The influence of Roethke on Plath's poetry is no secret, however in an essay by Roger Elkin, 'Hidden Influences in the Poetry of Ted Hughes and Sylvia Plath', Elkin explores the idea that Roethke's poetry and creative theories greatly influenced Hughes also.
It's a fascinating essay detailing not only the similar themes and techniques such as animism and minimism and use of Jungian symbolism in the poetry of all three but also the role/purpose of poetry to tap into and explore the primitive, pre-conscious thus universal self. He obviously analyses Plath's 'Poem for a Birthday' but also thoroughly analyses Hughes' 'Wodwo' in the light of Roethke. You can find the essay here.

The releasing of the previously unpublished poem 'Last Letter' by Ted Hughes has caused a fair bit of interest in the news over the last week. Anything that can shed light on those final days before Plath's death is of great interest to Plath fans though it may seem a little voyeuristic to some. Anyhow I thought I'd give some of my thoughts on the poem as a biographical document rather than as a poem.

The main surprise is that on the Friday before her death, Plath had posted a letter of goodbye to Hughes which he had received earlier than she'd expected -

"Your note reached me too soon—-that same day,
Friday afternoon, posted in the morning"

..."That was one more straw of ill-luck
Drawn against you by the Post-Office"

So she posted the letter in the morning possibly assuming he would receive it the following day. Instead he got it that afternoon and rushed around to her flat fearing the worst. She was getting ready to spend the weekend with friends. The insinuation is that her plan was to let him stew in panic over the weekend not knowing  whether she was dead or alive and if alive no idea where she was -

..."Had I bungled your plan?
Had it surprised me sooner than you purposed?
Had I rushed it back to you too promptly?
One hour later—-you would have been gone
Where I could not have traced you."

"How I would have got through that weekend.
I cannot imagine. Had you plotted it all?"

Yet Hughes arrives at her flat, Plath burns the letter and Hughes is seemingly reassured enough after seeing her to leave her alone with their children and go off for the weekend with no further contact with her.

"My last sight of you alive.
Burning your letter to me, in the ashtray,
With that strange smile."

..."But what did you say
Over the smoking shards of that letter
So carefully annihilated, so calmly,
That let me release you, and leave you"

The poem tells us that he spent the Sunday night with Susan, who turns out to be Susan Alliston, a poet who died in 1969 of Hodgkin's disease. Hughes wrote the introduction to her book of poems. Another surprise - Assia wasn't the only other woman he was having an affair with. The strangest part is that they spent the night in the same room / flat on Rugby street where Hughes and Plath had spent their wedding night, the very bed even -

"Susan and I spent that night
In our wedding bed. I had not seen it
Since we lay there on our wedding day."

There is also the suggestion that Plath phoned Hughes several times during that last Sunday night and early dawn on Monday. Hughes being the only one privy to her last diary entries, she may have recorded such fruitless attempts to get in touch with him -

..."How often
Did the phone ring there in my empty room,
You hearing the ring in your receiver"

"Towards the phone booth that can never be reached.
Before midnight. After midnight. Again.
Again. Again. And, near dawn, again."

The poem is another bizarre addition to the mystery of events. Clearly, to my mind, Hughes wanted this poem published posthumously otherwise he would have destroyed it instead he entrusted a typed copy of it to his wife, Carol.

I've got to say, I like our present poet laureate but her response to the poem as "a bit like looking into the sun as it's dying" is surely the most hyperbolic twee I've ever read!

Very exciting news for Plath and Hughes fans - the British Library has recently published a cd of all Plath's recordings including interviews with Plath and Hughes not publicly available since the original broadcasts, a live recording of Plath reading 'Tulips', Plath describing her experiences of being an American woman in England as well as Plath and Hughes talking about how they met.

The Spoken Word CD is 73 minutes long and includes a booklet containing an introduction by the Plath scholar Peter Steinberg of the excellent Sylvia Plath info blog where you can read a review of the cd here. The cd can be purchased here.

A nearly eight minute podcast taster from the cd can be heard here.