378 BOTANICAL GAZETTE [JUNE 
Kuster’ found that during a specially mild winter the buds 
of maple did show a very slight growth both in the lateral organs 
and in the young axis. No new organs were started either in maple 
or other species examined, except rarely in Alnus cordijolia. 
ALBERT® found that practically all buds became dormant soon 
after leaf-fall until spring again. The first change in spring was 
a stretching of the tissues, further development of the parts taking 
place only later. 
It is a known fact in physics that the amount of heat absorption 
varies, among other factors, with the color of the body investigated. 
In other words, the same body if colored differently will absorb 
a varying amount of heat from a constant source, depending upon 
the color. Winter buds and branches are in many cases highly 
colored, and the question naturally arises as to how this affects 
the heat absorption of the bud during the winter and spring months. 
Regarding the extent to which color will affect heat absorp- 
tion, in addition to the records in works on physics, the experiments 
of WHITTEN’ are interesting. He found that thermometer bulbs 
wrapped in muslin of different colors, green, purple, black, and 
white, or with pieces of muslin of these various colors spread over 
them, or with the bulbs coated with a wash of similar colors, showed 
a marked difference in reading when exposed to bright sunlight. 
The average difference between the black- and white-washed bulbs 
was 16°, between the white and purple 15°, and between the white 
and green 13°. At one time a difference of as much as 21° between 
the white and purple bulbs was found. 
However, the actual experiments with buds have been rather 
few and the results are not so definite as one might wish. The 
most elaborate were those of WHITTEN described in the above-cited 
report. He selected a row of peach trees containing several vari- 
eties, and whitewashed them during the winter. During warm 
days of the unusually changeable winter the unwhitened buds 
swelled considerably, and during subsequent cold spells most of 
5 KisTEr, E., Ueber das Wachsthum der Knospen wihrend des Winters. Beitr. 
Wiss. Bot. (FUNFSTUCK) 2:401. 1898. 
6 ALBERT, P., Beitrage zur Entwickelungsgeschichte der Knospen einiger Laub- 
hdlzer. Forstl.-naturw. Zeitschr. 3: 345-376, 393-419. 1894. 
7 WHITTEN, J. C., Winter protection of the peach. Bull. 38. Missouri Agric. 
Exp. Station, April 1897. 
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