I purchased 10 nucs of Russians in May. Brought them back to Texas and set them up in single deeps with feeders. I am located 35 miles NW of Lubbock(in the panhandle of TX). Had a late freeze which killed most of the wildflower bloom, so continued to feed them. They worked catclaw acacia and smartweed, then cotton started blooming. Hundreds of acres of cotton in every direction as well as corn(pollen cource). Pulled feeders off when cotton started blooming.
When first deep had 7-8 frames drawn(new pierco frames) I added second deep. Seems like it took forever for bees to start moving into second deep and drawing comb. Added supers to all hives when bees started drawing comb in second deep. Then I noticed two hives getting weak. I added a frame of brood from stronger hives to the weaker two. Didn't help much, one hive eventually was a dead out, other remained weak. No signs of disease or parasites.
First of October, moved the remaining hives to a field of late season sunflowers that were sprayed one time at the first of the bloom. Waited a week to move the bees on them as farmer said he wouldn't spray them again. Bees eagerly worked the sunflowers. I had pulled the single supers (which were empty anyway) from all but two hives(which were beginning to draw comb on a couple of frames). After three weeks on the sunflowers, the other weak hive was a dead out and another hive died out. There was no honey in the supers I had left on the two hives.
In the end, I lost three hives of Russians and got no honey from the others. This is my first year in beekeeping and I chose Russians. I'm trying to figure out what I did wrong. Any input about what I might have done wrong would be greatly appreciated as well as input on how to manage Russians. Thanks.