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vjpj

Japanese Maple problem leaves

vjpj
17 years ago

We have a Japanese Maple, not sure of the variety, but the leaves look like the picture on the maple forum page. The tree is about 18 years old and has grown to about 8 ft across and about 3-4 ft tall. The tree appears to be healthy and grows each year, but in the middle of the summer most of the leaves turn light brown at their ends (appear dried out) and in the fall instead of turning a nice red, most of the leaves continue to have a burned on the ends look and even the portion of the leaf that is not "burned", does not turn red. Some of the leaves on the lower portion of the tree, do not get the burned ends and do turn red. But overall, the tree has a disappointing look to it for much of the year compared to others in our area.

Being next to a lawn that gets well-watered, we think the tree is getting sufficient water. And it is sure getting a lot of water now... here in Seattle. The ground is sloped steeply away from the tree on the side opposite from the lawn and the slope is covered with ivy.

Any ideas on what's wrong with the tree and/or how we can get the tree to look the way we think it should, would be appreciated.

Comments (18)

  • gardengal48 (PNW Z8/9)
    17 years ago
    last modified: 9 years ago

    Your tree is a red leaf dissectum - lots of possible cultivars - and what you describe is classic drought stress. It may be pretty wet now in our typical rainy November, but summers here are routinely very dry. And unless you are deep watering the tree directly and not relying on overspray from the lawn, the tree is not getting enough summer moisture. This could be compounded both by the slope, which encourages drainage and could facilitate water just flowing off the bank rather than soaking in, as well as the ivy groundcovering. Ivy (which is a huge no-no in our area, btw) will easily outcompete the maple for soil moisture and nutrients.

    Can you describe how you are watering - how long and how often, both the lawn and the tree?

  • vjpj
    Original Author
    17 years ago
    last modified: 9 years ago

    Thanks Gardengal48 for your informative response. I think you could be correct in your analysis. If true, what threw us off, is that the leaves turn brown at the ends so early in the season, maybe in June, before the rainy season even ends.

    To answer your question, we water the lawn about 7 minutes per day, supplementing with hand watering when it gets really hot and dry.

    Now you tell us about the ivy :). We planted it when we built the house 22 yrs. ago to prevent erosion of the steep hillside. It worked for that purpose, but have been trying to figure out how to keep it under control or get rid of it for many years now.

  • gardengal48 (PNW Z8/9)
    17 years ago
    last modified: 9 years ago

    Whoa!! You need to rethink your watering regime, even for the lawn. You are wasting far more than any plants will benefit from - 65% of pop-up irrigation is evaporated before it even hits the ground. In our climate, lawns need an inch per week in summer to maintain a good green color and proper growth, preferrably all at once or at the most, broken into 2 sessions. That typically means running your irrigation system for a minimum of 25-35 minutes twice a week. Anything less is just a waste of money and a rather precious natural resource. And the maple would be happiest with a deep, slow watering every 10-14 days. You want to make sure the water penetrates well down into the root zone, about 8 inches. A soaker hose is ideal.

    As to the ivy, I'd suggest removing it if you can and replacing with a more environmentally friendly, less invasive groundcover. If not, keep it well trimmed and do not allow the development of adult foliage or flowers. I'd hate to tell you what might be residing underneath all that obscuring foliage but they rhyme with "cats" and they don't meow :-(

  • vjpj
    Original Author
    17 years ago
    last modified: 9 years ago

    Thanks again for your input. By my calculation 7 min/day is less water than 25-35 min twice a week? Our sprinkler heads are quite close to the ground and water in the evening, so doubt evaporation (before hitting the ground) is any significant factor. Also, lawn is quite small and even with 7 min, water sometimes starts to run off the lawn, into the maple and down into the ivy. With 25 min think most would run down the hill and do the most "good" for the ivy. Plus, in mid-summer when it gets hot, the lawn dries so much during the day, it (still) sometimes begins to turn brown and needs additional watering. Afraid if it went 3 days (or worse 7) without water, wouldn't have to water any more, it'd be all brown.

    Yep, seen the long tailed critters you referred to, also seen them in the au-naturale green jungle in the vacant lot south of us and across the street.

    Will try watering maple deeply next year, think you still could be correct and that will alleviate its problem.

  • vjpj
    Original Author
    17 years ago
    last modified: 9 years ago

    Have aerated religiously.

