1 Ocr., 1897.] QUEENSLAND AGRICULTURAL JOURNAL. | 325 
II. Tux Yirtp witn Comprere Manovre. 
Bushels per Acre. 
1884, to 1891 inclusive, 8 years, average per year oa w. 1642 
TY 5 EEE} gy, IK, - * fh on PEERS 
1887 ,, 1891 7 (5 crop years) Ay fr ... 262°8 
1887 ,, 1893 7 (ies ees a) 5 are ... 262°0 
III. Tor Yrenp wire Barnyard Manvre. 
Bushels per Acre. 
1884 to 1891 inclusive, 8 years, average per year xr ... 169°3 
1884 ,, 1893 7 5) as or vee L94°7 
1887 ” 1891 ” (5 year crop) ” oo ee 271°3 
1887 ” 1893 ” (7 29 ” ) ” La eee 2768 
IV. Tue Recative YIELD IN AN UNFAVOURABLE SEAsoNn. 
Bushels per Acre. 
1889—Unmanured ... ie Aes ox) oon on Pe 10:9, 
1889—Fertilised ... ori on nee ms eee ... 152°5 
1889—Manured ... rey nn 
on on vee ... 1625 
The first point of importance and value observed is in reference to the number of 
crops that were secured. On the unmanured land the crops secured after eight years 
were so small as to materially reduce the average for the whole period; while for the 
_manured land the average for the whole period was not only not reduced but. very 
materially increased—that is, the crops secured on these, after the trees on the 
unmanured land had practically ceased to bear, were greater proportionally than 
those secured previous to that time. This was true both for the fertilised and 
manured land. 
In the next place it shows that the yicld was very materially increased by the 
use of manures, either in the form of artificial or natural supplies; and the differences 
in yield derived from these two forms are very slight, indicating that very much 
smaller amounts of actual plant food in quick acting forms were quite as useful as 
pares amounts of the less available forms in which the food exists in natural manure 
roducts. 
u For the ten years the fertilised plot received 240 Ib. of nitrogen, 560 lb. of phos- 
phorie acid, and 740 Ib. of potash, while the yard manure plot received—assuming the 
average composition of yard manure—2,000 lb. of nitrogen, 2,000 lb. of phosphorie 
acid, and 1,000 lb. of potash; yet with eight times as much nitrogen, nearly four 
times as much phosphoric acid, and more than twice as much potash, the yield was 
but 113 baskets greater or 11 baskets per year. There was no actual difference 
in the size of the trees on the two plots; in both cases they were larger and for the 
most part healthy, and when the experiment was concluded it was not caused by the 
normal dying of the trees, but by the fact that the larger number of them were 
partially or wholly destroyed by a severe windstorm. 
In the third place it is interesting to observe—and it is a point of great 
importance—the effect of an abundance of food in overcoming unfavourable weather _ 
or seasonable conditions. The year 1889 was extremely unfavourable, and the crop 
throughout the State was small. In this experiment the unmanured plot vielded at 
the rate of 10°9 baskets per acre, while the manured and fertilised plots both showed 
a yield exceeding 150 baskets per acre. The manure strengthened and stimulated 
the trees, and enabled them successfully to resist such conditions as were fatal to the 
crop on the unmanured land. 
This point is one that is seldom considered in caleulating the advantages to be 
derived from proper manuring, though it is of extreme value, since the expenses of 
cultivation, trimming, and interest on investment are quite as great in the one 
case as in the other. 
Another experiment bearing on. this point, recently reported by the Cornell 
Experiment Station, is also very instructive, as indicating the need of manures for 
fruit trees, not only in reference to the amount removed, but also in reference to the 
proportions of the essential constituents required. 
This study shows that the plant food contained in twenty crops of apples of 
15 bushels per tree and thirty-five trees per acre, and in the leaves for the same 
period, amounts in round numbers to 1,337 lb. of nitrogen, 310 lb. of phosphoric acid, 
and 1,895 lb. of potash. These amounts of plant food are compared with the amounts 
that would be removed by twenty years’ continuous cropping with wheat, assuming 
an average yield of 15 bushels of wheat per acre, and 7 lb. of straw to 3 bushels of 
grain—viz., 66 lb. of nitrogen, 211 1b. of phosphoric acid, and 324 1b. of potash. By this 
