I think you have two options... take it down or paint it white.... the tree needs to go though it's not helping at all.

I'm not sure you can't hire a mason to come in and mortar all around making it flat?

painted lava on a budget.... it's the best option.

Do you actually use the fireplace?

I'd remove all the lava rock. Painting would make it look a little better but making it completely go away from your sight and your brain would be the way to go.

Lots of options for re-doing the fireplace. Make it smaller. No reason why it needs to span the whole wall. Plus it will cost less.

If you do that then the tree dilemma is solved because there's no room for it. Esp. true if you add a mantel.

I (unfortunately) remember when these were all the rage. Just paint it (vac and scrub well first).

First choice: remove and replace with stone or tile that you like.

Second choice: stucco the whole thing and get that in the color you like. I'm not convinced the rocks will look meaningfully better when painted.

We do use the fireplace. I feel the same way about painting. I've looked at lots of pics of painted stone and while it looks better in some cases I don't care for it. I like the look of stone, just not 70's lava rock stone! I like the 1st pic but it's really small. What kind of stone is that? I think something like that would suit our house.

I agree with acm. If you can't remove it, you need to do something stronger than paint (i.e. stucco) to cover that kind of rock - I remember lots of pores and pits in the volcanic rock around our house.

Depending on the type of fireplace, you may also be able to drywall over most of it too. I think wood fireplaces are too hot for that, but some gas models may work (double check that first, of course).

I would recommend turning into more of a room feature piece. What is your style and how do you want the room to feel? The tree is really neat and might pop beautifully against a white version of the fireplace, or a different style fireplace. White is very modern looking and will definitely make the room feel fresh.

You might be able to find affordable ways to remove/re-design it,. Assuming budget is a concern, I am thinking of those brick slabs you can buy at the hardware store, do you know what I am talking about? If the purse strings are extra tight at the moment then paint is always a great option (as discussed above) and can be as temporary or permanent as you choose. At least it would give the space a face lift while you decide on a permanent solution.

Judging from the baseboards, the whole room needs a bit of an update so really think about your style, how you use the room, etc. and save a bunch of ideas, it is easier to translate an idea into reality with visuals.

demo it and the tree needs to disappear too

I'm not sure getting rid of the tree is a given. We can't really see it enough in that picture in my opinion. I'd agree that the rock doesn't show it off though.

I wish I had a better photo but this was all I can find in my phone. I mixed some white paint with water and whitewashed ours. Looks so much brighter and cost me nothing. Win, win if you ask me.

If the rock stays the tree must go because no one can see it. If the rock stays paint it. Black, white or something in between. The rock wall is kind of the 'art' for the room. Let it stand without too much distraction.

I prefer the wall with nothing around it, but if you need something consider perhaps a contrasting metal wall sculpture.