    Don't think you understand how much water would be put on only 120 sq ft of lawn, if I watered for half an hour. It would almost certainly not only run off the top (which is not flat, but at a shallow angle), but also out of the side and down the hill. I will try watering less often for a little longer, except when it's really hot, when I'm almost certain, it would result in the lawn getting burned to crisp.

    When I was a kid I lived in VA, where the summers were admitted hotter (but not drier). Remember my father noticing that the only lawn around that stayed green, was the one where the kids played with the hose every single day.

    BTW- Not new to this game, had the lawn for 20 yrs. with mostly good results, while most lawns in our area by midsummer seemed to be partially or completely burned.

    Not trying to get into a contest here. But, I'm a retired Chem engineer and can assure you that in the evening, when the relatively humidity is high, the % of cool water that will evaporate, while dropping a few inches is diminimus.

    Obviously, if you water 30 minutes twice a week, you'll get more evaporation (during the watering), than watering for 7 times for 7 min.

  • gardengal48 (PNW Z8/9)
    17 years ago
    last modified: 9 years ago

    And I don't wish to argue with you, either - I am simply attempting to share my years of experience as a professional horticulturist, combined with the commonly accepted scientific basis behind the study of plant needs and smart watering practices.

    while most lawns in our area by midsummer seemed to be partially or completely burned.

    Fallacy #1: these lawns are not "burned" - merely dormant. In the PNW lawns are blends of cool season grasses. They naturally want to go dormant in the heat and dryness of midsummer and many folks allow them to do so in the spirit of water conservation. While they may appear "burned", the turf grasses are simply resting until cooler temperatures and fall rains return. These conditions, as well as the odd summer watering, will green them up extremely rapidly, sometimes as fast as just a couple of days. Only one inch of water per month during our dry summers is necessary to keep dormant lawns alive and healthy.

    in the evening, when the relatively humidity is high, the % of cool water that will evaporate, while dropping a few inches is diminimus.

    Fallacy #2. While it is certainly true that watering in evening will reduce evaporation - the less sun and heat present, the less evaporation occurs - it is not a good idea. Evening is a poor time to water, specially lawns. Water remaining on grass or foliage for an extended period of time - like overnight - increases the incidence of fungal problems. Most fungi, especially those associated with turf grasses, require damp conditions and high humidity to flourish. Watering 7 days a week for a short period of time during the evenings is encouraging more in the growth of pathogenic fungal organisms than it is supplying adequate moisture to the soil and its inhabitants or to plant roots. Relative humidity is at its highest point at dawn or right before daybreak, therefore evaporation is lowest at this time as well. And timing your system to water at dawn will reduce the amount moisture that remains present, as the sun will rapidly dry it up, reducing the likelihood of developing fungal problems.

    You will not be decreasing the amount of evaporation by extending your watering duration but reducing the frequency, but neither will you be increasing it if you water in the very early morning. Unfortunately, inground irrigations systems at best are only 60% efficient, but they still deliver a higher percentage of water to the plant roots than do sprinklers or handheld watering devices. And there really isn't a better way of watering lawns in particular - trees and shrubs, yes, but not for lawns.

    In addition to reprogramming your system to come on at dawn and only twice a week, I'd also suggest you recalibrate to ensure you are not applying too much all at once. You should be generating no more than 1/2" per 30 minute period (you can do the tuna can test to measure this). More than that will increase the tendency for run-off - there is only so much water the lawn and soil can absorb in any single session, yet still have the water percolate down sufficiently to be of value. If you have clay soils that are so common to parts of this area, it may be necessary to double up the sessions as well - that is, run the system for 15 minutes, stop, wait for 15-30 minutes and run another 15 minutes. This method will still derive the same benefits of the longer duration but reduce the run-off that may naturally occur with heavier clay soils.

    And finally, a note on aerating and soil compaction. Unless you are doing core aerating - removal of a 3" plug of soil - twice a year, you really are not accomplishing anything. After aerating is an excellent time to apply a thin (1/4" or so) layer of compost to the lawn. This will improve the soil structure as it works its way down into the voids left by aeration, loosening a heavier soil, increasing porosity and reducing compaction. It also will reduce the need for additional fertilization as it is a low grade, organic nutrient source. Leave the core plugs in place, too. While not wildly attractive, they will be quickly chewed up by mowing and again, will return organic matter down onto the soil. And you probably need to dethatch as well. Thatch build-up will occur rapidly with shallow watering practices and frequent fertilization and this too can prevent water penetration and increase run-off.

