Young saplings in winter temperatures periodically

Question

I noticed a few days ago that the young saplings started unfolding their leaves already(except for the one in my pot outside, maybe frozen soil is preventing the growth of leaf buds for that sapling for now). Night temperatures have been below freezing while day temperatures have been above freezing. The trees are sugar maple, white oak(i think so at least), and elm(not sure at all what kind). I am in Columbus Ohio.

Is this normal for the leaves to start unfolding on saplings before the last frost? Is this freeze thaw cycle corresponding to day night cycle in March not a problem for saplings unfolding their leaves or is it a big problem with the potential of having the leaves frozen off? No new branch growth yet.

Answer 1

Yes, it's perfectly normal. Be aware that a frost is not the same as a freeze, so a drop in temperature overnight sufficient to produce a frost does not mean everything is frozen, it depends how low the temperature goes. If there is a genuine freeze, that is, temperatures drop below zero centigrade (32degF) and stay there day and night for a week (or more), then the leaves might shrivel and drop off - but the sapling will produce more when better conditions prevail. They may even shrivel and fall with a very hard frost, but again, will produce more later.

However, plants in pots are at more risk during an actual freeze, so if that happens for longer than a week, there's a risk the soil in the pot will freeze solid, and the roots of the plants within will be killed. Which means your sapling in the pot was at much more risk during winter than the ones you have in the ground - if the potted one does not produce leaves in the next month or two, you may have lost it.