We investigate the relation between degree sequences of trees and the majorization order using the Muirhead theorem. In this way, we prove a theorem that provides a necessary and sufficient condition for delta sequences of trees to be comparable in the majorization order. Although our investigation is largely theoretical, our study contributes to a better knowledge of trees as an important data structure. We point out that this study is among the few combining Lorenz curves and majorization on the one hand, and degree sequences of networks on the other.