ON THE MIXED HERBAGE OE PERMANENT MEADOW. 
1357 
amount of ammonia-salts, the herbage has become almost exclusively gramineous, 
Leguminosse are practically banished, and Miscellanese much reduced, both in number 
and in quantity. The grasses which have become the most prominent are of large 
habit and free growth, whilst those which are reduced are for the most part 
characteristically of an opposite description. 
For a number of years Dactylis was by far the most prominent, Agrostis, Alope- 
curus, and Poa pratensis, coming next; but, latterly, Dactylis has lost ground, both 
Poas have very much reduced, and Agrostis vulgaris , Holcus lanatus, and Arena elatior , 
seem to be coming much more to the fore in the struggle. 
The character of growth of the plot is essentially tufty and patchy; coarse strong 
seed-stems developing, with large, dark green, broad, “ flag ’’-like leaves, and the over¬ 
grown plants are often “laid,” and the crowns become more or less rotten before 
cutting, whilst the maturing is irregular and imperfect. 
It is not surprising that, with these conditions, there is not the same amount of 
growth, represented by carbon-assimilation, in proportion to the nitrogen and the 
mineral matter taken up, as where the smaller quantity of nitrogen is used. 
According to notes taken on the ground, the young plants, and perhaps those of 
Dactylis, Festuca ovina, and Holcus, more than others, are really injured by the direct 
action of the large application of the ammonia-salts. Indeed, it is probable that, whilst 
the deficient assimilation of carbon is partly due to deficient atmospheric conditions of 
light, heat, and moisture, and their favourable mutual adaptation to stage of growth, 
it is also, in part, attributable to some deficiency in the amount and capacity of the 
leaf surface over the total area of the plot, there being occasional blank, uncovered 
spaces, instead of a uniformly distributed close leafy “ bottom herbage,” and such plants 
as are prominent are forced to the extreme limit possible within the season-period of 
their growth, and do not attain maturity before the favourable climatic conditions for 
so doing have passed. 
A fact of interest which should not be overlooked is that, with a high percentage of 
nitrogen in the produce, and a high percentage of mineral matter also, there is, at the 
same time, a great depth of green colour, indicating, it may be presumed, an abundant 
formation of chlorophyll. We have, therefore, with abundance of nitrogen, of mineral 
matter, and of chlorophyll, what may be called conditions of fuller potential growth ; 
yet, in defect of the necessary climatal conditions, and, perhaps with a consequent 
limitation in the duration of the cycle of growth of the plants themselves, we have a 
deficient carbon-assimilation, in other words deficient growth over a given area. 
In the next Table (LXXIY., pp. 1358-9) are given the botanical results relating to 
plot 11-2, which was manured precisely as 11-1 with the exception that, in the seventh 
year, and subsequently, artificial silicates of lime and soda, or of soda alone, were also 
applied. In addition to the usual particulars, the increase or decrease in actual yield 
per acre of each species compared with the produce on 11-1 is given. 
MDCCCLXXXII. 8 L 
