hello, i finally took some photos today, of what i assume is a lovely japanese maple, at an office building near a friend's house. it has been a basic green since i first noticed it, earlier this year. we had a bit of a false summer, here in los angeles, a few weeks back, when our mild temperatures became noticeably warmer, and since then, this tree has begun coloring up. what i couldn't figure out, was if the rosy glow it acquired, was due to a flush of new growth or because it was reacting to prolonged, direct sunlight. i got as close as i could to it but the area i wanted to study was far too high, and extremely backlit, as the leaves i was trying to stare at, was between me and the sun. but then, as i started taking pictures of the lower branch, i noticed some of the leaves had very distinct patterns of color to them. in particular, the close-ups i'm posting are the bunch of leaves to the lower left of the tree, as they are the only ones i could reach. i remembered reading a post about "pleaching", and when i looked it up, i found mjh and mr. shep commenting on it, regarding bloodgoods and bloodgood-types. robert from mendocinomaples suggested in one thread, that discoloration of leaves may occur from a sudden change in the amount of sun exposure a plant receives, which totally makes sense. my question is, are these leaves discolored ( i can't tell what the leaves of the canopy look like since i can only see them from below ), or is this normal. i've no idea what type of maple this is, but i haven't seen any photos online or in a book as to the pattern of how this one is coloring up -- namely, from the center, which is why i thought "pleaching". but it also made me wonder if all japanese maples are subject to this type of sun bleaching, or, as in my case this year, if they receive too much sun, do the leaves just get dried up and turn brown. i know too little about maples to try to figure out what this most closely resembles, but i think it's so pretty. the few trees i have are all potted and come nowhere near being as dramatic in color. i'll post some more photos if i get to see it change some more before it drops it's leaves. thank you ! ^_^ n. musume
The leaves on this Maple show some pleaching as we called it in the nursery. It is much easier to see the dramatic effects on a red leaf. There is evidence of sun scald with the deadened tissue areas in some of the leaves also. The pleaching is essentially a superficial sun burning as the leaves are for the most part fine and will develop Fall colors later except for the scalded areas of the leaves. These leaves are by no means scorched as scorching entails a quick burn that desiccates the leaves and causes the leaves to shrivel up on us. All of the leaves from this late Summer photo are still on the tree as of right now. Jim
Pleaching is a training method, "the weaving together of the branches of a row of trees" (Brickell/Joyce). If anything, I would call the damage in the lower photo "bleaching".
Now we are splitting hairs but there is a difference between a bleached leaf and a pleached leaf. The pleached leaf can still carry out photosynthetic processes, albeit slowed in some areas of the leaf but the bleached leaf will render the cuticle seemingly dysfunctional as a protectant. Once the leaf becomes bleached here, then with the next sun burning it will result in a severe all over leaf scalding as opposed to small areas that may have been scalded after an intense pleaching. I am in effect comparing degrees of sun burning like a first degree burn to a second degree burn. One is much worse than the other for a leaf. Fading in color due to intensity of light without a burning is something entirely different. I am certainly not advocating leaf pleaching as being a standardized term but that is what we called it as opposed to a leaf bleaching. For us here we can see the difference in the degrees of sun burning more readily than cooler areas will and this does not apply solely to Maples either as other plants such as Gardenias, Azaleas, even Camellias can have and exhibit the differences in the two sun burns. A bleaching to us here is a result of a sun burn. You might see fading where you are instead. Jim
Big dictionary here only mentions interweaving and braiding for pleaching, nothing about color patterns, fading or the like. I thought there might be another usage I simply hadn't heard of.
Ron, we made up the term pleaching in the nursery for lack of a better term for it, if that is what you are after. The bleaching was much more serious for us as if we saw it as it was happening then we had to move the plants under shade cloth right now, whereas we left the plants out in the open if they were enduring a pleaching. Our Bloodgoods will pleach every year during the Summer. Too bad I do not have a photo of ours as others around here have seen the same thing happen to their Bloodgoods. The pleaching is worse on seedling Bloodgood grown around here and can eventually lead to a bleaching. San Francisco may not ever see the bleaching but can at times see their Maples pleach on them. Medford can see it also but not so much in Eugene. Jim
I'm with RonB on this one: Pleaching is from the French:Plassier; to Plait(weave). Something not commonly carried out in North America. Still carried out in Europe.i.e. live-staking Salix sp.(Willows); Sorbus sp.,(Ash),etc.. then weaving to create fences. Makes a great cheap fence. But then I'm a transplant, so my anglais use differs. I have created a "Pleached" fence at Finnies Farden, on the Riverview site, using French Willows.
