great extent of root system. Now see on the roots these white lumps, or
nodules as they are called. These contain nitrogen-gathering bacteria.
Some farmers in order to get more available nitrogen in the soil plant a
crop of some legume. Then these root masses with their treasures on them
are spaded into the soil.

"But most plants depend for nitrogen on manure. Whenever you see sickly
looking foliage know that nitrogen is lacking, and supply manure in
order to obtain it.

"The next element is potash. Its most common source of supply is wood
ashes, not coal ashes. One may buy potash in the form of the muriate or
sulphate. I told the boys before that potash was good for seed and
fruit. Pretty necessary to have in the soil, is it not? Stunted fruit
and poor seed mean lack of potash. Phosphorus helps in this work too,
and also assists in the forming of fine flowers. Bone ash and phosphates
are the sources of this food element.

"So if we just consider the classes of soils with which we have to deal,
remember the foods that must be had, and the effects on plants where one
(or all) of these is lacking, we have in our hands a help to soil
troubles.

"Take sandy soil--what is its greatest need? I should say humus. It
certainly should have more nitrogen. So add humus in the form of manure.
Spread it on your piece of garden plot anywhere from two to six inches
deep. This spaded in will, I think, do the work. You see sand allows
water to trickle away too fast. Water must be held properly in the soil.

"The clay soil really needs air. The good bacteria will not work without
this. So spade the soil up in the fall, and leave it weathering in huge
lumps. Sand or ashes added in the spring helps the air question too. A
sprinkling of lime over the surface tends to sweeten the entire soil;
for clay soil, so often too wet, is liable to get sour. Lime also adds
another plant food called calcium. It would not be bad to add some humus
in order to have an even greater supply of nitrogen.

"The lime soil, light and sweet, needs humus too. It should have this to
add body and ability to hold water.

"Sometimes it is well to add in the spring a sprinkling of phosphates;
that is a chemical fertilizer. Chemical fertilizers are like tonics to
the soil.

"All this very briefly puts us in touch with plant foods. I think you
all know from your school work that plants take their foods in liquid
form. These solutions of foods are very, very weak.