I've got a situation that I just haven't seen before and was wondering if anyone has had a similar experience. I planted an a.p. Atropurpureum (supposedly a Bloodgood) on the north side of my garage about three summers ago and he has been doing very well. He has a caliper of about 2" and is about 12' tall. On Saturday, I noticed that all the leaves on this tree has wilted and were in the process of crisping up. This event had to have occured in the matter of a couple of days. We've just finished up one of the hottest July's on record, if not the hottest, so my initial thought was that the drip system on this guy had failed and he was out of water. So, I pulled back the mulch and landcape fabric and pulled soil cores out near the drip line with a small shovel. It's not dry. Nor does it seem to be too wet. I've got really heavy soil, so the latter can be as damaging as the former. But, I believe the moisture content around this tree is about right. None of my other japanese maples are looking like this. Not even related specimens like Fireglow and Moonfire. And, I've got a small Inabe Shidare (1" caliper, 3' tall)around the corner on the west side that's getting exactly the same portion of water. Oh, sure -- there's a considerable amount of leaf scorch this year, but the Bloodgood's symtoms are not a scorch -- more like a melt-down. The only thing I had noticed that was different this year was that the Bloodgood's leaves had really gone to an orange, bleached-out look this summer. If I thought it needed more water, I'd water it. If I thought it needed to dry out -- well that wouldn't take much right now. But, I'm at a loss as to what I should do, so my current strategy is to watch, wait, and hope for the best. Anybody got any other ideas? Bryan
Unfortunately, the sun's the problem. Even though this species is better than most acers in the sun (Japanese maples like light shade best), this year may just have stressed the heck out of it. At this point if you're sure the soil's not dry, I'd clip off as many leaves as possible - you'll get a new crop come in a bit smaller in size - and cross your fingers. It should have been done a month ago, but... BTW, maple roots do grow wide and shallow, are you sure it has enough room to do so near that garage?
Bryan, I've had some email discussions with other maple enthusiasts over the past 24 hours and we are all in the same boat. Here in NJ, we had 95+ temps for four days strait and despite my attemts to keep water on my trees, I had an established 'Katsura' and "kinran' completely defoliate. I think that what can make you a great grower of Japanese Maples (i.e. healthy trees, ample fertilizer, water, and care) can haunt you when the weather shows extremes. One way or the other, Acer palmatums are pretty hardy trees and they should snap out of it next year. My only fear is that my completely defoliated 'Kinran' will push new buds too late in the year and get zaped by frost (possibly a death sentence). But Acer palmatums are usually "smart" enough to only emerge secondary flushes on their terminal buds and not all of them, saving hope for next year. best of luck. Brian
Hmmm, this is interesting. My newly planted maple did this at the beginning of July and now I'm seeing all these posts of similar situations. I'm beginning to think it is our extraordinary weather this summer that is causing the "shock" to the JMs. Our trees (for those of us who don't live in hot climates) probably aren't used to dealing with the kind of heat we've been getting. Mine, being newly planted, collapsed fast. An arborist finally contacted me and advised me to remove the dried up leaves if they don't fall off on their own. I did this yesterday... they broke right off in my hands. Hopefully the tree will survive. Keep us posted on what happens to yours and I'll do the same. I've been checking the soil for moisture and watering only when it starts to dry out. Can you post a picture of your tree? My tree's leaves turned an orangey/red a few days before they wilted. It only took about 5-6 days for the leaves to wilt and curl on the whole tree. I received a lot of good insights from the people on this forum. If you'd like to read them see the thread titled, "Did my Japanese maple catch verticillium?"
I hear ya, Brian. We tied a record with nine straight days of over 100 degrees in July. This tree had fared well the last two summers. I guess it was just too much for it this year. What's interesting is that I have about 40 young grafts and seedlings in one to five-gallon nursery pots that are simply heeled in to try and keep the roots cool. They're nestled up against the north side of a 6-foot fence, but still get more sun than I would really like -- probably as much as the Bloodgood. Even so, none of them look that tough right now. Actually, I'm quite pleased with the way they've dealt with this summer's heat. I would have thought that the pots would have gone before a planted, established tree. Bryan
Bryan, My hunch is that your tree underwent an additional stress, like a change in the watering schedule (i.e.: one or two days without water ) while the temperature was unusually high for your area. Over here in Western Europe we've also had a pretty hot summer. In my garden highs have been in the high nineties/ low hundreds during the last 3 weeks of July; as I say, the garden was in a 'survival mode'. Gomero
Bryan, I was just wondering if the 'Bloodgood' was receiving additional day-after-day reflected heat from the garage, foundation, or any rocks nearby?
