Albino redwood
An albino redwood is a redwood tree which is partially or totally unable to produce chlorophyll, and therefore has some to only white needles instead of the normal green.
Description and biology
Albino redwoods survive by obtaining sugar through the connections between its roots and those of neighboring normal redwood, usually the parent tree from whose base it has sprouted. Sap exchange through roots is a general phenomenon among redwoods. About 400 are known. They can be found in Henry Cowell Redwoods State Park, Humboldt Redwoods State Park, San Francisco Botanical Garden, Huddart Park, and The Santa Lucia Preserve, with eleven trees in the first. The exact locations are not publicized to protect the rare trees. They reach a maximum height of about. Other conifers lack the ability to graft their roots, so 'albino' mutants of other species do not survive to become sizable trees.Six phenotypes of albino redwood have been classified: white, bright yellow, cellular virescent green, pale green, mottled and nonchimeric variegated. Such mutants can be either basal or aerial. The bright yellow form is exclusively aerial and is thought to be associated with excess xanthophyll production. The pale green form lacks just one specific type of chlorophyll and is almost always basal. Cellular virescent green trees have a few normal cells interspersed among the mutant cells.
Ten cases are known of chimeric redwoods that have a mosaic of albino and normal tissues. Only a single chimeric redwood is known to produce cones. Formerly threatened by the Sonoma–Marin Area Rail Transit rail development, it has since been replanted.
Three phenotypes of chimeric redwoods have been noted: sectorial, mericlinal and periclinal. In sectorial mutants, albino cells are present vertically through all cell layers, with genotype boundaries usually parallel to the stem. Mericlinal trees have mutant cells in only some cell layers and have an unstable phenotype; the albino cells can disappear and reappear in successive years. 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.