Silver Birch trees

[markmack]

 I have 4 silver Birch trees along my back fence and I have noticed that the bees really seem attracted to new spring growth of leaves. Can anyone enlighten me about what it is that attracts the bees to this new growth?
     Cheers  :)

[jayj200]

most likely additives for propilius

[markmack]

Thanks JayJ   :)  Clever little girls aren't they!