1 879.] Seed-Breeding. 559 
sixteen hills under like treatment has been as 1 to 3J by 
weight of corn on ear, and as ij to 6f lbs. of stover per hill. 
Under ordinary manuring the difference has been nearly or 
quite as great. Under insufficient manuring the variations 
appear even greater. We desire to lay stress upon this faCl, 
that manuring does not produce crop by itself, and that 
increase of manure is not necessarily followed by increase 
of crop. We know of a field which received thirty-five 
cords of manure per acre, and yet another field fertilised 
with six or seven bags of Stockbridge corn manure to the 
acre gave a larger and fairer yield of corn. On Waushakum 
farm, one rather poor (as we have considered it) piece of 
land, which has been heavily cropped by the aid of Stock- 
bridge manures in past years, yielded 66 bushels of corn 
this year when manured with seven bags of Stockbridge 
fertiliser ; while another field, considered our best land, 
manured with about 5J cords of clear cow-dung and six 
bags of Stockbridge fertiliser, yielded 66 bushels (or exactly 
131J, and 132 baskets of 41 lbs., respectively, per acre). 
Hence manure is but an element, an important one, but not 
sufficient in itself to furnish us large increase of crop. 
Will cultivation do it ? We can say also the like for our 
culture, that it is an important faCtor in the improvement 
of corn, and yet is not all-sufficient, being but a faCtor. In 
an experiment to determine this we took a suitable plot of 
ground, and manured it most excessively, so as to eliminate 
by the abundance of fertility the specific effeCt of the ma- 
nure in producing differences between the yields (some 
forty-two cords of cow-dung per acre, besides abundant 
chemical fertilisation), and planting in hills 4x4 feet apart, 
three kernels to each hill, using selected corn and equiva- # 
lent conditions of planting : we had three plots, each con- 
taining sixteen hills. Plot I. received no culture whatsoever, 
the weeds being pulled by hand. Plot II. was hoed tho- 
roughly and frequently during the season. Plot III. was 
weeded by hand, as Plot I., but a knife was run vertically 
around each hill to the depth of 6 or 7 inches, at various 
times during growth. The following are the results of 
harvest; — 
Table I. 
No. 
Weight 
Weight 
Proportion of 
No. 
Length 
of 
of corn 
of 
ear-corn 
of 
of 
hills. 
in ear. 
fodder. 
to fodder. 
ears. 
ears. 
Plot I. 
16 
29J 
72 
i ; 2*46 lbs. 
86 
64 3f ins. 
„ II. 
16 
37 t 
8l 
i : 2-1 7 „ 
92 
752 „ 
„ III. 
16 
33f 
48* 
1 : 1*44 „ 
104 
774 » 
