Once the male flowers have reproduced and released their pollen the plant will die back.
(the male flowers; have reproduced; ) (the male flowers; released; their pollen) (the plant; will die; back; T:Once the male flowers have reproduced and released their pollen)
the male flowers the male flowers the plant
have reproduced released will die
their pollen
back T:Once the male flowers have reproduced and released their pollen