In this task, you are given a paragraph, and your task is to construct a question from the given passage. Construct question in such a way that (i) it is well explained in the paragraph, (ii) the words may/may not be present in the paragraph, (iii) it should start with what/how/describe. Avoid creating a question that (i) is just relevant to one or two sentences, and (ii) not relevant to passage. 
Q: Grass and small plants grow in an area. These plants die. The soil gains organic material. The soil becomes more fertile. Larger plants are able to be supported. Trees eventually grow. 
A: 
How do forests form?