EXPERIMENTS IN ORCHARD CULTURE.

SECOND REPORT.*

*

W. M. MUNSON.

It has been estimated that the average value of the fertilizing elements taken from an acre of soil by apple trees during the period of 20 years, counting in ten crops of fruit, is approximately $377. Of this amount $147, or a little less than 39 per cent, is in the fruit; $160, or about 42 per cent, in the leaves; and $70, or about 19 per cent, in wood for the growth of the tree. The total amount of nitrogen, exclusive of that used in the growth of the trees, is about 1,300 pounds, of phosphoric acid 310 pounds, of potash 1,900 pounds per acre.

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To restore the potash alone as above, and that used by the growth of the tree, it would require 21.7 tons of high grade ashes containing 5 per cent potash. To restore the nitrogen would require 16.2 tons of a commercial fertilizer containing 5 per cent nitrogen." In view of these facts, and also of the large amounts of fertilizing elements removed by crops of hay or grain, or by pasturing the orchard without giving extra feed to the animals, it is not strange that many of the orchards of Maine are deteriorating.

Of course, the fact should be taken into account that a portion of the material above referred to is returned to the soil in the way of fallen fruit and leaves and in the excrement of the animals, but with a liberal allowance for these returns the value of fertilizing elements actually removed from the soil during the period named will probably not fall short of $200, or $10 per acre per year.‡

As often urged in the publications of this Station, thorough tillage is one of the surest ways of rendering available the plant

*First Report see Bulletin 89, 1903.

† Roberts, Bul. 103, Cornell Exp. Sta.

A recent valuable contribution to the literature of th subject is Bul. 265, N. Y Agr. Exp. Sta. (Geneva).