Maya has a variety of deformers that can be useful for modelling or animating. Above I'm starting out with a basic tree. I then drew a line that followed the tree trunk so now when I change the line, the tree will follow along.
On the left, I have a modification tool where I click a point on the tree and colors will appear indicating the area of effect (yellow changes more compared to red and then none further away). So I can use that to move, rotate or scale different parts of the tree. In the middle, there's the basic bend deformer. On the right, I can deform the tree by manipulating the cone represented by the two circles.
Here on the left is the squash deformer that I also used on the tires of the scooter. What's nice is that it isn't just making the tree shorter but fatter in the center too. Next is a twisting deformer and then a wave deformer. Below is showing how you can apply multiple deformers and that the order you apply them matters. On the left you have a cylinder followed by a bend deformer and then a wave deformer is applied on top of that. On the far right, you can see the result if a wave deformer is used prior to the bend.