52 SOURCES OF NECTAR 



other insects, including bees and wasps, are attracted to the feast 

 when the product is abundant. 



At times the plant lice become so abundant on the leaves 

 of the various trees on which they feed as to prove disastrous to 

 the tree. Plum trees are especially liable to injury from these 

 insects. When the leaves begin to curl in early spring, it is 

 usually a sign that plant lice of some kind are present. Hundreds 

 of them will be found under one leaf. 



It is usually from such forest trees as elm, hickory, and oak 

 that honey-dew comes in sufficient quantities to be apparent 

 in the hive. It is only in an occasional season that the bees 

 gather honey-dew in noticeable quantities. At times it will fairly 

 drip from the trees, and on such occasions, if no honey is coming 

 in, the bees will work with tremendous energy in storing the 

 substitute. 



There seems to be considerable variation in the quality of 

 the honey-dew honey, but as a rule it is not of good quality, and 

 a bee-keeper should be very careful that it does not spoil his 

 market for good honey. It is especially disastrous to the bees 

 as winter food, and should never be left in the hive for winter 

 stores, in the northern States, where the bees are confined for long 

 periods without a flight. Where the bees are free to fly every few 

 days during winter, the bad effect is not so apparent. (See 

 Chapter XIII on Wintering.) 



Sources of Early Pollen. — While some pollen is gathered 

 from the early spring flowers, the most important sources are 

 the forest trees. The elm is especially valuable, as it yields pollen 

 in enormous quantities. When the elm trees bloom, the 

 bees fairly cover them until the humming reminds one of 

 the swarming season. At about this same season the maples 

 (Acer) bloom (Figs. 25 and 27). These trees furnish not only 

 pollen, but nectar also, and are a valuable source of supply at this 

 season. The willows (Salix) likewise furnish pollen in abund- 

 ance and nectar beside (Figs. 25 and 26). At times the bees 

 are able to store some honey from the two last named sources. 



