Suitability of plants can be significantly affected by management imposed related to defoliation, fertilization, and irrigation. Untimely or excessively severe defoliation by either grazing or mechanical harvest can weaken or kill plants, whereas delayed defoliation causes reduction in forage quality and yield potential. Nutrient requirements must be met for economical yield and quality and pest resistance. Irrigation systems must prevent water stress from inadequate or excessive water in the root zone.