hi here is a pic oj my acer palmatum http://img222.imageshack.us/my.php?image=1454547op2.jpg http://img83.imageshack.us/my.php?image=1454542gt6.jpg i fear it is verticilium i live in france in the south and it is really hot for 2 monthes the tree is watered carefully it is really important for me to have your point of view because it is ner others acers and i really want to avoid massive dying i also suspect over fertilization combined with heat thanks to all
Re: Did my *** Maple catch verticillium??? bis! It's more likely they just have 'sunburn', and should really be in light shade if you can manage it. They also need fast draining sandy soil, not a 'flower bed' (if that's where they might be), and shouldn't be watered until they need it - not to a schedule, but when the top layer of soil is dry - they're a little more like pine trees in that respect than perennials.
Re: Did my *** Maple catch verticillium??? bis! thanks for the advice the plant is located in a mid shaded place, so i am a bit surprised if it is sunburn this is a sandy and fast draining soil can it be a "heat shock"? what about overfertilization? does it look like that? waht about a fungus? thanks again for your answer i love this forum!!
Re: Did my *** Maple catch verticillium??? bis! Hello. As regards overfertilization: if your tree is in the ground there is probably no need for fertilization - especially do not add nitrogen. Have the soil tested. I don't fertilize the maples I have planted in the ground (of course I mulch them, which counts). I only fertilize older maples in pots, but very little. As regards verticillium, here is a thread that might of interest. http://www.botanicalgarden.ubc.ca/forums/showthread.php?t=8751 If you can take a sample of leaves to a lab - where I live the agricultural ministery provides that service for free, may be it's the same in France? (same for the soil tests)- that way you can narrow down the list of culprits... Schusch
Re: Did my *** Maple catch verticillium??? bis! Luxembourg is probably a rich country ;o)) In France not only they do not do it for free, I think they would not do it even if you wanted to pay for it, LOL Gomero
Re: Did my *** Maple catch verticillium??? bis! LOL is right! I hate to imagine even asking here! That said if anyone knows about any such service in France, I'd love to know about it... :) Doesn't look like verticillium to me, though I'm certainly no expert on it. I'm guessing the "canicule" has done a job, as with so many of our plants here. Wait and hope. -E
Re: Did my *** Maple catch verticillium??? bis! Gomero :) but seriously... it makes sense to offer this service since it helps keep track of diseases, etc, so may be - may be - they have a similar service in France, even for a fee? Otherwise certain stores do it for you - I've seen the Truffaut chain offer soil tests, for instance. Schusch
Re: Did my *** Maple catch verticillium??? bis! No, that is not a sign of Verticillium yet. We see this condition here all the time when we do not give the plant enough water or the plant cannot pump water fast enough to offset the leaf transpiration loss. We will see the sun scald on the uppermost leaves as the plant does what it can to protect the lower leaves from intense heat, direct sun and hot winds. With a sun scorch we will see the leaves shrivel up turn brown and the tips of the twigs will wilt and we will see some twig and perhaps even branch damage soon afterwards in comparison to a sun scald. Placing the tree in shade may have an effect on making the tree look better but there is a price for doing that in that the tree will not adapt to your conditions should you be faced with another similar heat wave or a more intense heat cycle that your trees may endure in the future. It is better to have the tree burn in the hot sun now rather than see it burn some in shade as once the leaves drop while in sun we will have new growth that will be more heat and sun resistant to the elements that caused these leaves to scald. Where you are you do not get the growth cycles we can get here. In our Tsuma gaki we are now into our fourth growth spurt. Sure, the top leaves look like they have been fire roasted with many bare twigs but we also do not have any noticeable twig damage and thus we have new leaves starting to emerge from the bare tops where the third growth spurt leaves were and had been severely sun pleached at first, then flat out scalded later, fell off and now we have new leaves starting to come back on. The tree will have new growth showing on the lower portions of the plant before the uppermost growth comes back in intense weather. They also need fast draining sandy soil. No, this information does not pertain to warm growing areas. Water goes right through sand and no matter even if we super saturate our container plants we will still see scalding going on no matter how much we water. We want water holding capacity in our soil mediums and sand will not hold water. Sand is used for aiding drainage but will not help much otherwise. Even a heavy clay with ample humus in the mix will be far superior than a sandy composition will be for container Maples. A high percentage sand in the soil mix will almost be a death sentence for container plants here unless we water the plants multiple times a day, even when grown under 50% shade cloth. Silt is far better to have as our prevalent soil in our soil medium mixes. Silt retains and holds moisture for a long period of time whereas sand will hold moisture for a very short time, some coarse sands will not hold water at all. Water holding capacity is far more important than fast drainage is for a Japanese Maple. As long as the feet are not wet all of the time and we use native soils that do not have a history of root rot causing phytophthora, like so many of the Oregon soils have, then we have little to worry about from root rotting organisms here in a warm climate. Our soil temperatures are too warm for most wet root rots to ever get established here but we can see some dry rot in some of our plants as a consequence but seldom do we ever see a dry rot on Maples but it can happen with plants grown in the ground, given too much shade and with soils that have some nutrient deficiencies, irregular watering practices and with hardened (compacted) soils that have little aeration due to them lacking adequate organic matter and thus lessening the likelihood of free flow movement of oxygen in their soil. I've mentioned before elsewhere that if we are wanting to plant several Maples in the ground then it is only prudent to learn what your soil composition is, your nutrient contents, percentage and composition of your organic matter as well as your water percolation rates, water holding capacity and your soil and water pH. Jim
Re: Did my *** Maple catch verticillium??? bis! He mentioned fertilization. Did he, and if so with what and how much.
Re: Did my *** Maple catch verticillium??? bis! thanks again for the precious advices it was a really light feritilization but it also was the first time it is always a pleasure to read your answer with high knowledge on japanese maple thanks again
