Excerpt from Diseases of Field and Vegetable Crops in the United States in 1923 The most outstanding observation of the season is undoubtedly the al most entire absence of potato late blight in all the mayor potato producing states if the country. At one time there was consideranle Phytophthora ig festans on the potato foliage in Florida, but the economic loss from rot from this source was very minor. His is an illustration of the dependence of crop diseases, as wall, as the crops themselves, upon the conditions of environment under which they are grown. This point may be further illustrated by the con Siderable loss from downy mildew caused by Peronospora effusa which occurred in Connecticut, Long Island, and New Jersey trucking districts following the excessive rains the first week in June. Eafter the rain the spinach tissues Were soft and conditions highly favorable for rapid growth and Spread of the fungus. The conditions of temperature and light as well as moisture are im portant in determining whether a disease will develop from minor to major propor tions or the reverse. Goss of Nebraska reports that potato mosaic was made evident in early season by heavy rainfall, low temperature, and deficient sun light, while following mid-summer conditions there was little mosaic to be seen. The various Fusarium diseases have long been associated With nigh temperature, while tobacco black root rot is favored by cool conditions. 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.