Suggestions for Jarmers. 
Changes in Permanent Pasture or Meadow. 
Editors of the Cultivator —I am aware that the 
numerous correspondents of The Cultivator keep its 
pages so well stored with original communications, as 
quite generally to preclude the publishing of lengthy 
extracts from other sources. But the following re¬ 
marks of Prof. Johnston, upon u Permanent Pasture 
or Meadow,” evince so much accurate and extensive 
observation, and, withal, so entirely correspond with 
the experience of intelligent farmers, that they may 
well find a place, at some time, in your columns. With 
this view, I have transcribed the accompanying extract, 
and if you think as I do about it, just present it to your 
readers whenever you find room for it, and I doubt not, 
the perusal will interest them. F. Holbrook. 
When land is laid down to permanent grass, it under¬ 
goes a series of changes, which have frequently arrest¬ 
ed attention, and which, though not difficult to be un¬ 
derstood, have often appeared mysterious and perplex¬ 
ing to practical men. Let us consider these changes. 
a. When grass seeds are sown for the purpose of 
forming a permanent sward, a rich crop of grass is ob¬ 
tained during the first, and perhaps also, the second 
year, but the produce, after three or four years, lessens, 
and the value of the pasture diminishes. The plants 
gradually die and leave blank spaces, and these again 
are slowly filled up by the sprouting of seeds of other 
species, which have either lain long buried in the soil 
or have been brought thither by the winds. 
This first change, which is almost universally obser¬ 
ved in fields of artificial grass, arises in part from the 
change which the soil itself has undergone during the 
few years that have elapsed since the grass seeds were 
sown, and in part fropi the species of grass selected 
not being such as the soil, at any time, could perma¬ 
nently sustain. 
b. When this deterioration, arising from the dying 
out of the sown grasses, has reached its utmost point, 
the sward begins gradually to improve, natural grasses 
suited to the soil, spring up in the blank places, and 
from year to year, the produce becomes greater and 
greater, and the land yields a more valuable pasture. 
Practical men often say that to this improvement there 
are no bounds, and that the older the pasture, the more 
valuable it becomes. 
But this is true only within certain limits. It may 
prove true for the entire currency of a lease, or even 
for the life-time of a single observer, but it is not gene¬ 
rally true. Even if pastured by stock only, and never 
mown—the improvement will at length reach its limit 
or highest point, and from this time the value of the 
sward will begin to diminish. 
c. This, again, is owing to a new change which has 
come over the soil. It has become, in some degree, 
exhausted of those substances which are necessary to 
the growth of the more valuable grasses—less nutritive 
species, therefore, and such as are less willingly eaten 
by cattle, take their place. 
Such is the almost universal process of change which 
old grass fields undergo, whether they be regularly 
mowed, or constantly pastured only—provided they are 
left entirely to themselves. If mown, they begin to fail 
the sooner, but even when pastured they can be kept in 
a state of full productiveness only by repeated top-dres¬ 
sings, especially of saline manures—that is, by adding 
to the soil those substances which are necessary to the 
growth of the valuable grasses, and of which it suffers 
a yearly and unavoidable loss. Hence the rich grass 
lands of our fathers are found now, in too many cases, 
to yield herbage of little value. Hence, also, in near¬ 
ly all countries, one of the first steps of an improving 
agriculture, is to plow out the old and failing pastures, 
and either to convert them permanently into arable 
fields, or, after a few years’ cropping and manuring, 
again to lay them down to grass. 
But when thus plowed out, the surface soil upon old 
grass land is found to have undergone a remarkable al¬ 
teration. When sown with grass seeds, it may have 
been a stiff, more or less grey, blue, or yellow clay— 
when plowed out, it is a rich, brown, generally light 
and friable vegetable mould. Or when lpid down it 
may have been a pale-colored, red, or yellow sand or 
loam. In this case, the surface soil is still, when turn¬ 
ed up, of a rich brown color—it is lighter only, and 
more sandy than in the former case, and rests upon a 
subsoil of sand or loam, instead of one of clay. It is 
from the production of this change that the improve¬ 
ment caused by laying land down to grass principally 
results. In what does this change consist ? and how is 
it effected ? 
If the surface soil upon stiff clay lands, which have 
lain long in grass, be chemically examined, it will be 
found to be not only much richer in organic matter, but 
often also poorer in alumina than the soil which formed 
the surface when the grass seeds were first sown upon 
it. The brown mould which forms on lighter lands will 
exhibit similar differences when compared with the soil 
on which it rests; but the proportion of alumina in the 
latter being originally small, the difference in respect 
to this constituent, will not be so perceptible. 
The effect of this change on the surface soil is in all 
cases to make it more, rich in those substances which 
cultivated plants require, and therefore more fertile in 
corn. But strong clay lands derive the further import¬ 
ant benefit of being rendered more loose and friable, 
and thus more easily and more economically cultivated. 
The mode in which this change is brought about is 
as follows:— 
1. The roots, in penetrating, open and loosen the 
subjacent stiff clay. Diffusing themselves everywhere, 
they gradually raise, by increasing the bulk of the swr- 
face soil. The latter is thus converted into a mixture 
