THE BREEDING OF COLD-RESISTANT FRUITS. 401 
THE BREEDING OF COLD-RESISTANT FRUITS. 
By Prof. N. E. Hansen (State Agricultural College and Experiment 
Station, Brookings, South Dakota, U.S.A.). 
In the great grain- and stock-growing region known as the prairie North- 
West, comprising the northern part of the Mississippi and Missouri 
river-valleys of the United States of America, considerable trouble has 
been experienced in the cultivation of the fruits brought originally from 
the milder and moister regions of Western Europe. The history of our 
western prairie horticulture records a multitude of failures from this 
cause. For example, it has cost, at a low estimate, over £20,000,000 to 
learn that the apples of Western Europe are not adapted to the climatic 
extremes of this vast continental region. The periodical crucial-test 
winters, such as 1855-6, 1872-3, 1884-5, 1898-9, show that they lack 
resistance against severe winter freezing. Many thousands of seedlings 
have been raised from this West European race in the endeavour to advance 
the limits of successful apple cultivation northwestward, but without 
permanent success, the test winters usually making an end to the experi- 
ment. The introduction of the Russian race of apples has advanced this 
limit far north and northwestward of the former limits, and rapid progress 
is now being made with their American seedlings and with crosses of 
the Russian with the West European type, the latter being usually known 
as the American apples. 
Plums from many countries have been tested upon this fertile inland 
plain, but after “‘ the smoke of battle” has cleared away, the native plums 
of the prairie North-West (Prunus americana) remain in undisputed 
possession of the field. Great advances have been made in breeding 
large plums of good table quality from this indigenous race; hybrids 
with plums from other parts of the world are also coming on. So rapid 
has been the progress with pure native seedlings that an ingenious 
western experimenter has ventured the opinion that our native western 
plums are really descendants from plums brought over in the Mongolian 
migration from Eastern Asia, especially Japan, by the prehistoric 
ancestors of the present North American Indians. 
The history of raspberry culture is in a measure a repetition of the 
failure of the apple—an utter lack of success with the West European 
raspberries. The native prairie race is now being ameliorated. 
While working in fruit-breeding since 1895 in South Dakota, and for 
some years previous to that time in Iowa, my endeavour has been to 
discover some underlying law in the ever-shifting panorama of phenomena. 
Two years ago the number of fruit seedlings was fully a quarter of a 
million; the number has since been augmented by the raising of many 
thousands of new seedlings, and decreased by the destruction of many 
thousands of inferior seedlings every year. 
The explanation that is to my mind the most satisfactory is the law 
of De Candolle, given in his “ History of Cultivated Plants.” De Candolle 
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