Number was plucked out of my ass. But sure, let’s look at a redwood and see when they start reproducing.
The Sierra Redwood can reproduce sexually (seeds in cones) as early as 24 years old, but one source I found said that seeds are usually not high-quality until the tree is 200+ years old. It also takes about a 2-year maturation period within the cone before being ready for planting. Other types of redwoods can reproduce asexually, which may have an effect on the rate of expression of the mutated genes.