Frost Damage

[Homestead Maple]

I heard last week that a sugar maker in NH wondered why his maple trees that were at a certain elevation seemed to have "fried" leaves. He went to the experts to find out what caused this and was told that the carbon emissions and other by-products from the Canadian wild fires this spring had affected a narrow band of trees south of these wild fires. That's a new one, considering trees from New York to Maine were affected, not just a narrow band.

[maplwrks]

I think it was caused by the late frost we had in the month of May. The leaves at a certain elevation were affected. Above this band, the leaves were not out enough to be affected, lower than this band the frost was not hard enough to freeze the leaves.

[Homestead Maple]

Most everyone that I had talked to about this agreed that it was a hard freeze that caused this and I agree. It's interesting what the experts had to say though.

[DrTimPerkins]

Most everyone that I had talked to about this agreed that it was a hard freeze that caused this and I agree. It's interesting what the experts had to say though.

I've only seen a short poster about this damage (at the NAMSC meeting in Ontario) which was putatively assigned to PAN pollution from the Canadian fires. Despite that conclusion, all the springtime damage that I've seen throughout areas of Vermont, NH, and upstate NY strongly appear to be freeze damage to me (and the first 10 yrs of my career were spent looking at freeze damage, although to red spruce instead of sugar maple). I've not been to the site these researchers looked at however, so will withhold judgement.

[Homestead Maple]

The damage at the site where the researchers visited was seen on sugar maple in other sites in Maine, Vermont, and New York and if I remember from those that reported, New Brunswick saw the same freeze. It also didn't seem to make sense that the damage to maple was at a certain elevation on the mountain sides and if it was due to the fires it would have affected maple at a wider elevation band, or would the toxic smoke layer only be so thick? The researchers said that only a narrow path of trees in NH were affected but maple tree leaf damage reports came in from a number of states.

[DrTimPerkins]

The damage at the site where the researchers visited was seen on sugar maple in other sites....

I can't comment on the specific site and damage they refer to, not having been there to see it myself. But I agree that it is unusual to think that with all the other damage around the northeast that occurred at the same time having been caused by freezing, that this one site would be due to something very different, yet all the other sites were also exposed to the same or similar levels of pollution.

[Homestead Maple]

I don't know how sensitive other tree leave types might be but it was interesting that only (from all reports that I heard) sugar maples were affected. Maybe it had to do with the growth stage at the time.

[DrTimPerkins]

I don't know how sensitive other tree leave types might be but it was interesting that only (from all reports that I heard) sugar maples were affected. Maybe it had to do with the growth stage at the time.

It has more to do with the phenological stage than anything else. When leaves first break out of their buds, they are quite sensitive to freezing temperatures. While still in the buds they are not....and once they are fully enlarged they are more hardy. That is why only certain elevational ranges got hit. It was the a combination of being in the right stage of leaf emergence and growth, as well as cold temperatures that did them in.

[RC Maple]

Assuming there are no other major stress factors this summer (drought, insect defoliation, etc.), then the trees should refoliate and be OK. Might be somewhat less sugar in the sap next season, and maybe somewhat reduced basal area (ring-width) growth, but you'll probably not even notice it.

Generally tree mortality only occurs when you have some combination of interacting stresses that occur repeatedly or over an extended time period.

We had substantial frost damage here in Underhill too. Trees have already mostly refoliated.

This is the only thread that came up when I searched for drought stress. Not only do we have very dry conditions, we had some 85 mph winds come through 2 weeks ago and cause a lot of damage - uprooted trees and limbs everywhere. I lost a couple of 24" trees that just blew over or broke off. Some of the sugar maples around have some leaves that are looking more brown than green. Our last drought here was 2002 and I wasn't paying as much attention to tree leaves as I was to corn and soybeans. Are these browning leaves a typical response and they're just suffering like the rest of us? Do they have a semi- dormant stage they go into like the lawn? I know some of these trees are older than I am and have seen it all before. Would anyone care to comment on what they've seen or know about trees handling these stresses?