SCIENCE AND INDUSTRY. 
The best possible crops to. grow for green-manuring purposes are 
the legumes, such as cowpea, Mauritius bean, velvet and soya beans, 
lupins, vetches, &e. Among the advantages’ of a green crop are the 
following -— ‘ 
(1) During growth the ground is shaded and moisture is con- 
served. (2) Erosion of fine earth is prevented during heavy rains. 
(3) Weed-killing is promoted. (4) The deep tap-roots of legn- 
minous plants bring available plant-food from the subsoil to the: 
surface soils. (5) The interposition of a crop, other than cane, 
that will act in minimizing fungoid diseases and insect attacks. 
_ If the habitat of parasites attacking the cane is removed for a time, 
it must result in their dying out or disappearance. (6) Crop 
rotation. - 
Nitrogen is the soil element that becomes the most quickly exhausted, 
as it is also the element that is the most expensive to purchase. ‘The 
best time to plough-in green crops is at the time the seed in the pods 
is in a milky condition. 
Se 
SEeLecrion oF PLAnts. 
1 
This is a highly important matter to which too much attention 
cannot be paid. i 
Generally speaking, plant cane from ten to twelve months old, or 
first ratoon of the same age, should be taken. If the time of planting 
corresponds to that of harvesting, it is a good plan to cut as many top 
plants as possible from the best of the cane going to the mill.: These 
are undoubtedly superior to the parts of the cane situate lower in the 
stick, although it is claimed that butts also make very good plants. © 
The top plant, however, has the minimum of sugar, and contains 
nitrogenous bodies and salts which form food material for the plant 
during its early stages of growth. Top plants cannot always be 
procured, and it is then usual to cut up the whole stick for plants. 
Cane plants should be brought from colder to warmer climates, and from 
hillsides to lower levels, where it is invariably found to do well. 
The best width of row has been found, from numerous experiments 
in Louisiana, Hawaii, and Queensland, to be 5 feet; though, in the case 
of a straight-growing cane, such as “ D.1135,” this could be reduced to 
4 ft. 6 in. The drilling is best accomplished by means of a double 
mouldboard or drill plough. The plough should make a good wide 
drill about 9 to 10 inches deep in the loose soil. Where the cultivation 
has been deep and good, this will leave a few inches of soil for the 
plant to lie on. Ina dry time, when planting by hand, there is usually 
a certain amount of moisture in this loose soil into which the plants 
can be pushed down, and so give them a much better opportunity to 
strike more rapidly. _Three-eye plants are almost universally favoured, 
but the distance at which the plants are to be spaced apart in the row 
varies greatly in the different districts. At Bundaberg, the plants are 
often placed 12 to 18 inches apart, while on the Herbert River the 
planting is almost continuous. A good average distance for the spacing, 
and one found to give good results, is 6 inches. The plants are usually 
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