Endless 3D plane repetition animated by script is not moving

Hey Everybody,

I am new to Unity and to C#. I am trying to move a plane via script. At the moment the plane is out of the camera view it should be deleted and a clone should pop up and so on. But nothing is really happening(depart from the fact that three clones pop up in my Hierarchy). Also I don't have any Compiler Errors. A mate of mine gave me the script written in Java(that worked perfectly) and I tried to translate it into C#. So there might be the Problem. Anyway I suppose something is wrong with this line:

 newForest = Instantiate(child, new Vector3(transform.position.x+40,0,0),Quaternion.identity) as GameObject;

And here is the full code:

 using UnityEngine;
 using System.Collections;
 
 public class ForestScript : MonoBehaviour {
 
     public Masterscript masterParent;
     
     public bool hasChild;
     
     public GameObject child;
 
     // Use this for initialization
     void Start () {
     
     }
     
     // Update is called once per frame
     void Update () {
         
         if (masterParent.bodenPlatteDown)
         {
             transform.position = new Vector3(transform.position.x, 7 * Time.deltaTime);
         }
         
         if (transform.position.x < -100)
         {
             Destroy(gameObject);
         }
         
         if (!hasChild && transform.position.x < 80)
         {
             GameObject newForest;
             
             ForestScript birthHelp;
 
             newForest = Instantiate(child, new Vector3(transform.position.x+40,0,0),Quaternion.identity) as GameObject;
 
             newForest.name = "Wald";
             
             birthHelp = newForest.GetComponent("ForestScript") as ForestScript;
             
             birthHelp.masterParent = masterParent;
             
             hasChild = true;
         }
     
     }
 }

The script should be activated by another one(Masterscript). I searched for two days now and tried to fix the problem with existing threads but nothing really namable changes. So I hope someone might have an idea. Thanks :-)