In Andropogoneae, what type of glumes are present?

In the Andropogoneae tribe, the glumes are characterized as long and indurate. This means they are typically hard, which provides structural integrity and protection to the developing seeds and florets within the inflorescence. The rigidity of the glumes helps prevent damage from external factors and aids in the dispersal of seeds. This feature is crucial for the survival of the plants in various wildland environments, where seeds are often subjected to physical stresses.

In contrast, the other options describe glumes that do not align with the typical characteristics of Andropogoneae. Soft and flexible glumes, for instance, might be found in other grass groups that require different adaptations. Short and membranous glumes might provide a different kind of structure insufficient for the specific ecological niches Andropogoneae occupies. Similarly, thin and fragile glumes would not provide the necessary protection against environmental challenges faced by these grasses. Thus, the distinguishing feature of long and indurate glumes is key in identifying members of the Andropogoneae tribe.