When should pampas start growing in NE Arkansas? No sign of any green growth yet and it's the end of May ?
Have you cut this down already for the new growth to come up? You should wait to trim these until they start to grow green here and there. Pruning them early in the fall instead of spring can cause the plant to die prematurely due to cold weather, and the crown being exposed to it. This article will help on the care of this grass: https://www.gardeningknowhow.com/ornamental/foliage/pampas-grass/growing-pampas-grass.htm