This topic just came up in another post, so thought I'd start a new thread to discuss directly. My opinion is they are not necessary (in most cases). We typically have abundant and diverse pollen here, and my colonies tend to get "pollen-bound" rather than the reverse.
With the SHB issues I've seen recently, I have basically stopped using them all together. I might use them to help a new split get started, new swarm I catch, or some special case like that, but if I do, those patties are cut into strips and the paper removed or really sliced up!
This time of the year, the patties are utilized by those wanting to produce NUCs or get strong build up for early splitting. In theory, the patties would be available to the colony on cold or raining days when they can't forage.
Pollen patties
Re: Pollen patties
What reedyfork says! I do use dry pollen substitute outside of my hives at the house starting shortly after December 21st, and add some pollen substitue to sugar bricks I use after the same date. I try and build up home hives to use as resources for other hives, but have to really fight swarming. Bees are more attracted to sugar bricks with pollen substitute in them than to plain sugar bricks. I am assuming, with out firm knowledge, that the substitute in the bricks does help feed brood, but if it only helps with getting nutrition to the house bees, I'm good with that.
As a bonus of open feeding dry pollen substitute, the change of bee behavior at the dry substitute also alerts me to when the red maple starts blooming, whether I can see blooms on nearby trees or not.
As a bonus of open feeding dry pollen substitute, the change of bee behavior at the dry substitute also alerts me to when the red maple starts blooming, whether I can see blooms on nearby trees or not.