I would try to get a bigger sample size for spruce trees and see if the problem is continuing to happen. (Edit) I would also try to see if "Matchstick" and "Lollipop" trees can spawn with saplings in taigas as that is probably the problem.
Malockssomex Mastodon
I would try to get a bigger sample size for spruce trees and see if the problem is continuing to happen. (Edit) I would also try to see if "Matchstick" and "Lollipop" trees can spawn with saplings in taigas as that is probably the problem.