By Coadhall
United Kingdom 
I have an Acer palmatum which we have had for over 10 years. it was originally in a pot until we moved to a house with a garden an planted it in what is quite heavy clay soil and it started dying with the branches going white. I have now replanted into a larged pot with good standard compost and it seems to be doing well, but have noticed today that the main branch is turning white again and seems to be dying. any one got ideas
Thanks for the responses so far, have attached a couple of photos of the main branch and some of the side shoots. thank you
1 Jan, 2013
Answers
Also if it is alive make sure you have potted it in ericacious compost.
1 Jan, 2013
I'd very much like to see a photo of the whitened stem - do you mean the stem is actually turning white itself, or that its covered in a white deposit?
2 Jan, 2013
When I first read this I wondered if it was lichen. or a pale bark that got paler as the wood ripened?
I think a photo would be a brillant idea too Bamboo.
4 Jan, 2013
It could be drainage but the number one thing to get right with Acers is shelter. They really hate being in the wind and die back/leaves turn crispy. If I where you I would check that it is alive by scraping a bit of bark away with your fingernail. Green is good. Check if the pot is not too wet and has good drainage and make sure if it is in a sheltered position.
1 Jan, 2013