Your not supposed to burn pine I just use the fat end with an opposite skinny end, you stuff looks close to 16"? the shorter they are the harder it is to stack and keep stable. You could always buy a bigger stove and cut them longer
I had some other pine that wasn't near this bad. Yeah my stove takes 18" so I cut two 17" I will stack it up and jump up and down on it it will probably stay there Made some more progress, Hickory red and white oak put on the blanket and put it to bed for the night