This is my 2nd season with Japanese maples and I just spent the whole day yesterday planting a 20 gallon Hogyoku. I had noticed some dieback on a few branches before but after my excitement of purchasing and planting it, noticed that the there was quite a bit dieback and some of them on the branches off the main trunk. Then I noticed the black scars/spots on the main trunk and the bigger trunks which I previously had mistook for scars off aging on an older tree. I in zone 8a where it gets quite hot in the summer and we also have clay soil. I've amended the soil with pine bark mulch, PermaTill and planted the maple under couple of huge tree that provide filtered light/shade after about 2-3 pm. If this is Verticillium Wilt, can this tree be saved under these conditions? I spent quite a bit of money on this and don't want it to go to waste. Also, I have about 5 other Japanese maples and a new Acer Rebrum close by in the back yard and another 5 in the front yard. I am worried that this might affect the other maples through things like contaminated leaves and even aphids. Thanks in advance for your help and expertise.
Good afternoon @fatlever and welcome to tbe maples forum. First, maples will have natural die back inside of the canopy from lack of light. This can be reduced by thining the tree in Summer and at the end of Winter into very early Spring. Next thing to do is remove all the obvious dead branches, this can be done at any time of the year. Looking at the trunk, it appears to me to be natural ageing, so nothing to worry about. I cannot see any of the black spots you mention. If you want to check for Verticulum, then cut a branch and look at the cross section. If there are black rings then VW is present. Large strong specimens can live with VW for many years as long as they don't get too stressed. Re care, then watering regularly in hot Summer's is essential to avoid unnecessary stress, and especially for a newly planted tree. The first 2 years it is important to be on top of watering. Obviously potted maples need a regular watering regime whatever the age.
Oh wow, thank you Acerholic. I wasn't expecting such a quick reply from one of the forum's experts. Makes me feel relieved a bit and not continuously checking the tree. I'll follow your advice and remove the dead branches and cut a branch to see if there are any signs. I learned my lesson last summer about regular watering when it gets hot here so plan to keep up with that this year. Acquiring and growing these maples has turned into a big addiction in under a year and this place has provided invaluable information.
I also see no signs of V. wilt. I wonder if you haven't planted a little too deep, I can't see the root crown. You probably want to check that the top roots are coming out of the trunk right at the soil level, as nurseries very often plant too deep. The wilty looking leaves are just normal spring leaves, AFAICT. We have a Hōgyoku that has lived with Verticillium for maybe 20 years, and is quite large, if a little lopsided! It now only loses a branch very occasionally, though some great stress may finally bring the infection back to the fore. It's a tree many visitors admire in autumn, with the rather late pumpkin orange colors. Good luck!
While I agree with the assessment of planting depth, I also noticed that the maple is planted in a raised berm/mound which will go some way to mitigate any potential problems. I think due to rain and gravity the tendancy will be for the soil to erode away from the area around the trunk without any intervention. Also agree that marks on bark are natural and no obvious signs of ill health.
I actually excavated around the trunk to expose the roots but some of the mulch tends to flow and cover the trunk area when I water. When it dries out a bit, I clear the area again. If I try to completely strip away around the ball to the level where the root flare is exposed, I find myself tearing out a ton of roots since the root flare was buried ~30% deep into container I got. So in instances like this I tend to have a crater around the root ball, mounding up going out and sloping down after that -- with flare a few inches above ground level and the with the root ball placed on a small rock. Thanks everybody for the feedback that there is no verticillium wilt. In just a few days, the maple is looking so much better than when I first got it from the nursery.
