27<! IM.IXOIS STATE HORTICULTURAL SOCIEfV 



BOTANY AND VEGETAIU.K I'lIYSIOLOGV. 



Mr. H. H. McAfee, from the standing committee on Botany and 

 Vegetable Phjsiolog}', made the following rej^ort : 



However much we may talk of "vitality," " constitutional perfec- 

 tion," " powers of endurance," and the like, it seems to me we can never 

 reasonably expect a plant or animal to endure, unless it is in fair health, 

 when its powers of endurance are to be taxed. And if, as happens to be 

 the case with most plants in our climate, plants have to prepare them- 

 selves specially during one portion of the year, to withstand special vicis- 

 situdes and hardships of another portion of the year, it can easily be seen 

 that good health, perfect physiological development during this time of 

 preparation for hardship, is absolutely requisite, or when the hardship 

 comes suffering must ensue. 



In a climate like ours, winter po.ssesses a wide range of possibilities. 

 Compare the last with the present winter. Now we have had, except the 

 vicious snaps of October and November last, an exceptionably mild win- 

 ter. Though minus 22° has been reached in the State this winter, I ven- 

 ture to say that that minus 20° was not reached in a way that hurt trees 

 and plants as a like thermometrical index has hurt them heretofore. But 

 our winter as a whole has been mild, pleasant, and in very truth an 

 Atlantic winter, while last winter was a Steppe winter. 



I will not now stop to explain these terms, nor to enter upon the 

 subject of meteorology, which properly belongs to other hands, though 

 should time permit and you desire it, I may, before we separate, give you 

 the conclusions of some study and observations upon that subject. I think 

 that the experience and observations of horticulturists will bear me out 

 when I assert that the behavior of the subjects of our care, in the different 

 winters of about equal temperature, is often very different, showing that 

 we must look farther than to winter for a cause adequate to the effects 

 observed. A given very low temperature, may be very destructive or not 

 very destructive of certain plant life, and whether it has been destructive 

 or not depends upon some other circumstances than temperature alone, 

 else when temperature was equal, results would be equal. Finding results 

 unequal when temperature is equal, proves that it is not temperature alone 

 that kills or injures. 



There is, then, a difference in the amount of endurance shown by 

 plants at different times, and it is for us to study why plants may at one 

 time successfully resist and at another time succumb. Supposing that the 

 plant has in its nature the propensity to perfect its character in every 

 respect, to assume maximum powers of endurance, as well as to perfect its 

 life cycle of growth and fruitage, if only the surrounding circumstances 

 are favorable ; it then follows that a plant failing in point of endurance, 

 where under similar stress its powers of endurance were sufficient, must 

 have been deprived in some way or hindered from perfecting this charac- 

 ter of endurance. 



