Turning off iskinematic

Hi im looking for a way to turn off iskinematic when my trees health is below 0 here is what i have currently

#pragma strict


var chop = 1000;


function ApplyDamage (Damage : int)
{
	chop -= Damage;
	if (chop <= 0) 
	{
		Dead();
		
	}
}

function Dead()
{
	Destroy(gameObject);
}

im looking for it to instead of destroying the game object straight off the bat i want it to disable iskinematic to it falls through the floor and then destroys game object after a set time any idea how i can do this

This

Destroy takes a time parameter

fixed it here is the script for anyone needing it

#pragma strict

rigidbody.isKinematic = true;
var chop = 1000;
//var isKinematic: bool;

function ApplyDamage (Damage : int)
{
	chop -= Damage;
	if (chop <= 0) 
	{
		Dead();
		
	}
}

function Dead()
{
	rigidbody.isKinematic = false;
	Destroy (gameObject, 5);
}