Excerpt from Report of the Director of the New Hampshire Agricultural Experiment Station for the Year Ending June 30, 1921 The question of seed certification was also given attention, and the ads vantages of producing certified seed rather than ordinary Stock were brought prominently to the attention of growers of seed potatoes. Potato Spraying Experiments. In one experiment to determine the effect of pressure on the protection afforded by Bordeaux mixture, Mr. Butler found that, when the pressure used was reduced from 180 pounds per square inch, to 90 pounds per square inch, the protection afforded was reduced one-half. The mixture applied under 180 pounds pressure was more thor oughly distributed over the plants than that applied under 90 pounds pres sure; and this probably accounts almost wholly for the better protection afforded, since the amount of copper applied per acre on doubling a given pressure is not increased by one-third. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.