Science: Plant Fever

Sick plants are like sick children. They get hot and feverish when they don’t feel well. Last week the University of California’s Professor C. E. Yarwood told how he put leaves of healthy plants in a well-insulated container and measured their temperature after four hours. He found that the respiration of the leaves (their “breathing” of oygen) had raised their temperature at most 2.7° F. above the outside air. Then he put sick leaves, infected with virus or fungus diseases, in the chamber. In four hours they were running temperatures up to 6.3° F. Sick leaves, Dr. Yarwood believes, breathe more oxygen than healthy ones, and the added oxygen brings on the fever.