Professionals and people who rely on what pros say and do, take the temperature of the syrup as it boils. When it hits 219 F degrees, it is taken off the stove. I have tried using a candy thermometer, but find that it is hard for me to read. The steam gets on the glass and as soon as I take it out so that I can read it, the temp starts to drop so I don't get a true reading. Also, when there is only an inch of syrup in the bottom of the pan it's hard to keep the bottom of the thermometer off the metal. This is why I have been relying on the bubble method of telling when it is ready as well as relying on when looks like syrup, feels like syrup (on my tongue,) smells like syrup, and tastes likes syrup - then it is a duck! Just kidding. Therefore, it must be syrup.
I'll reconstitute the sugar this weekend. So far, the first quart looks fine. It's a nice amber color. Nice and clear. Minerals at the bottom of the jar.
We have a cold front coming in tonight. I'm curious to see how the trees will react to this. I really like my trees.