A five year old Acer that is poorly

In 2008 we planted a small acer in a semi-shady corner at the back of the garden and fed it with ericaceous compost, as required for our clay soil. By 2010 it was blooming well and I attach a picture. This year it is poorly. Although there are some leaves, most of the buds are withering on the branches. I attach a photo taken today plus a close-up. I know it's not October (like the "thriving" picture date) but even so, I'm worried! I have re-fed it a bag of ericaceous compost, in case it was nutrient-lack. Perhaps it's down to the unusual weather (excess rain and cold) that we've had. But is the tree dying? What can I do to make it live? Thanks in advance for any tips.

 

I have had two of these trees die on me this year for no apparent reason. Having said that, we must remember we had snow and freezing conditions in April after the poor things were starting to waken up, and very considerable quantities of rain (they like moist soil but not soaking wet all the time :()
A fifteen year old Senkaki has just succumbed (similar to Sango Kaku) but that is a particular variety that is liable to just 'up and die' seemingly without reason. With mine the leaves had been getting progressively smaller over the past two years, and it went into autumn colour very early last year, so the warning signs were there
Sad to say, I think your little tree is having some difficulties and I have no bright ideas for an instant cure :(

 

T hey need ericaceous soil??? I just bought and planted one in my clay soil because the chap at the shop said it would be fine!

 

Don't despair Lea ... I remember a chap from Poland who grew super Japanese maples and did so in clay soil. They DO prefer a slightly acid free draining soil with a constant moisture content, but NOT wet, out of the wind and sheltered from a strong sun (they are somewhat 'hard to please' little bu**ers ) They do however grow quite happily in anything except a strong alkaline soil

 

We have incredibly alkaline heavy clay soil Lea, and my five year old acer, grown from a cutting given to us by my BIL, is going great guns (even after being split down the middle after heavy snow in February - I bandaged it as advised on here and it's looking amazing). I've never fed it, except with the occasional layer of home made compost, and it's survived winds of over 100 km/h, numerous heavy snow falls, and this year we've had the coldest and wettest spring on record.
Here's a photo of it taken last autumn:

 

Oh, and it's in full sun, so very often gets subjected to very hot, dry summers with temps in the high 30sºC

 

That is incredible for two reasons ... ONE ... they are not fussy on alkaline soils, but ...TWO... they are almost impossible to grow from a cutting
AND ... all of your other conditions are very anti Japanese maples
It looks fabulous .... we must apparently move to Spain

 

I know Sam! I am very surprised at how happy it seems! It is definitely my favourite tree, so I thought I'd lost it when I found the main trunk split down the middle and half of it on the ground a few months ago, but at the moment it's full of leaves and looking very healthy! Don't you just love it when plants break all the rules?!

 

I have clay soil, which is on the acidic side