the lighting doesn't make any sense on any of them. the foliage and the trunks are shaded according to entirely different light sources, you need to give more thought to this and decide where shadows will be cast and how light will behave (making sure, of course, to use a single, consistent light source). The first suffers from the fact that the separate shapes that compse the trunk are too distinct: you must balance the volumes of the trunk as a whole with the distinction between the smaller components. Don't lose sight of the big picture.
I updated it. I want to know which one is the best. So please answer.
I like it. In the places on the trunk where the darkest pixels are in contact with the clearest pixels, it would look better to antialias.
Thank you for the comment Ska! ^__^ I'll make sure not to make any more useless comments on my own work in the future. I'll also try and use some cool references of trees next time.
You see the area above? That is where you comment on your piece; NOT in your own comment section. I have placed your comment in your description and replaced your images with links.
In the future do not post comments on your own piece unless you are replying to someone else.
In some cases it is alright to place an image in a comment here or there, to illustrate a point (ie making an edit for someone else). But do not post half your gallery in a comment on your own piece!
two lightsources is a bit advanced for you at this point. learn to do one well first. the foliage is not affected by this "right" light source, and the trunk is not affected by the "up" light source. And your foliage seems unable to cast a shadow itself.