I cannot view your photo... sorry..

depending on how large the trunk is, If you have a small truck, lets say under 4 inches.

I would pull it back, but not with wire...
an easy way is with a stake, drill a eye hoop in the top... this will hold the rope, and the rag..

wrap a rag around the trunk, tie it loosely, then tie a rope on that, and bend the tree until you can tighten to the eye hoop, tie it off..

but DO not try to bend it more then a 33% angle at a time.

within in 3 months, it should be good for another go around if needed..

But if the ice flattened it, it might never recover true.

I will paste a Link to see if you can get it. After the pic page comes up you should be able to double click on the picture and see a good view. Carol

Here is a link that might be useful: Mick's Willow Tree

oh not as bad as I thought.. was it windy when you took the photo or is the top also bending?
put a rag at the bottom branches, and one higher up (middle) if the top is bending..

never use wire, it will cut into the tree, I don't even like to use water hoses as it will rub the tree too much.

Oh and this will be a two person job.

I usually try to over bend a little bit,

I think Lowe's sells a kit, that comes with 3-4 stakes and some wrap with rope. to stake a tree.. use that to bend with.

I would also go out there and see if it has any give towards how you want to bend it..
If you had this tree staked at any time in the past... the root ball could have been pushed over.

I never stake my trees the 3-way stake.
the root ball can only get strong if left to blow in the wind on its own.

I have done this bending on a redbud and a golden rain tree.. so I know it works, and works well..

Just don't push it over too much at a time. you will know after you get a feel for the tree when you do the test

Thanks for the response.

Having pushed at the truck I'd say it will need a fair bit of pressure to get it back straight-ish but I will have a go, without doing too much at it.

Regarding the 3 way staking.....

When I asked people, some said DO because the constant rocking of the tree by the high winds which we get at times means that the roots end up loose

Some said DON'T because the tree needs to get strong on it's own.

Both suggestions seemed to make sense to me and I wasn't sure which way to go.
My Fuji apple (unstaked) has managed fine, so did the little pear tree I put in 2 years ago, until a large branch fell on it from another tree during the ice storm and smashed off half the branches. (it's still hanging on in there though)

Maybe I chose the wrong way :-(

Mick

That almost appears to be leaning due to prevailing winds.

I would use a couple of stakes on the side away from the lean and gradually train it back to a semi-straight attitude. A little bit of downwind side pruning might help out a bit as well.