Commercial Fertilizers

Where manure is not available or where it

cannot be applied in sufficient amounts, commercial fertilizers may be

resorted to, after they have been experimentally tested out.

Leguminous cover crops are the best source of nitrogen, as has been

indicated, but where these do not grow well, or in seasons when they

have for some reason failed, nitrate of soda or dried blood are good

substitutes. From two hundred to three hundred pounds of one or the

other of these may be applied broadcast in the spring soon after

growth is well started and all danger of its being checked by frost or

cold weather is past. It is well to apply the nitrate of soda in two

applications a few weeks apart, especially on soils which are leachy

and in wet seasons, as part of the nitrogen may leach away if all is

applied at once. These should be thoroughly worked into the soil with

a spring-tooth harrow.



To supply the other two elements, from two hundred to four hundred

pounds of treated rock phosphate or basic slag for the phosphoric

acid, and the same amount of sulphate of potash for the potash, should

be applied at any time in the early part of the season, preferably

just before a light rain, and worked into the soil as before.

Home-made wood ashes are a good source of both these elements, and

especially of the potash. They cannot be purchased economically in any

quantity, but on the general farm there could be no better way to

utilize the wood ashes made around the place than by applying them two

or three bushels to a full grown tree every year or two. Wood ashes

are also a good source of lime, being about one-third calcium oxide.

Thus a large amount of available plant food will be supplied to the

tree, and where it is needed should result not only in better wood

growth but in the formation of vigorous leaf and fruit buds for the

following year.



Lime is not usually considered as a fertilizer except on soils

actually deficient in it. But it will usually be advisable to apply

from one thousand five hundred to two thousand pounds of fresh burned

lime or its equivalent, in order to correct any natural soil acidity,

to hasten the decay of organic material, to increase the activity of

the soil bacteria, and to improve the physical condition of the soil

by floculating the soil particles and helping to break up lumpy soils.

Lime also helps to liberate plant food by recombining it with certain

other elements in the soil. All these effects make a more congenial

medium for the leguminous crops to grow in, and it is frequently

advisable to use lime for this purpose alone. After this first heavy

application about 800 pounds of lime should be applied per acre every

four or five years.