Instantiating Prefab

So, im following this post: http://answers.unity3d.com/questions/685405/mass-place-trees-tagging.html.

And all working good. But i want to chance something, and i need some help. Im very newbie on this.

 #pragma strict
  
  public var player : Transform;
   
  private var paryTrees : TreeInstance[];
  private var pvecTerrainPosition : Vector3;
  private var pvecTerrainSize : Vector3;
  private var pgobTreeCollide : GameObject;
  private var pvecCollideScale : Vector3;
  private var pbooCollideWithTrees : boolean = false;
   
  function Start()
  {
      // Get the terrain's position
      pvecTerrainPosition = Terrain.activeTerrain.transform.position;
       
      // Get the terrain's size from the terrain data
      pvecTerrainSize = Terrain.activeTerrain.terrainData.size;
      // Get the tree instances
      paryTrees = Terrain.activeTerrain.terrainData.treeInstances;
       
      // Get the invisible capsule having the capsule collider that makes the nearest tree solid
      pgobTreeCollide = GameObject.Find("Tree"); // This is a capsule having a capsule collider, but when the flier hits it we want it to be reported that the flier hit a tree.
       
      // Are there trees and a tree collider?
      if ((pgobTreeCollide != null) && (paryTrees.length > 0))
      {
          // Set a flag to make this script useful
          pbooCollideWithTrees = true;
          // Get the original local scale of the capsule. This is manually matched to the scale of the prototype of the tree.
          pvecCollideScale = pgobTreeCollide.transform.localScale;
      }
      // No need to use this script
      else 
      {
          Debug.LogWarning( "NO CAPSULE NAMED TREE FOUND, OR NO TERRAIN TREES, DESTROYING SCRIPT..." );
          Destroy(this);
      }
      
      // has the player been assigned in the Inspector?
      if ( !player ) 
      {
          Debug.LogWarning( "NO PLAYER OBJECT IN THE INSPECTOR, DESTROYING SCRIPT..." );
          Destroy(this);
      }
  }
   
  function Update() 
  {
      var L : int;
      var triTree : TreeInstance;
      
      //var vecFlier : Vector3 = sctFly.svecXYZ; // My protagonist's position, passed by a static variable in a script called sctFly.
      var vecFlier : Vector3 = player.position; // using the player transform, dropped in the inspector
      
      var fltProximity : float;
      var fltNearest : float = 9999.9999; // Farther, to start, than is possible in my game.
      var vec3 : Vector3;
      var vecTree : Vector3;
      var intNearestPntr : int;
       
      // Test the flag
      if (pbooCollideWithTrees == true)
      {
          // Find the nearest tree to the flier
          for (L = 0; L < paryTrees.length; L++)
          {
              // Get the tree instance
              triTree = paryTrees[L];
              // Get the normalized tree position
              vecTree = triTree.position;
              // Get the world coordinates of the tree position
              vec3 = (Vector3.Scale(pvecTerrainSize, vecTree) + pvecTerrainPosition);
              // Calculate the proximity
              fltProximity = Vector3.Distance(vecFlier, vec3);
              // Nearest so far?
              if (fltProximity < fltNearest)
              {
                  // Remember the nearest
                  fltNearest = fltProximity;
                  // Remember the index
                  intNearestPntr = L;
              }
          }
          // Get the closest tree
          triTree = paryTrees[intNearestPntr];
          // Get the normalized tree position of the closest tree
          vecTree = triTree.position;
          // Get the world coordinates of the tree position
          vec3 = (Vector3.Scale(pvecTerrainSize, vecTree) + pvecTerrainPosition);
          // Scale the capsule having the capsule collider that represents a solid tree
          pgobTreeCollide.transform.localScale = (pvecCollideScale * triTree.heightScale);
          // Add some height to position the capsule correctly on the tree
          vec3.y += pgobTreeCollide.transform.localScale.y;
          // Position the capsule having the capsule collider at the nearest tree
          pgobTreeCollide.transform.position = vec3;
      }
  }

on the object "Tree" im using this:

 #pragma strict
 
 var Collected : boolean = false;
 
 private var showGui : boolean = false;
 
 var recurso : Transform;
 var player : Transform;
 
 function Update()
 {
 
     if(Collected == true)
     {
         MakeRecurso();
     }
 }
 
 function MakeRecurso()
 {
     Instantiate (recurso, player.transform.position, Quaternion.identity);
     Collected = false;
     showGui = false;
 }

and this:

 #pragma strict
 
 var Health = 100;
 
 function Update ()
 {
     if(Health <= 0)
     {
         
         Dead();
         
     } 
 }
 
 function ApplyDammage (TheDammage : int)
     {
         Health -= TheDammage;
         var ManageScript : ManageWood = GameObject.FindWithTag("Tree").GetComponent(ManageWood);            
         ManageScript.Collected = true;
     
     }
 
     function Dead()
     {
     
         Destroy(gameObject);
     
     
     }
 
 

Everything works great, no problems. When I approach a tree the object move to that tree and I hit the object and it will drop logs. Perfect!

But as you can see this object has a life stats. And it disappears when it is destroyed.

I need to modify my script so that this object is instantiated from a Prefab. When the script detects that the object is destroyed it will instantiate a new one.

Can anyone ELI5 me please?