78 



FOURTEENTH ANNUAL REPORT OF THE 



is heavily charged with water vapor, 

 as is frequently the case, that within 

 the hive must be saturated. The ad- 

 ditional water produced by the bees 

 will therefore condense and run out 

 the entrance. It frequently happens 

 that the air inside is saturated while 

 that outside is capable of taking- up 

 this moisture again by evaporation, so 

 that there may be no w-ater visible 

 except within the hive, most often on 

 the cover, and possibly also on the 

 bottom board. 



If the wooden cover of the hive is 

 loose or if the hive is covered with 

 some absorbent or porous material, the 

 heat escaping from the cluster may 

 cause the formation of slight upward 

 ail' currents which w-ill carry the 

 moisture out the top in the form of 

 vapor. Out of doors there may be 

 condensation of moisture in the porous 

 packing more rapidly than it can be 

 carried off by evaporation, in which 

 case the packing becomes wet and 

 usually thereby less effective as a non- 

 conductor of heat. With sealed covers 

 the moisture must pass out the en- 

 trance and this may also occur in the 

 form of vapor if the outer air is of 

 sufficiently low relative humidity to 

 take up all the water as it comes out- 

 side. 



One of the much discussed questions 

 among bee-keepers is whether it is 

 better to have the wooden cover of 

 the hive sealed tightly by the bees w-ith 

 propolis or whether the replacing of 

 the cover with an absorbent cushion 

 to take up the moisture does not keep 

 the colony in better condition. The 

 usual method of providing upward 

 ventilation is to place several thick- 

 nesses of absorbent cloth or other 

 absorbent material over the frames, 

 over which is placed suitable packing 

 material. Out of doors care must be. 

 taken to have the cover waterproof so 

 that the packing and absorbent ma- 

 terial will not become w'et from rain 

 or snow. Another method used to a 

 considerable extent in New Tork state 

 is to have a small hole in the front 

 of the hive through which the moisture 

 laden air may escape. 



If the temperature of the inside of 

 the hive, not in the cluster, is low and 

 the humidity of the air which escapes 

 from the cluster is high, this moisture 

 will not escape from the entrance 

 without condensation. In such a com- 



bination of circumstances it is obvi- 

 ously advantageous to provide an 

 avenue of escape. This the upward 

 ventilation and absorbent cover does. 

 The late W. Z. Hutchinson who had 

 unexcelled opportunities for studying 

 bees in winter in North Michigan says 

 "Those bee-keepers who have been the 

 most successful in wintering their bees 

 . out of doors in the higher latitudes 

 have, so far as I know, given upward 

 ventilation through some kind of 

 packing material." Coggshall refers to 

 the severe winter of 1880 when in his 

 region (Groton, N. Y.) the temperature 

 remained below 0.0 °F. for three weeks 

 in January. Three-fourths of the bees 

 in New York died and he lost half of 

 his. Those saved had been packed 

 with burlap or carpet over the frames 

 over which was four to six inches of 

 dry sawdust. Bees in box hives died 

 unless the boxes had a hole for flight 

 half way up or were cracked so that 

 moisture could escape. 



On the other hand it is frequently 

 observed that colonies in box hives 

 sealed inside by the bees of^en winter 

 better than colonies in hives with 

 movable frames carefully packed. The 

 majority of box hives are much higher 

 than they are wide. This enables the 

 bees, by going toward the top, to keep 

 the temperature of the combs about 

 them high enough so that moisture 

 does not condense and furthermore • 

 there are frequently cracks to allow 

 the escape of moisture. 



In situations where the temperature 

 oi the combs and hive does not often 

 reach the point of condensation or if 

 a low temperature is prevented by 

 packing, a tightly sealed! cover can do 

 no harm and many bee-Keepers report 

 success in wintering bees in such con- 

 ditions. The attributing! of differences 

 in manipulation and methods to "lo- 

 cality" has been greatly overdone by 

 bee-keepers, particularly since they 

 usually do not describe the character- 

 istics of the locality or analyse their 

 conditions to determine why certain 

 things prove best. This peculiarity in 

 the bee-keeping literature is probably 

 largely to blame for the discussions on, 

 the virtues of upward ventilation. It 

 should be borne in mind, however, that, 

 while sealed covers may be harmful 

 in colder regions, upward ventilation 

 is not objectionable in warmer regions. 

 A careful study of the methods em- 



