848 F.XPF.RT^rF.NT STATION RECORD. 



barrier to further growth. If. however, the fiiii>,'iis attaeks the host cells when 

 thej' are nearly mature, it finds conditions more favoral)le to its develoinnent 

 and the rt'sult is a more vifiorous unnvth of the fungus and a rapid browning 

 and drying of the host tissue. 



Spraying with Bordeaux mixture has been demonstrated as a preventive of 

 the disease, and applications made in June or early in July are as effective as 

 those made earlier in the season. 



A"l)rief I)ibliograiihy of the literature of this disease is given. 



The apple-tree canker or black-rot fungus in South Africa. I. P.. P. Evans 

 (Trausnial Agr. Jour., 7 (l{)08), Ao. 2.j. />/». 62-(i.'i, pi. 1). — Attention is called 

 to the occurrence of Sijlurropfiis walorum on api»les from a number of districts 

 in Cape Colony. It is apparent that the fungus is rather widely distributed 

 and is causing considerable loss. The destruction of all decayed fruit, pruning 

 out of cankers, and spi'aying with Bordeaux mixture are recommended as 

 preventive measures. 



Die back of peach shoots, G. Massee {Roy. Bot. (iard. New, Bui. Mine. 

 Inform., 190S, Ao. 7. pp. 269-271, pi. 1; ahs. in Jour. Ron. Hori. Hoc. [London^, 

 SJf {1908), No. 2, p. 272). — The author states that during the past few years 

 numerous inquiries have been addressed to the Kew (Jardens resi)ecting the 

 die back of peach shoots. 



In the spring the leaf buds expand normally without any suggestion of the 

 disease, but about the time when the blossom is fully expanded the young 

 leaves wilt, turn bi'own, and die within a few days. At the same time the 

 petals change to a rusty brown color and the flowers droop, but remain attached 

 to the branches for some time, as do also the leaves. Finally the shoots assume 

 a deep claret-red color and shrivel more or less as the season advances. 



About midsummer, when the dead leaves and tlowers have been removed by 

 wind and rain, trees that have been badly diseased can be readily recognized 

 by the appearance of naked shoots varying from 1 to 2 ft. in length. If these 

 dead branches be examined during the months of May and June of the following 

 year they will be found to be more or less thickly studded with minute, dull- 

 orange-colored, tendril-like bodies, consisting of myriads of spores of a parasitic 

 fungus. This parasite has so far failed to produce any other fruiting form 

 than the conidia. and it has been identified as ywmospora crocea. 



Investigations have shown that the shoots are capable of infection only 

 when quite young, but that when the mycelium has gained entrance into the 

 tissues it spreads rapidly and affects the entire growth of the season. Success- 

 ful inoculation experiments have been made, but when branches more than 1 

 year old were inoculated no trace of disease was produced. The spores of the 

 fungus do not ajipear to retain their germinating power for more than 3 months. 



The citrus fruit rot, I. B. P. Evans (Transvaal Agr. Jour., 7 (1908), No. 25, 

 pp. 60-62, pi. 1 ) . — According to the author, considei-able injury is being done 

 to citrus fruits by the blue mold (Penicillium digitatum). A description is 

 given of the fungus and its method of attacking the fruits, and. on the basis 

 of information given in a bulletin of this Department (E. S. It., 20, p. 43), the 

 author urges care in the management of orchards and in the handling of fruit 

 in the course of preparation for market. 



The diseases of the tea plant, C. Maublanc {Agr. Prat. Pays Chauds, 8 

 {1908), Nos. 65, pp. 91-102, pi. 1; 66, pp. 227-2.1,1, pi. i).— A study is given of 

 the various diseases to which the tea plant is subject, the information being 

 largely drawn from notes of the late G. Delacroix. 



Among the diseases of the foliage described the most destructive are the gray 

 blight {Pestalozzxa gurpini), anthracnose (Collctotricltuiii rameUia'), blister 



