The Sectorial Chimeric Redwood exhibits the showiest color pattern of the three chimeric subsets. Mutated cells extend vertically through all cell layers within the bud or meristem, see fig below. The border between each genotype is almost always parallel within the stem giving sectorial chimeras a candy cane like appearance. Sometimes both genotypes (colors) are expressed together in individual needles giving them a beautiful split coloration pattern. Because sectorial buds have two different genotypes vertically aligned through the meristem, they tend to be unstable. In time one genotype will out compete the other causing the tree to revert either completely green or white. This is why in nature; basal sectorial chimeras rarely exceed 15’ in height.
Here's a Sectorial Chimeric branch exhibiting heterophyllous needles. Notice how the white needles appear shorter than the green. On branches that are split between both phenotypes, you can see the normal green portion of the needle curving around the white causing the tips to look bent.
Sectorial Chimeric branch reverting to the white genotype:
A Sectorial Chimera in the wild showing split green and white needles:
A sectorial branch on a greenhouse subject.
Under the microscope we can see clear lines of delineation between green and white cells on this split needle. The formation of this mosaic pattern in redwoods is a rare yet beautiful oddity.
Diagram of a Sectorial Chimera: