Next in order of seriousness among the diseases which attack cultivated plums is the brown-rot[157] (_Sclerotinia fructigena_ (Persoon) Schroeter) known also very commonly as the ripe-rot and sometimes as peach-blight. The disease is most conspicuous on the ripe fruits of the various drupes and is popularly supposed to be confined to the fruits alone. Such is not the case, for it also attacks, and very vigorously oftentimes, the flowers and shoots. The presence of the disease on the fruits is known by a dark discoloration of the skin which is afterward partly or wholly covered by pustule-like aggregations of grayish spores. The decayed fruits may fall to the ground, or as is more usual in the case of plums, they hang to the tree and as the juice evaporates become shriveled mummies, each mummy being a storehouse of the fungus from which infection spreads the following season. The twigs, flowers and leaves are known to be suffering from inroads of the parasite when they are blackened as if nipped by frost. In warm, damp weather the rot spreads with great rapidity and fruits touching in clusters or in boxes stored for shipping are well placed to spread the epidemic. Destruction of the mummy-like fruits and all other sources of infection, and spraying with bordeaux mixture are now practiced as preventives, but so far as the crop is concerned with but indifferent success. A better remedy than we now have is eagerly looked for by growers of fruits. The hosts of this fungus show varying degrees of susceptibility to it, the peach and the sweet cherries being more subject to it than plums. Similarly, among plums some species and varieties are more susceptible than others. Thus the Trifloras and Americanas, the latter especially in the South, are injured more by the brown-rot than other species. The idiosyncrasies of varieties in this regard are best shown in the discussions of the individual sorts.