What are you referring to? We don’t get much freezing temps here but we definitely have a dormant period. You’ll have to explain to me or point me to the literature where roots will continue growing year round. If the growth is so minimal as to have no real effect then why mention it? Not sure where this is from but all the studies I’ve read are in line with this graph.That's not true, roots will continue to grow in the winter as long as the soil isn't frozen.