I think there was already an existing term in place for what Jim & his associates came to call pleaching (among themselves, at least), but I don't remember it right now.
sun discoloration of leaves thank you so much, ron b. and mr. shep, for the educational replies ! ^_^ i will have to re-read mr. shep's explanation of the differences between "pleaching" and bleaching and even scalding vs. sunburn vs scorching. it's all a bit confusing for me as i don't think i've experienced anything but a sad amount of plain, "dried up brown leaves", on most of my trees. i still have to understand how "desiccation" fits into all of this. perhaps when my plants get a bit stronger and better established in their containers, they will be able to withstand the intensity of the sun to a better degree, and give me examples of all of the above. speaking of the strength of leaves, i was quite surprised at how well both my higasayama ( i have doubts about the validity of this one ) and chishio improved have held up; this being the first summer i've had them both. i'm also trying to figure out the whole role of photosynthesis and chlorophyll in both red and green leaves but i'm a bit overwhelmed with information and too full of half-formed questions. i will try to post photos of what the non-sun-discolored leaves end up looking like as they go through their fall colors, just to compare the differences. thank you both again, for all your help ! ^_^ n. musume
perhaps when my plants get a bit stronger and better established in their containers, they will be able to withstand the intensity of the sun to a better degree, and give me examples of all of the above. You do not want to witness all of the factors such as the pleaching, bleaching, sun scald, scorch as some are normal for us here in warmer climates and some can be trouble. There is a term for the pleaching as Ron stated but we could not ever think of it as for years people lumped what we called pleaching in with leaf bleaching and we learned first hand they are not the same at all in how the plant responds to both. One is a normal condition but the other is not normal and can lead to a real problem later if we are not careful. Sun scald can be normal also and can be left alone and considered normal for here also but scorch is all together different in that with scald the leaf can still function but with scorch the leaf is lost. We do not get twig die back from sun scald but we can get twig and other die back as a result from a severe leaf scorch. You picked out a good tree to monitor as it is not a typical green seedling. Trees that develop an array of colors starting in Autumn are fascinating to me. I like the ones that produce a variety of Fall colors better than the Maples that produce an intense solid color such as a brilliant crimson red but that is just my preference. Jim
wow ! thank you so much for breaking it all down for me, mr. shep ! and especially for pointing out, that burning, scalding and scorching, are all essentially, examples of sun damage, and as such, are not conditions to aspire to. >_< i guess in my enthusiasm for wanting to see all the pretty colors, i totally forgot that the change in color at this time of year, is basically, the death of a leaf, and, as you added, in more severe cases, the death of perhaps the twigs themselves. i can really get distracted to the point of counter-productive thinking when i'm trying to study these trees . . . thank you again for taking the time to reply ! ^_^ n. musume
So as I follow..."pleaching" as described by jim is not as severe as scalding. Where does the term "bronzing" fit into this discussion? Attached is an Okagami in August with what I call "bronzing".
Robert, O kagami bronzes out naturally during the year. This is a normal color function for this Maple. We are more apt to see the bronzing on the lower leaves and the leaves in the middle of the tree that do not get as much sunlight as the rest of the leaves. Bronzing as a result of too much sun or hot direct sun is shown on the last surviving example of the old original tissue culture Maples I showed a photo of. In this case the leaf will turn the bronze color we are seeing but that to us in the nursery was a pleach. If we see this condition evolve the bronzed areas will become lighter in color more towards the center of the leaf later and this to us was the pleaching, much more so than a bleachng as the leaf technically has not been damaged yet. Not like a bleaching that will injure the cuticle which makes the leaf susceptible to a quick and irreparable burn much sooner than later. Jim
hello, these photos were taken on nov 20. it was still mid 80's during the days and mid 60's during the nights. alot of the leaves have browned and shriveled up, but the shoots they are on, are a pretty, soft bright green color and are very healthy. i can see how the obviously pleached portion of some leaves are still apparent through their fall coloring. one shot is of a group of pumpkin colored leaves that was protected from the afternoon sun by the canopy above it. you can also see a couple of bright yellow leaves toward the bottom right edge of frame in the same photo. i love the range of color this maple is showing. i wonder how much of it is due to the extreme stress of pleached leaves. i also hope the huge scar on it's trunk, that you can see in some of the photos, won't be affecting it's health. i have a couple more photos that i will post that were taken more recently. ^_^ n. musume
ok, these last two were taken on dec. 6, and what is left of the foliage, is starting to go a brilliant ( almost flourescent when seen at close quarters ) vermillion. i ran out of batteries before i could take a shot of the entire tree. it's gotten 15 to 20 degrees cooler for over a week now, and i'm wondering how that's affecting the color. i will post photos in the spring time when it leafs out in case any of you are interested, and thank you all again, for your replies ! ^_^ n. musume
