The evening session was called to order at 8:40 P.M. by President Smith. The total attendance of the evening was approximately one hundred.
The evening was devoted to two stereopticon lectures, the first being slides by Professor Fagan, illustrating the lecture of the afternoon on the "Nut Survey of Pennsylvania."
This was followed by an illustrated lecture by Dr. J. Russell Smith, President of the Association.
NEW TREE CROPS AND A NEW AGRICULTURE
Presidential Address
Dr. J. Russell Smith, University of Pennsylvania
We have all heard of the scientist who made a discovery and exclaimed, "Thank God! This can't be of any possible use to anybody!" This useless aspect of science in a world with so many possibilities of service does not appeal to me. I hope that science and service and utility may go hand in hand.
The conservation of natural resources, the creation of new ones is a topic which combines the qualities of science, service and utility.
Of all our resources the soil is the most vital. Most of the others have some possibility of substitution, but for the soil there is no substitute. The forest burned to destruction can rise again if the soil remains. Some examination will show that the most vital part of the whole conservation matter is the preservation of the soil, and that soil conservation is 99 per cent the prevention of erosion. Soil robbery by unscientific agriculture can go to its most extreme lengths and reduce the soil to the depths of non-productivity; but scientific agriculture can, by the addition of humus and some fertilizer, soon restore such soil to high fertility. In these conditions of exhaustion the loss to fertility by soil leaching is small, because of the non-soluble character of the earth particles. Thus experiments at Cornell have shown that in the average foot of top soil from rather unproductive farms in a low state of production, there was plant food sufficient for 6,000 crops of corn. We have all seen a single thunder shower remove from a hillside corn field the fertility adequate for the making of a hundred crops of corn.