It survives by obtaining sugar through the connections between its roots and those of neighboring normal redwood(s), usually the parent tree from whose base it has sprouted.
[1] Other conifers lack the ability to graft their roots, so 'albino' mutants of other species do not survive to become sizable trees.
[7] Albino redwoods are generally regarded as parasitic plants, but as of 2016 one researcher speculates that they are supported by other trees for their role in storing toxic heavy metals.
Any species of vascular plant has the potential to inherit and express albinism, but only redwoods can produce enough nutrients (through the host/parent tree) to survive past the seedling stage.
A periclinal chimera has both mutant and normal cells distributed horizontally across the tip of each bud propagating at equal rates, leading to a very stable phenotype.