|The Colors of Oaks
||[Dec. 7th, 2015|11:29 pm]
European Oaks, I've been told, do not change color in the fall and winter. Some North American oaks develop brilliant color, and among these are several species of oak that grow in central Texas. They change late--later now than fifteen years ago, pushing the ones in our yard to late November and early December, instead of early -mid November. Years back, the oak leaves might have blown off by Thanksgiving; now they're just starting to turn then. But this year, this week, they've been developing color.
What makes oaks very different from other deciduous trees in terms of the effect is their leathery-shiny surface, and the variability--even on one tree--in the way the leaves turn. Sunlight glints off the leaves as well as penetrating them, so the tree sparkles and shimmers with color (very unlike the fiery glow of a sugar maple in New England, which has broader, thinner, and matte leaves, not glossy at all.
These were photographed with the sun behind me, showing the "shine" on the surface and the variatility of the leaf change. These are all still on the tree--one branch of one tree. This particular tree, when fully changed, ranges from a medium to a dark red with a few yellow and orange leaves.
Seen from behind, with the sun coming through, there's another effect:
This red oak is almost touching a Caddo Maple on the right; this oak develops oranges and yellows and some light/medium reds; the maple develops a clear yellow following lime green (dark green summer foliage.)
same tree as above
The front yard largest red oak is the only one we bought (a gift from my mother.) The other red oaks we have were planted as acorns dropped from trees we spotted out in the country--and then visited at the right time to pick up fresh acorns and plant them. We've also planted bur oak acorns--bur oaks develop only a rich gold color (in some years no color) but have the advantage of being disease and drought resistant. They were once known as "prairie oak" and formed the famous "oak openings" that Native Americans and pioneers both liked to camp in.
Here are some trees "front-lit" by the sun in various colors.
Orange-gold in front, red behind A different mostly red, with still-green smaller one behind
These trees are stunning if you're standing under them or with the sun on the other side.
So if only people would quit tearing down "brush" and let the young oaks grow (or plant the acorns) we'd have plenty of fall color around here. Oaks grow slowly until they get their tap roots down into a moisture source (supplemental water for the first few summers really helps) but most of these oaks are only 20-15 years old. They don't show a lot of color as young trees, usually, but show more color every year as they reach maturity and start producing acorns. This year we had a huge crop of acorns.
It's an "acorn year" here, too. I wonder if they all produce at once, all over the world.
I thought it was rain at the right time after drought, but could sure be wrong.
I think scientists have not figured it out yet, from what I've read!
(small correction: they turn golden/brown, but never red. Red is for Maples in all combinations)
I must get a few pictures up, once this edit is off my desk...
Our (UK just S of London) oak tree has turned yellow/brown and is just starting to lose its leaves. very late this year. Other trees (Ash, Walnut, Birch, Apple are all but bare, the oak is still mostly leaf though now mostly brown. Our oaks don't do great colours. Not such a good acorn year for us, last year was huge.
The colour in that top picture is not golden or brown, it is red.
The oaks on the hillside we can see from the back of our house (UK, near Manchester)are bare now, they turn yellow then a golden brown. When the low evening light hits them they glow golden, it's one of the joys of living here.
The bur oaks turn brown some years, and yellow (but not a bright yellow, a soft yellow) and then brown. In fact, one of the back yard ones has turned yellow since yesterday, so I should go take a picture of it. One of them turns a brighter yellow than the other. (more acorn-started trees.)
Last year was the super-plenty acorn year in western Lower Michigan. The guy who cuts grass in my neighborhood said he'd _never_ seen so many acorns, and this past summer there were still many, many on the ground, unpleasant to walk across as one's feet and ankles rolled; sort of like walking on round pebbles scattered on a sidewalk.
I read recently that while European trees all turn yellow, orange and brown (and believe me, they can look spectacular when they do!), they don't turn red as trees of American origin do (we have some imports and they, too, look lovely), since they merely lose their chlorophyll, while American trees add some kind of red toxin to their leaves. I am not sure quite why this is - the article, which I no longer have the reference to, did explain, but I have forgotten.
Beautiful! My favourite trees, though I don't commonly see them here in Australia.
The trees hereabouts [Atlanta] have mostly gotten naked before the leaves even turned, the last couple of years. There've been individual splots of color, but not whole trees, like we normally get. It's also been a banner year for acorns, & the squirrels & bluejays have been woefully slack, so there's lots of that slippery cobblestone feeling to go around.
I love these photos. Oaks are lovely trees. Fascinating information about them. Thanks for posting.