Early Rose ” or “ Early Vermont ” pota¬ 
toes are grown for an early crop, it is necessary to 
plant early and manure liberally. We have to 
“ force ” them—not by artificial heat, but by extra 
manuring. An unnaturally early crop is a costly 
crop, and is only profitable where we can get an 
extra price. Where “ Early Rose ” potatoes are 
raised, as they are to a considerable extent in this 
section, for sale as a common farm crop in the fall, 
it is very doubtful whether we can afford to plant 
them very early. They require much richer land, 
or more manure, than they do when planted later. 
“ That is all true, theroretically,” said the Doc¬ 
tor, “ but as a matter of actual practice, I suppose 
our friend, the Deacon, will tell us that it depends 
a good deal on the season; your suggestion to 
plant part of the crop early, with liberal manuring, 
and part late, with less manure, is safe and sound.” 
“Well,” said the Deacon, “I had about con¬ 
cluded that we should have to plant early kinds of 
potatoes, and plant them early, so that they would 
get out of harm’s way, or the bug’s way, before har¬ 
vest, but I am not sure that late planting of early 
potatoes will not sometimes give better results. It 
will depend on the season. The main crop of po¬ 
tatoes will be raised, not from an early variety, nor 
yet from a late variety, but from a half early or 
medium variety like the ‘Late Rose,’and it will 
be planted just before or just after corn planting.” 
I presume the Deacon is right. But if I had 
very rich land in prime condition, and wanted a big 
crop of autumn or winter potatoes, I would plant 
the “Late Rose” as early as the condition of the 
land and other spring work would admit—say as 
soon as we had sown our barley and oats. 
“ But suppose,” said the Deacon, “you had poor 
laud ? ”—“ Even in that case,” said I, “ early plant¬ 
ing gives us the best chance. I would plant early, 
in hills 3 feet apart, and use large sets with only a 
few eyes in a set, and only one set in a hill.” 
“I have known just as good crops,” said the 
Doctor, “raised from small seed as from large.” 
