288 MINNESOTA STATE HORTICULTURAL SOCIETY 
Mr. Wright: I leave room enough in the center to run the 
cultivator through, but I mulch inside of the row thoroughly, leay- 
ing about three feet in the middle. 
Mr. Yahnke: Which do you prefer, wire or mulch? 
Mr. Wright: Mulching has paid me a little better. Where I 
used wire I did not mulch the last two years I cultivated, and the 
berries dried up on that patch this year. 
ROOT-KILLING OF APPLE TREES. 
PROF. N. BE. HANSEN, BROOKINGS, S. D. 
Prof. Hansen, (S. D.): This morning, at the meeting in the city, 1 
spoke something on the subject of root-killing. The substance of a bulletin 
on root-killing American trees was published last month in the Minnesota 
Horticulturist, so I need not go into that matter here. 
If any of you desire to see specimens of the true Siberian crab you can 
do so after the close of the meeting. Some of them will be new to all of 
you. These came from Prof. Sargent, and he obtained them from Dr. 
Riegel, the director of the Botanical Gardens at St. Petersburg. The true 
Siberian crab will not root-kill at Lake Baikal, in Manitoba or Assiniboia, 
where the temperature goes down to sixty below, with very little snow in that 
country, and apples that will stand that should be considered hardy. This is 
a pure pyrus baccata; you see a pure specimen of the pyrus baccata. The 
way you can always tell the true Siberian crab is that the calyx, or blossom 
end, is perfectly smooth, whereas the other crab is the same as an ordinary 
apple, and the calyx or blossom end does not fall off at the time of ripen- 
ing. This is the hardiest little specimen of the apple. This (indicating) is 
a specimen that stood a temperature of forty below with no snow. After I 
had been to Russia I solved the problem of root-killing. The point I want 
to make is this, there is no standard apple that is hardy, that will stand our 
Dakota conditions; the Anisim and Antinovka, seedlings of the Hibernal 
type, and a standard apple, were black as a hat last spring—so we have cut 
it out. I have-here an apple, a wild apple from the Province of Koursk in 
southern Russia, and apples that were perfectly hardy there have gone out at 
Brookings. You talk about a long scion with a short root—they all went 
out last winter. 
Mr. Burnap, (lowa): Did you not report that the roots of the scion 
would make the tree hardy? 
Prof. Hansen: That was the first winter, and I had only a single tree 
that stood; all the others in that same lot were killed. The point then is 
that the Russsians find they must go outside their own apples for a hardy 
root. There is no form of standard apple that will stand severe freezing 
without any snow on the ground, so they have come to the Siberian for 
stock. In a general way, it makes the tree two or three years earlier and 
a slightly dwarfish tree. Since the publication of the bulletin I have received 
some more evidence. Dr. Luger, of the Swabian government, is a fore- 
most authority on pomology, and he has published a great many books. 
Here is what he says of the use of the pyrus baccata as a stock: “Pyrus 
baccata and pyrus prunifolia is recommended as half standard for the culti- 
vated apple in dry, shallow soils.” You see he recommends it for dry, 
