Complex sentence: In Arizona, field observations indicated that a delay in planting until late October to November may help decrease BCTV incidence; however, changing the planting dates may not always be successful because the movements of beet leafhoppers are inconsistent and unpredictable.
Split into simpler sentences: In Arizona, field observations indicated that a delay in planting until late October to November may help decrease BCTV incidence. Through experimenting, changing the planting dates may not always be successful since the movements of beet leafhoppers are not consistent and unpredictable.