I know Resin, he isn't always correct of course but he does seem to know his conifers, I think he must have a good book on the subject as he has on birds. Books are not always correct, he got it wrong when I posted a photo of a bird on DG at a distance which I felt sure was a Green Woodpecker as I had seen it flying, however according to Resin they could not possibly be in my area because his book said so. They are here, with a colony not far away from me, I have even got photos of a young bird in my garden! The moral is, take information from anyone who thinks they know with caution, never take anyone's word for anything unless you are absolutely sure of it yourself.
My logical mind tells me it is very strange that there is a mutation with defective genes stuck amongst many of the same species which are perfectly normal, more so if you think these trees were affected by some sort of chemicals. There isn't enough of the yellow ones to think they could be older than the others, unless the land was mostly bare at the time. I wonder if there is any scientific evidence to prove Resin's claim? If there is it should be cited, otherwise be suspicious. Even if there are trees with defective genes producing this effect, that does not mean yours is one of them. It is often convenient for our minds to want to believe something which may fit a certain event, don't let your mind fool you.
Have you looked at the link I gave with Pinus strobus 'Aurea' ? If anything, it looks like that to me but there are many Pines and this one is not well represented on the internet. It is a beautiful tree, I would love to grow it but I'm afraid it would be too big for the space I have.
