s is good. Vetches are good,
and soy beans are among the best for orchards. Clover, if you give it
time to make a good growth, is as good as anything.

The next question is--"Should apple raisers use commercial fertilizers?"
Now, the apple tree, when it is growing on good soil, makes such a
vigorous root development that it is hard to get any commercial
fertilizer to help it. On poor soils it, like any other kind of plant,
will respond to fertilizers. Some of the eastern experimental stations
have been carrying on investigations with commercial fertilizers for a
great many years to see whether in apple orchards these will cause an
increase in the yield or an improvement in the quality of the fruit. On
good soils, even after ten or twelve years' fertilization they have been
found to have no effect except in the case of nitrogen, and this can be
better supplied in the form of a green manure plowed under than in any
other way. That is to say, keep your orchard clean until the last of
July or first of August, sow your green manure crop, let it grow until
freeze-up and stay there during the winter time. It holds the snow and
so affords some winter protection. In the spring plow it under, and you
plow under all the nitrogen that the plants had collected the previous
year. Then keep your orchard clean during the summer time, until in July
or August you again sow the green manure crop.

[Illustration: Applying ground limestone to an acid soil to determine
whether liming will be profitable. Half of the field is left unlimed.]

The fertilizers that I get more inquiries about than any others are the
phosphates--bone meal, acid phosphate and rock phosphate.
Horticulturists have read that striking results are being obtained with
these on certain crops in the eastern and central states, and they want
to know whether the same fertilizers will pay here. Some inquire about
potash fertilizers. With the latter there is no doubt but that the
results we would obtain would, even under ordinary circumstances, not
pay. At the present time potash costs about ten times what it does in
times of peace. Sulphate of potash, which ordinarily brings $45.00 per
ton, is now quoted at $450. This puts its use out of the question.

The phosphoric acid fertilizers are no higher now than usual. They cost,
according to the kind, from $9.50 to $25.00 per ton. Some of them are
produced near here--in South St. Paul. With tree crops, apple, plum and
pear, we n