These white bugs i thought where springtails and i read were "harmless" however you can see from the leaves that this clearly is not the case as the leaves are drying out.
Are they mealy bugs?
Anyway my course of action i want to double check is to slip pot and treat with a neem oil drench.
it does need a re pot and the soil is too organic and holding onto to too much moisture. - but given the time of year and its distress i will only slip pot.
Its still pretty mild here in the uk about 19 degrees in the day 11 at night.
I do have lime sulphur for a more nuclear option but am worried on causeing more damage.
Any input would be grately recieved.
Thank you

 

I can't tell what plant you have, the leaves should not be brown, lack of water probably. As for what the white bits are no idea. Neem oil works but not instantly, you will not see a result for a couple of weeks. Lime sulphur will not do anything so don't, and don't repot. The tree is stressed enough.
Do you know what species it is/was?  I assume from what you say that it is outside, put it in some shade not a lot of sun and keep it watered. Wait and see what happens.

thank you.
European beech.
Definately not a lack of water, the soil is very organic and i think tholds too much water.
Yes it is outside.
just trying to identify what the infestation is 
 

Well, definitely not too much water unless it has been sat in water, we have had no rain for four months. Lime sulphur is a winter wash and not when leaves are on the tree.
The leaves should still be green which is why I think it has been dry at some point. I would get a brush, toothbrush will do and brush whatever the white bits are off the root base. It does not look like whitefly as they would be on the leaves not the soil, then wait and see. 
Geoff.

is that the only tree you have?

no, i have an english oak and copper beech next to it, a hand ful of acers and an ash.
All fine 

thanks Geoff,
the white bugs in the soil were crawling all over the branches the other day and?i gave thm a good dose of S&B* and that seems to have cleared up the leaves put the soil is still crawling.

The image attached is from the other day

*https://www.kaizenbonsai.com/products/bonsai-invigorator-bug-killer-and-fungicide

They look like Whitefly, unusual that they are on the soil unless what you have sprayed with has hit them. Are there any under the leaves? I still don't think they will have caused the leaves to die like that,

the leaves are clean now.
Soil still crawling.
I think im going to scrape away the surface soil gently and treat with neem.
Then Remove from its pot as the soil is too organic and not drying between waterings and sit it on some fresh well draining mix and cover  the scapred away top soil.
im hoping that will see it though the winter, its obviously going to drop all the leaves early.
Depending how vigouros the bud growth/swelling in spring (if any at all ) i might re pot, but probably leave it over potted for a year to ready for a re pot in 2027.

Beech should not drop leaves, they normally hold until new buds are starting to swell. Sounds a good idea, you can also if you think it is not draining make holes in the surface, a screwdriver or similar will work. I have also used another method that is to cut wedges out of the soil and refilling with fresh soil with a small pot maybe three around the pot. Works a treat.