BEES COLLECTING BOTH NECTAR AND POLLEN

I understand that bees tend to forage only one type of flower at a time. Is this tendency also true for nectar and pollen or will they collect both at once?

Bees will collect both nectar and pollen on one foraging trip but whether or not they do this depends upon the floral source being visited. If the flower which is being visited is secreting nectar as well as providing pollen, a considerable number of the foragers took both in studies conducted by R. L. White. He found that of more than 13,000 bees being observed, 25% were gathering pollen, 58% nectar only, while 17% were collecting both nectar and pollen on the same trip.