Agriculture is the basis for civilizations large and small. Hunters and gatherers do not develop civilizations. Plants are immeasurably important in medicine. Plants provide the air we breathe, the food we eat and they help to conserve and purify the water we drink. They are also beautiful, and beauty is always welcome.
Plants also produce wood which is still the most common fuel on the planet.
Other uses of wood are manifold. Plant fibers are used used for clothing and paper. Paper making revolutionized civilizations and helped to disseminate thoughts, art and even recipes throughout the ancient world. The flora of Hawaii contains many unique and endangered species. Their anatomy is largely undocumented.