Re: Heat Stroke? Gomero, You may be on to something, here. I did change the watering routine in early July from what I have done in prior years, but in an opposite way to your suggestion. I've always set my system to drip for an hour every third day. But, I changed that to 20 minutes every day this summer. I was afraid that some of the plants and shrubs in this particular landscape zone might be suffering from things drying out too much between waterings. While there was no net change in total water input, I wonder if the change in frequency and duration is driving the negative effect. Do you suppose this tree could be asphyxiating from a lack of air in the root zone (staying a little too moist and not having an opportunity to dry out in my heavy soil)? Or, do you suppose that the less frequent waterings might not be driving moisture deep enough? Now that I contemplate this further, doesn't the size of a tree dictate its water needs? Wouldn't a tree that's eight years old need more water to survive than it did when it was four years old? Would it follow that I need to increase the size or number of drip emiters as my trees age? Maybe my soil-probing techniques have not been adequate for truly evaluating the moisture situation in this tree's root zone. Anyone have any suggestions for how I should be doing this and what I should be looking for? Bryan
Bryan, I would guess that the daily watering was the cause of your problems. Trees need periods of moisture, mixed with dry down periods, to grow and flourish. In fact in the nursery, optimum/maximum growth conditions occur when you take trees to nearly leaf wilt dryness before watering them. Overwatering will only increase the likelyhood of root rot problems, plus your trees will not produce vigorous roots (since they won't need to with daily waterings). Additionally, as trees mature their water needs are less, not more, because they should have sufficient healthy roots deep in the soil to gather the water they'll need. Your better off laying a dripping hose at the base of an established Acer palmatum overnight once a month during the summer, than watering it daily or even weekly. Get the water down deep and entice the tree to reach for it with it's root system. Even with the lightest soil mixture in containers and a preventative diet of fungicide and insecticed, I would not water any of my maples daily. Along with potentially drowning the root system, your inviting a whole cast of pathogens, and you are not pushing the tree to develop roots on its own. Hope this helps. Brian
My understanding of these plants is that any changes to their normal environment, even for the better, generate a stress. When several stresses add up then the tree is 'unhappy' and it shows it. A disease or parasite being also a stress. Regarding watering, this is something each one has to figure out taking into account local climate, soil type and, foremost, plant behaviour. To me it is a trial-and-error approach. I find maples to be quite adaptable plants, as long as you don't change their environment; that's why I like to place them in their final position as early as possible. My garden is also heavy clay (sloped though) which is heavily mulched every year; there are maples all over and some get 20 min drip watering each day and some less than that. In fact well establish plants can go for seeral weeks without any water at all which is what Bryan hints whan he talks about watering needs vs. plant size. Gomero
Check out the article entitled When Trees Drop Their Leaves or Develop Early Fall Color by Doris Taylor at the Morton Arboretum: http://www.mortonarboretumphc.org/feature%20articles/Plant%20Physiology/When%20Trees%20Drop%20Their%20Leaves%20or%20Develop%20Early%20Fall%20Color%20%20August%202002.pdf.
How long has that decay and damage been present on the trunk (reference your 2nd photo)? I would think that that would represent a key player in your premature loss.
Re: Heat Stroke? It's one of my suspicions as well. That's the primary reason I posted these pictures. The tree's rapid demise seems to suggest a total breech in its ability to transfer water from the root system to upper extremities. Considering the shape the bark is in, this doesn't seem such a remote possibility. I first noticed some minor bark problems on this tree about a year ago. What caused them and what, if anything, could have been done to prevent their progression is an unknown for me. It would be nice to know if this was the result of a pathogen or simply a genetic defect or environmental issue -- I'm a bit leery about planting any sort of replacement shrub or tree is this area at this point in time.
