Excerpts: The research study, made by the Department of Agriculture to determine the effects that utilization of maleic hydrazide on tobacco for sucker control has upon the leaf produced for cigarette manufacture, shows that this chemical changes the chemical and physical properties of the leaf. The changes as to the physical effects on U.S. cigarette leaf suggest severe economic repercussions. The loss of filling capacity alone threatens to substantially reduce the sale of U. S. leaf for economic reasons in such very high duty countries as Great Britain and Ireland, which together took 43 percent of U. S. flue-cured leaf exports in 1960. It would also reduce the competitiveness of U. S. leaf in other countries. A decrease in consumer smoking preferences because of the effects of maleic hydrazide in association with other questionable changes in tobacco, would decrease export demand for U. S. leaf as soon as competitive foreign production can furnish the necessary volume. A successful tobacco support program rests upon human ability to readily identify and classify leaf suitability for the making of a consumer preferred product. This is becoming exceedingly difficult to do in an adequate fashion. Unknown factors caused by genetic crossbreeding and chemical additives, including the use of maleic hydrazide are making all known classification systems of little value as leaf suitability measurements.