    I hope you take all this in the spirit in which it is offered and find it helpful. And that I have successfuly addressed your concerns about your maple, which was the whole point of this discussion :-) It has been my experience in my professional career that plant water needs and irrigation is a rather misundersood issue and my intent is only to educate and be of help.

    Happy Thanksgiving!

  • vjpj
    Original Author
    17 years ago
    last modified: 9 years ago

    I will say once more that I appreciate your input (all the time you've spent on these posts) and will most certainly take it into account.

    But, can't help but comment that when you claim to be an expert, then right off the bat make an unequivocal statement like "You are wasting far more than any plants will benefit from - 65% of pop-up irrigation is evaporated before it even hits the ground." Which (at least in my case) I remain certain is extremely overstated (to be polite), it reduces your credibility. Makes me wonder where such a figure came from? You might want to check your source. If based on actual data, must have been recorded in 100+ deg sunlight with a strong wind blowing. Used to own a pear orchard in Eastern Washington and don't believe, even there, our evaporation losses (before hitting the ground) were anywhere near 65%.

    Re: "Fallacy #1: these lawns are not "burned" - merely dormant." I agree these lawns begin to turn green again, when it starts to rain... more proof that more water helps, not hurts the lawn. But who wants a brown lawn all summer? This time a year the lawn, whatever color, isn't of a lot of use. I manage to keep our small piece of lawn green all summer with less water than you (first) recommended.

    Re: "I'd also suggest you recalibrate to ensure you are not applying too much all at once." Wish I could, problem is, if I reduce the pressure, the sprinklers won't pop up.

    BTW- I'm almost certain, we do far more toward water conservation than most. Water fruit trees and a small veg garden with soakers, a few shrubs with bubblers and don't water the ivy at all. We use water saved from showers for the washing machine and collect rain water from a down spout for supplemental and house plant watering. This was confirmed, when an couple of years ago, Seattle Utilities came to verify that our meter was working properly, because they doubted we were using as little water as we do.

    Thanks again for your theories about our problem maple and hope you have a good Thanksgiving too.

  • gardengal48 (PNW Z8/9)
    17 years ago
    last modified: 9 years ago

    You know, when folks go out of their way to answer questions and provide information and then get slapped down because whatever was offered doesn't quite jive with the requester's own opinion, it kind of makes the whole operation pointless, don't you think?

    FWIW, I never claimed to be an expert, just someone who has spent a great deal of time and study (as part of both my education and personal and career development) researching these issues. If you don't care for what I have to offer, that is certainly your prerogative, but then YOU do the research if you even bother to want to learn. I'm sure you will find out that what I had to share is supported wholeheartedly by scores of turf care and water conservation websites and even a few of the more environmentally responsible irrigation system sites as well. Pop-up or spray irrigations systems are notoriously inefficient, wasting 50-80% of the water they emit, either through improper directional setting, timing, allowing run-off and yes, through a considerable amount of evaporation. Actual figures figures vary depending on specific source and environmental conditions and I picked a figure somewhere in the middle. So sue me.

    You go ahead and do whatever it is you want to do. I'm done.

  • vjpj
    Original Author
    17 years ago
    last modified: 9 years ago

    If you made the statement, "Pop-up or spray irrigations systems are notoriously inefficient, wasting 50-80% of the water they emit, either through improper directional setting, timing, allowing run-off and yes, through a considerable amount of evaporation", in the first place, I might well have let it go.

    Instead you stated as fact, "65% of pop-up irrigation is evaporated before it even hits the ground", which I knew to be incorrect. That got us going on the wrong foot. Sorry you feel that by my disputing this you got "slapping down", that was not intended.

    At this point I too feel I have better things to do. If you'd like to have the last word, feel free, I won't respond again.

