QUERIES AND ANSWERS. 131 



in root, but it is not so stimulating to leaf production as guano or nitro- 

 genous manure. It is best applied in Winter, as in Summer it is very 

 likely to burn the leaves of the grass. Applied in "Winter, 1000 to 2000 

 pounds to the acre, the rains dissolve it and wash it into the soil, where it 

 gradually becomes assimilable as plant food to be drawn upon for use in 

 the Spring and Summer. It is quite continuous in effect. 



822. Q. Do local climatic conditions have much influence upon the Climatic 



., f. 1 . o Conditions 



growth of plants ? as Affecting 



A. It is both curious and very instructive to investigate the effects of ****n*'*' 

 climate upon garden vegetables grown from seed. lu fact a removal of 

 but a few miles from a locality is in some cases sufficient to produce 

 marked results, not because of a change of soil, for that can be mechani- 

 cally manipulated, at least on small patches for garden purposes, but 

 entirely because of change in atmospheric conditions. Thus, for instance. 

 Long Island fiirmers grow very profitable crops of cauliflower of most 

 inviting form, size and color, and with no more care than bestowed upon 

 a crop of cabbage, whilst no success whatever can be expected with a 

 field crop of cauliflower in the vicinity of Philadelphia, only one hundred 

 miles distant, even though the same seed be used — all attributable 

 entirely to a difference of climatic conditions of the two localities. The 

 influence of climate is also observed in the case of the onion, as in Con- 

 necticut there are grown, direct from the seed, thousands of acres of prof- 

 itable field crops of onions unrivaled in form, size and color, but the same 

 seed sown in Pennsylvania will only make sets, and poor ones at that, 

 often only stags. Again, Philadelphia-grown onion seed sown in the 

 vicinity of Philadelphia will always make sets, but it is never profitable 

 to make big bulbs, the climate is against it ; but in all other sections this 

 same Philadelphia seed will develop bulbs of full marketable size. 



823. Q. What is humus, and is it of much value? Humas. 

 A. It is a vegetable and sometimes partially animal mold, and is 



generally a black powdery substance in the last condition of decomposi- 

 tion. It may have been wood, straw, leaves, peat, or all of these and 

 more, exposed for a long time to moisture and the action of air. A good 

 example of vegetable mold turning to humus is that carpeting the ground 

 in old forests, a spongy covering obstructing evaporation and absorbing 

 rain and snow. Humus is dissipated by slow combustion in air, and in 

 decomposition forms nitric acid. Soils are fertile in proportion to the 

 humus they contain, and it preserves them in a loose state for air and 

 water to enter ; the loss of humus consequently results in a drying up and 

 hardening of the soil. It is valuable, as under the influence of microbes 

 and alkalines the humic matter is oxydized and a part transformed into 

 nitrates. Without humus in the soil no plants of the legume family, and 

 they comprise peas, beans and clover, can flourish. Possibly the reason 

 some soils fail to grow clover is because of the exhaustion of the humus 

 in them. 



824. Q. Why is it that a large quantity of onion seed of European imported 



Onion. 



