A sapling is a young tree that's been growing for several years and begun to establish itself as a part of its community. It's demonstrated an ability to acquire the light and water it needs, and it has high potential to become like the more mature trees around it. To continue to grow and develop, however, a sapling must constantly acquire more resources. A successful sapling invests its energy in extending its root system.
A tree employing a "go deep" growth strategy extends roots as far as possible into the ground and has the additional benefit of increasing its resistance to storm winds and drought. It's best if this strategy is balanced by increased growth above the ground, which increases the plant's productivity (that is, the ability to convert energy, air, and water to a substantial, tangible material).
If a graduate student is a sapling, graduate school is a tree nursery. The trees are arranged in cohorts (often transplanted), and the nursery staff lends a hand by mowing the grass, looking after the trees' welfare, and helping them acclimate. Despite the external assistance that's available, each tree must actively take up resources and rely on internal processes for growth.
A sapling can survive by maintaining its initial state—acquiring enough to live another day. The very word "survive" seems to indicate a struggle for life. In contrast, a sapling exhibiting a healthy state, able to acquire necessary resources and turn raw materials into productivity, is said to thrive.
You'll occasionally have people talk about "Surviving Graduate School," but that doesn't reflect the possibilities and opportunities for growth. It's possible for a graduate student to "survive" graduate school (earn a degree) by (1) working with an advisory committee, (2) meeting the minimum degree requirements, and (3) completing coursework satisfactorily. But as a tree, such a student would have very shallow, under-developed roots.
In contrast, the "root system" of a thriving graduate student would be deep and vitally connected to important resources on campus, in his academic field, and to members of the community. Such a student's "branches" would be healthy, upright, growing in many directions (in balance), and working to produce "fruit." It's possible to grow and develop in graduate school—to increase one's ability to learn, think, understand, and express oneself. And it's reasonable to expect to produce something of value in graduate school. If we can help you, contact us.