446 EXPERIMENT STATION RECOEti. 



Pierce, Tex., on Ct/perus tcgetifonnis, a Chinese species of sedge introduced 

 for use in the matting industry; witches" broom of bamboo (LocuUstronia 

 bambus(e n. g. and sp. ), forming sclerotia-like bodies similar to those of 

 Claviceps purpurea at the nodes of a bamboo (PhyUostachys sp.) from Hankow, 

 China ; a peony disease caused by Botrytis pceonice; a chrysanthemum disease 

 due to B. cinerea; a disease of cyclamen caused by Glonierella rufomaculans 

 cyclaminis n. var. ; and a Stemphylium {8. citri n. sp.) on oranges in Arizona. 



In the second paper, Pineapple Rot Caused by Thielaviopsis paradoxa, the 

 results are given of a series of experiments on pineapple rot. This disease so 

 reduces the profits of shippers as to be in a sense prohibitive to the transpor- 

 tation of fruit from sonie localities. The methods of checking this disease by 

 fumigation with formaldehyde gas are described. It was found that from 

 1,200 to 1,300 cc. of formalin per 1.000 cu. ft. of air space was fatal to T. para- 

 doxa when used in an air-tight compartment at a temperature of 65 to 80° F. 

 and a humidity of 3S per cent for 30 minutes or more. The formaldehyde gas 

 was liberated by pouring 40 per cent formalin on potassium permanganate at 

 the rate of 100 cc. of formalin to 50 gm. of permanganate. 



Report of plant pathologist, H. S. Fawcett (Ftorida Sta. Rpt. 1909, pp. 

 XLVI-LXII, p(js. 6). — The investigations for liJOO were mainly confined to the 

 scaly bark {Hormodcndron sp.) and other diseases of citrus trees. 



By cultures and inoculation tests on young orange trees, the initial cause of 

 the disease was found to be a fungus belonging to the genus Hormodendron, 

 but extended observations seem to indicate that withertip fungus (Collcto- 

 trichum glocosporloides) associated with the Hormodendron as a secondary 

 agent caused most of the injury from the disease. It was found that the main 

 period of infection was between June 1 and December 1, which corresponds 

 fairly well to the rainy season in Florida. 



The disease rarely appears on twigs less than 6 months old, and is most 

 severe on wood 9 to IS months old. On the fruit it first api^ears about 4 or 5 

 months after the bloom has been shed. 



To control the scaly bark 4 principal lines of treatment were tested, viz, (1) 

 spraying with Bordeaux mixture, (2) pruning, (3) heading back and painting 

 with carbolineum, and (4) spraying with dilute solutions of carbolineum. The 

 results of the experiments with Bordeaux mixture (5:5:50), together with 

 observations as to the time of greatest Infection, indicate that 3 applications 

 would be quite effective in preventing the fruit from spotting, and would ma- 

 terially lessen the injury to the limbs of the trees. The first application should 

 be made just before the blooms open, the second after the fruit is fairly set, 

 and the third in the latter part of July or early August. It was also found 

 that one thorough spraying with the Bordeaux mixture in November dimin- 

 ished the quantity of spotted fruit during the following year. 



After heading back by cutting out the tops, leaving only the trunks and 

 stubs of the larger limbs, and the removal of all foliage and small suckers, 

 the entire surface of the bark was painted over with a 1 : 1 mixture of carbo- 

 lineum and soapy water, which treatment produced very satisfactory results 

 in controlling the disease. The pruning out of all dead wood and badly dis- 

 eased branches was clearly beneficial in lessening the sources of infection dur- 

 ing the first year, but the disease gradually came back into the trees thus 

 treated. 



Attention is called to, and remedies suggested for, gummosis and scab (Clad- 

 osporium citri) of citrus trees; buckskin of grapefruit and sometimes of sweet 

 oranges; white rust {Peronospora parasitica), stem rot of seedlings (Corticium 

 vagum solanl), leaf spot (Alternaria brassica;), .and black rot {Pscudomonas 

 cumpcstris) of cabbage; mildew {Micrbsphwra euphorbia) on cowpeas; and 



