Let's say there's a tree (we'll call it "Tree A"). We cut a branch off that tree and plant it in the ground, that branch takes root and begins to grow. At what point does that planted branch stop being "a piece from Tree A" and become Tree B? Does it EVER become "Tree B"? That newly planted branch would be genetically identical to the tree it was cut from although its' growth would be different as it was exposed to slightly different amounts of wind, rain, sunlight, nutrients, etc.
Tree B would simply be a clone of Tree A…genetically identical but a different organism pretty much the moment you disconnected it from Tree A. Just because two things are genetically identical does not make them the same organism (see Jack and Finn Harries.)
Also, a genetically identical tree wouldn’t look the same as another tree as the shape of the tree is determined by environmental, not genetic, factors (as you say.)
“In the 1890s, when Freud was in the dawn of his career, he was struck by how many of his female patients were revealing childhood [sexual] victimization to him. Freud concluded that child sexual abuse was one of the major causes of emotional disturbances in adult women and wrote a brilliant and humane paper called “The Aetiology of Hysteria.” However, rather than receiving acclaim from his colleagues for his ground-breaking insights, Freud met with scorn. He was ridiculed for believing that men of excellent reputation (most of his patients came from upstanding homes) could be perpetrators of incest.
Within a few years, Freud buckled under this heavy pressure and recanted his conclusions. In their place he proposed the “Oedipus complex,” which became the foundation of modern psychology… Freud used this construct to conclude that the episodes of abuse his clients had revealed to him had never taken place; they were simply fantasies of events the women had wished for… This construct started a hundred-year history in the mental health field of blaming victims for the abuse perpetrated on them and outright discrediting of women’s and children’s reports of mistreatment by men.”—― Lundy Bancroft