A reasonable question to ask oneself about this time is: "When should the experiment be terminated?"  One objective criterion for ending the study has to do with parent leaf death.  As long as a parent leaf is alive, it may be contributing to the growth of the new vine or roots.  At the very least, it could be assumed that it may contain certain valuable nutrients that, as it approaches death, might be transferred to its progeny as an inheritance, so to speak.  This being the case, it would seem only reasonable to wait until all original parent leaves in all tanks had died before ending the study, as all new plant tissues would then have had an equal chance to get everything possible out of the parent leaves that produced them.

Operating on this basis, it would appear that we may be close to wrapping up our first experiment.  All seven parent leaves are long gone in Tank 2, six are dead in Tank 1, and just over five have died, on average, in Tanks 3-6.  Consequently, we shall attempt to preserve until the last few parent leaves expire, which should not be too much longer.