Thanks Ann & Mona.
I can't pack it in dry ice, but maybe an ice chest with regular ice. I'm not sure that I'll have room for an ice chest though. I'm sure it will thaw out though with regular ice.
Mona, I can't see how it would sweat. It was dry when I froze it, and whenever I've used it, it's never been wet, but maybe I'm wrong about that? I have thawed it out several times to use, and refroze it again, but it was always a very short time later. I've used the same pollen for two years, and got pods to set, so I know it's not going to be ruined just from thawing for a short time. I guess I'm just worried about it being okay if it's thawed out for a few days and then refrozen. We need to make sure that the freezer is totally thawed and drained, even though it's frost free before putting it in the moving truck. Otherwise I run the risk of it leaking water, and I don't want to take that chance.