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BROOKLYN BOTANIC GARDEN RECORD 
VOL. XXIII JULY, 1934 NO. 3 
REPORT ON WINTER INJURY TO THE 
\Wi@ ODN SwilANDTS «rN TEE BR@ OME AN 
BOTANIC GARDEN, 1933-1934 
Doubtless such extreme cold periods as we experienced during 
— 
the past winter have occurred intermittently since the beginnings 
of our present climate. It is obvious that they must be largely 
responsible for the northern limit of the range of our more tender 
native species. Not only this, but as the following report will 
show, extreme cold periods like that of the winter of 1933-34 
determine what kinds of exotics can be grown successfully in our 
region. During ordinary years, a given species may survive the 
winters and continue to flourish from year to year. But the de- 
cisive factor is the extreme low temperature periods that occur at 
rare intervals. Then the more tender species may be entirely 
killed. 
Extreme Weather Conditions in the Winter of 1933-34 
There were two periods of extreme cold in the winter of 1933- 
34. The temperatures and amount of snow on the ground from 
day to day are shown in the following tables kindly supplied by the 
New York City Station of the United States Weather Bureau. 
The first period (in December, 1933) was the less severe. 
Very probably if it had been the only one the plants would have 
suffered comparatively little. There are some features in it, how- 
ever, which are distinctly dangerous. First, the drop from a 
maximum of 54° on Christmas Day (which, by the way, was the 
highest temperature for the whole month) to a minimum of 12° 
above zero on December 27th is rather sudden. To be felt by the 
plant as little as possible, a change in temperature should be 
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