Where do branch roots originate

The branch root originates at the pericycle of the parent root, just outside the parent root's primary xylem.

Explanation:

not the best question format lol but what i think might as scale color is controlled by a single gene with two alleles, the green allele and the yellow allele. when moths that are homozygous for green scales are mated with moths that are homozygous for yellow scales, 100% of the offspring have green scales.