What happens to broadleaf deciduous trees during winter in warm climates like Southern California or Florida? Do the leaves turn color? Fall off?
I live in SC, about 120 miles north of Fla. Will that do? What happens to the deciduous trees here? The same things that happen to them everywhere else. By definition, a deciduous tree is one which loses its leaves. Many of them (oaks, maples, sumacs, etc.) turn into beautiful colors before they fall.
Some broad-leafed trees do not change color and fall off all at the same time in the autumn, such as the live oak. (Hence, the name.) However, it, too, loses its leaves, but in the spring and they do not change color.
My understanding that it is lengthening/shortening daylight hours that cause plants to know the change of seasons, not heat/cold as such.
We do have four seasons in SC. Winter is just not so severe. The leaves here change color later. You can check the weather bureau’s foliage color maps in the autumn and note that the further south you go the later the leaves reach their height in color. Yet, the daylight hours are the same at the same time in SC as they are in NY, so I don’t think that’s the reason.
We need a tree expert. I’ve always understood that deciduous trees lose their leaves and go nearly dormant to preserve water during dry times and short days which provide less sun for photosynthesis.
But, on our golf course the trees are irrigated winter and summer so there is no dry season but the trees still lose their leaves.
The daylight hours can’t be the same in North Carolina and New York — they are at different latitudes. The farther north you go, the longer the summer days and the longer the winter nights. The tropics, on the other hand, have a fairly consistent amount of daylight all year round.
July 27
Albany, New York:
Sunrise:
5:43 AM
Sunset:
8:20 PM
Total daylight time: 14:37
Charleston, South Carolina
Sunrise:
6:21 AM
Sunset:
8:34 PM
Total daylight time: 14:13
December 22
Albany, NY
Sunrise: 7:23 a.m.
Sunset: 4:25 p.m.
Total daylight time: 9:02
Charleston, SC
Sunrise: 7:19 a.m.
Sunset: 5:18 p.m.
Total daylight time: 9:59
Close, but not quite. Days in fall and winter are going to be longer the farther south you go. The limiting cases are the North Pole, where the length of daylight is 0 hours (the sun doesn’t rise after the autumnal equinox), and the equator, where the length of daylight is 12 hours on any day of the year.
I looked up Charleston and New York on sunrisesunset.com , and the difference in day length is about 45 minutes on December 21. It would be less at any other time of year. I’m an ex-astronomer, not a botanist (ex- or otherwise), so I don’t know if this is enough to make the difference in leaves changing color or not.
In Houston and Austin the leaves do for the most part turn brown and fall off. I should know, I had to rake them all the time. It sure beats raking dead pine needles though. Its not as drastic as I think it is further north though. I think they fall later in the year around November and December here, and they don’t seem as bare as I always imagined how trees look in the North. I’ve never been up north in the fall so I can’t really say.
Seems to me that the leaves change color, they just do it at different times. In New England it seems that all of the trees pick the same two or three weeks for their leaves to change colors and fall, and the pictures I’ve seen are spectacular. In Texas, you can look out over a green hillside and pick out two or three patches of spectacular orange where a tree is losing its leaves, and this pattern is constant for three or four months. And then there are certain oak trees that slowly lose their leaves as said leaves are replaced, so it’s not really obvious. Not nearly as impressive, but still, it makes for nice splashes of color.
Deciduous trees shed their leaves because the leaves lose their chlorophyll, which, incidentally, is the main reason for the fall colors. (The disappearance of the chlorophyll discloses underlying colors hidden by the green; however, the vivid reds and purples are created anew - this was discussed in a prior thread several years ago.) Trees lose their chlorophyll to save energy, but the evergreens don’t. I don’t think it’s a water issue, as the summer is likely to be more arid than the winter. Shorter days? Perhaps, but why do deciduous need to do this but not evergreens?
I live in Los Angeles, and yes, the leaves turn colors and fall off. New growth in spring does come much earlier here, depending on our weather in February and March.
Maybe so. Just the same the air in winter is exceedingly dry, the moisure having been frozen out. Deciduous trees lose lots of water through their broad leaves. In winter they would lose even more than in summer because of the dryness of the winter air. The loss of leaves in winter cuts down this loss. Conifers and native desert vegetation have needles with a hard and waxy surface which loses water much more slowly. I don’t know whether the loss of leaves is a water preserving mechanism or whether the water-loss reduction just a finge benefit. However, I live on the desert where the air is dry most of the time, winter and summer. Deciduous trees lose their leaves just like in Iowa and at about the same time of year.
What a coincidence! I just watched an old (vintage 1980) NatureScene program on ETV, with Rudy Mancke, titled “Autumn Colors.” Discussing the autumn foliage and the fall of the leaves, Rudy said that cold has something to do with it, moisture has something to do with it, but the main factor is the shortening of the daylight hours, as Princhester said.
Formerly certified arborist checking in. Yes, deciduous trees change colors and shed their leaves all over the globe. Yes, temperature and water are a factor, but not a big one. The primary factor is the change in light. Most plants are extremely sensitive to these changes; small changes in light cycle will greatly effect their “behavior”.
BTW, evergreens don’t have to drop their leaves because they conserve their energy in other ways. But that’s another thread.
OK, I’ll start a new thread.
Please don’t start another thread.
We discussed in some detail the factors that stimulate trees to shed their leaves and what evolutionary pressures led to such a mechanism in a thread just two days ago.
In fact that thread was still active after this one was started so I assumed that the OP has read it and wanted specific information on what happens to trees in specific locales, not information what causes trees to drop their leaves.
Barbitu8 trees do not shed their leaves because the leaves lose chlorophyll. In fact exactly the opposite is true. The leaves lose chlorophyll as the plant attempts to scavenge some nutrients before the leaves are shed.
Ghanima water loss and temperature is the sole factor that prompts a number of species to drop their leaves. Those are much rarer stimuli in cold temperate and frigid regions but in the tropics and subtropics it’s about a 50:50 blend of trees that drop their leaves in response to water stress or temperature and those that respond to day length. As I said in the other thread I know of no species that are able to respond to more than one stimulus.
It should be kept in mind that, at least here in the South, the seasonal color is not like it is up north not because our leaves don’t change (they do) but because we don’t have as many deciduous trees. Lots of pine forest. This also means, however, that during the winter there are still lots of green trees - to me it gets very, very depressing up north where my mom’s family lives - it’s all gray, everywhere. Even if they didn’t have snow there wouldn’t be hardly anything green.
I don’t know where in SC you live, but near Charleston (which is just about as far south as you can go), there is plenty of beautiful autumn foliage. Red maples, especially, are very common here, and there are plenty of other maples, oaks, etc. Visit Magnolia Gardens or Caw-Caw County Park in November.
Yes, which is why the trees in SC change color and lose their leaves later.