What are the opinions on the mixing of breeds within the same bee yard?
differemt :-D
i think this answer is the most common-let them bee, when they get bellow your quality treshold, requeen.
Cross breeding strains of bees can be both good and bad. There is a thing called cross-bred vigor that actually increases the performance/health of the resulting offspring. But you can also end up with bad traits from both sources being dominate. I have 4 hives and 3 different strains of bees in my apiary. 1 hive superceded the queen so her offspring will bea mixture or all 3 strains. I'm curious as to whether the outcome will be vigor or not.
I don't think it is really necessary to focus on pure-bred bees of a particular strain as that is not what is necessarily what is done in nature. What is necessary is selecting the most vigorous, most resistant results.