In 1896 a peculiar stem-trouble was noted in Ohio affecting primarily nursery-stock and the twigs of older orchard trees. Two years later it was described, and was called constriction disease, or stem blight. It has subsequently been reported from Connecticut and New York on seedling peaches. The affected twigs are partially or completely girdled by a cankerous formation. The parts above the lesion do not die immediately, but eventually they succumb, as evidenced by a yellowing and a premature defoliation. Just above the canker a swelling of the stem occurs, resulting in a constricted appearance. Scattered over the canker will be found numerous pycnidia of the fungus which show as black specks. The pathogene develops best on trees in a weakened condition, and for that reason the careful grower may expect that the trouble will never be of great consequence.
Selby, A. D. Preliminary report upon diseases of the peach. 7. Constriction disease of stem and branch. Ohio Agr. Exp. Sta. Bul. 92:233 - 234. 1898.
Clinton, G. P. Notes on plant diseases of Connecticut. Peach. Stem canker, Phoma Persicos Sacc. Connecticut Agr. Exp. Sta. Rept. 1912: 351 - 352. 1913.