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Hi Ash,

I'm still in two minds as whether to air layer or carve/thicken the trunk in the appropriate areas. Ideally, I would like to avoid a chop and have a tall, powerful trunk, but I will see how it goes.

I had a good look today in the daylight at the soil. I found 4 more rotten woody roots of about 4-5mm that pulled straight out of the soil. I was a bit concerned by this, as they were located at various points around the tree and so decided to pop it out of its pot to take a look at the root mass and the extent to which rot has set in.

There were a lot of healthy white feeder roots around the root ball, but as I could immediately see more thick rotten roots, directly underneath the centre. I gently took a root fork and agitated the soil, which thankfully just fell away with little or no effort by tapping it. This revealed yet more dead roots, some over 1cm thick, all decaying further and further up the root system, all caked with thick wet clay and compacted, unscreened soil, which was exacerbating the problem.

Although the tree looks healthy enough at the moment, It would be 5 months or so before I would perform the planned repot. I didn't want to leave the roots there in wet clay to carry on rotting over winter, as it would easily have started to eat the bottom of the trunk away and spread to other parts of the root mass. By then I could be in real trouble. I decided on the strength of what I saw to do an emergency repot.

As the soil around the feeder roots had fall away with great ease, they escaped virtually untouched. I placed the tree in a bucket of tepid water for 10 minutes to allow the surface clay to get mushy, then using a root hook, I gently worked it out of the nebari and base of the tree. A couple of squirts with the hose and it was all gone. With all soil and clay removed, I could easily see the rotten material and cut it away back to healthy parts.

I reused the same pot, placing a layer of fired clay pellets at the bottom, then screened compost - like my other two elms live happily in. As none of the feeder roots were pruned, and only dead material was removed, the impact on the tree has been kept to an absolute minimum. The new soil drains very well, and retains moisture, but allows for a good mix of air too. We've got about 6 weeks before Autumn really arrives here in S.E. England, and roots will still continue to grow all the while the temperature is above 10c/50f.

Although Chinese elms are tough as old boots, I'll be paying particular care to this tree come the Winter, as the roots have been disturbed this late in the year. Repotting a deciduous tree in Autumn is not something I would recommend in general, only under certain circumstances as the lesser of two evils. However, normal repotting is mostly accompanied by a root prune too, something that hasn't been performed here.

Any effects of this repot should be visible within the next week to 10 days. I'm confident that the tree will sale through without any problems.

All the best,

Aaron

16-Sep-2005	#4
Aaron_K bonsaiTALK Master Chief Join Date: Mar-2004 Country: England USDA Zone: 8 AHS Heat Zone: 2-3 Posts: 1,477	Hi Ash, I'm still in two minds as whether to air layer or carve/thicken the trunk in the appropriate areas. Ideally, I would like to avoid a chop and have a tall, powerful trunk, but I will see how it goes. I had a good look today in the daylight at the soil. I found 4 more rotten woody roots of about 4-5mm that pulled straight out of the soil. I was a bit concerned by this, as they were located at various points around the tree and so decided to pop it out of its pot to take a look at the root mass and the extent to which rot has set in. There were a lot of healthy white feeder roots around the root ball, but as I could immediately see more thick rotten roots, directly underneath the centre. I gently took a root fork and agitated the soil, which thankfully just fell away with little or no effort by tapping it. This revealed yet more dead roots, some over 1cm thick, all decaying further and further up the root system, all caked with thick wet clay and compacted, unscreened soil, which was exacerbating the problem. Although the tree looks healthy enough at the moment, It would be 5 months or so before I would perform the planned repot. I didn't want to leave the roots there in wet clay to carry on rotting over winter, as it would easily have started to eat the bottom of the trunk away and spread to other parts of the root mass. By then I could be in real trouble. I decided on the strength of what I saw to do an emergency repot. As the soil around the feeder roots had fall away with great ease, they escaped virtually untouched. I placed the tree in a bucket of tepid water for 10 minutes to allow the surface clay to get mushy, then using a root hook, I gently worked it out of the nebari and base of the tree. A couple of squirts with the hose and it was all gone. With all soil and clay removed, I could easily see the rotten material and cut it away back to healthy parts. I reused the same pot, placing a layer of fired clay pellets at the bottom, then screened compost - like my other two elms live happily in. As none of the feeder roots were pruned, and only dead material was removed, the impact on the tree has been kept to an absolute minimum. The new soil drains very well, and retains moisture, but allows for a good mix of air too. We've got about 6 weeks before Autumn really arrives here in S.E. England, and roots will still continue to grow all the while the temperature is above 10c/50f. Although Chinese elms are tough as old boots, I'll be paying particular care to this tree come the Winter, as the roots have been disturbed this late in the year. Repotting a deciduous tree in Autumn is not something I would recommend in general, only under certain circumstances as the lesser of two evils. However, normal repotting is mostly accompanied by a root prune too, something that hasn't been performed here. Any effects of this repot should be visible within the next week to 10 days. I'm confident that the tree will sale through without any problems. All the best, Aaron __________________ Do not follow where the path may lead. Go instead where there is no path and leave a trail. - Muriel Strode Vulpes pilum mutat, non mores! "A fox may change its skin but never its character"