One deciding factor of the length of a plants life is the roots ability to resist disease. This factor is the reason that conifers have been around for so long. Their root systems are not only disease resistant, but also very hardy. This reason, along with others, is why conifers are so valuable to humans. They make up most of the trees in the forest, and are used as the primary source of lumber and paper products.
Conifers are on a long list of plants classified as dicots.
A notable characteristic of dicots is that their stems develop concentric rings through which dissolved nutrients that were gathered from the roots are distributed to the leaves and other parts of the plant. Around the vascular tissue in their roots are layers of cells. Outward cell division on the epidermis forms a thimble-like mass of unorganized cells called the root cap. On the root cap are root hairs. These root hairs are tiny extensions off of the tip of the root.