  • myersphcf
    17 years ago
    last modified: 9 years ago

    I wrote this last night before the last post and then decided it wasn't worth posting ...but now I decided it was worth doing so in the hopes that other at least think before they post and since both parties are "done" with this thread I get the last word ;>)

    I agree wiith GG...I don't know ANYTHING about auto lawn sprinler systems and corresponding water %.... but when a person asks for help and another person is nice enough to answer I think it behooves the askee to thank them and either use the info or not and move on ...not argue with them. As a person who does try to answer folks with questions it is VERY irritating to have tried my best to answer and then have the askee poo poo my answer as if they really weren't interested in my imput or for that matter anyones imput or any answers in the first place but just wanted to post or let the world know about their problem ( I am not saying that what has happened here but the askee doesn't seem to really want to hear answers that don't jibe with their preconcieved notions...so why ask??). I hope your tree becomes what you want it to be and you find out what is wrong with it. David

  • botann
    17 years ago
    last modified: 9 years ago

    I think you need to get a soil profile of your lawn area to see what you are dealing with. Dig up a slice and look at it. Go at least 8 inches down. Use a pitchfork to aerate deeper than you have. Also aerate the soil under and around the maple. It's a little late in the season to find out how dry the root area for the lawn really was this summer, but GardenGal48 has the right answers as far as I see. One other thought. Have you used a broad leafed weed killer on your lawn? It could have leached down to your maple making it look sick. The symptoms, though, point out lack of water as being the culprit.

  • leslie_4plants
    17 years ago
    last modified: 9 years ago

    So far most of the listing sound very much like my problems.
    I have a 17 year old green leaf Japanese Maple tree. The leafs turn brown
    on the edges and drop starting about a month after they come out.
    The few leaves that are left by the next month, have a totally burned look.
    Next problem:
    The bark is spitting and has light green or white spotting.
    I have had people to come out to take a look at it, but they seem to know no more than I do.
    Please help me save this tree. I love it and would hate to see it die.

    Thanks, LP
    P.S. I tried to add pictures but message center would not take them.

  • jumbojimmy
    17 years ago
    last modified: 9 years ago

    i too have a coral bark sango kaku Japanese maple that is experiencing leave burnt during the summer period.

    Having grown this maple tree for about 4 years now...the most likely factor is the sun and the wind problem.
    You see, in Spring, the leaves were so lushest and green...but when summer comes they compleletly changed miserably. I went to a nursery, and they have their maples shade covered.

    I read from somewhere that dissectum like your burgendy one requires a shady position and doesn't tolerate full sun quite well. The only exception is seiryu, that can tolerate some sun.

    It depends how small your maple is...only mature ones can handle more sun better than the younger ones.

  • leslie_4plants
    17 years ago
    last modified: 9 years ago

    Is there a way to send pictures of problem plants to the form?

  • jumbojimmy
    17 years ago
    last modified: 9 years ago

    eslie_4plants : another member named, cupshaped_rose told me to post pictures here u have to:

    1)Create a free account at Photobucket:

    http://photobucket.com/register.php?link=topmenu

    (cut and paste the link above to your adressbar)

    2)login to your new photobucket account

    http://photobucket.com/login.php

    (cut and paste the link above to your adressbar)

    3)upload pictures from your picture files

    4)when you want to post a picture in a post to this forum you have to highlight/Copy and paste the line underneath your uploaded picture that says HTML TAG (there are 3 lines underneath your uploaded picture (URL, TAG, Code...choose tag) to your post:

    5) when you click Preview message you can see if your picture has been posted in the message

    Like this:

    Jimmys Abricot-coloured Heritage.

    ----------------------------------------------------

    I find setting up your own "blog" more easy than the above method because sometimes the photos you put in photobucket doesn't appear in different browsers.

    U can set up a free website or a "blog" as it is often call in:

    http://www.blogger.com/start

    and follow the 3 simple steps.

    Once done come back here and type down your own website name in here. say for instance, I named my website, "www.myfavoriteplants.blogspot.com/ and under "name of the link" I wrote: "Jimmy's favorite plants".

  • wbmacon
    13 years ago
    last modified: 9 years ago

    I have two dissectum leaf maples in my yard. They have been planted in the same location for approximately 9 years. This year we had an extremely harsh winter (multiple days below 30 degrees). They budded as normal in the spring and began to leaf out. Many of the leaves never progressed beyond the bud stage. Many of the leaves are small and almost bud like some are normal size. We also mulched the trees in early spring with a cypress mulch. Any ideas what the issue might be? Thanks for the help.

  • sue
    13 years ago
    last modified: 9 years ago

    A couple of people have asked about the light green spots on the trunk of the Jap. maple, and the leaves are burning on the edges and falling off. Does anyone know what the problem is? How to take care of the problem? Mine is doing that this year, I don't want to lose this beautiful tree.

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