Now this is interesting stuff this grafting larvae. During the second course I took, beekeeping level 2, we focused one day on queen grafting. What an ordeal.
We were given the grafting tool and told to get the larvae that were no older than 18 hours (to a maximum of 36 hours, no older). Right!!! So all the student gave their hand at it. We grafted 20 or so of these "invisible" larvae into queen cups and gave them to a cell building colony. Each student had their name put on their bar of cells to see how many cells were drawn out by the bees.
This was an excellent exercise. I only had 2 out of 20 that the bees worked on. Obviously when I attempted to graft this larvae that I could not even see, it did not come out with the royal jelly, or I squished it or something. It was a fun exercise, but very hard to do.
I think that if I were to ever try grafting again, I would use a headlight tool with magnifying glasses. I think that grafting goes on the assumption that if you see royal jelly, but cannnot see the larvae, that this is an egg that just hatched hours before, and that is what you want for the bees to raise to queen.
Before I do any queen raising, I would have to feel justified that I have enough colonies that I would feel that I would need to raise queens. Right now how I am feeling is that I am only a hobby beekeeper, and that perhaps buying good queens from a local reputable queen breeder would pay off in the end. I would be guaranteed of good laying characteristics, temperament, qualities that are important to make the apiary run quietly and be a nice place to go.
I had dealings with a hot colony last year. It was a swarm that I had caught the summer before. This colony was so protective, it gave me the willies to have to go and work with them. They were very cranky and protective. When I saw that swarm issue from them, I said good riddence to bad rubbish, and let them go. I gave them a new queen from one of the other colonies that I had raised some queen from and they were a little bit nicer, but still pretty cranky. Great day. Cindi