146 EXPERIMENT STATION EECOED. 



solution, when the fungus was destroyed because the spray killed all the twigs 

 on the tree, both diseased and healthy. Of the summer sprays used, iron sul- 

 phid was the only one giving any promise of controlling the mildew under the 

 conditions as found in the Pajaro Valley. The first iron sulphid spraying for 

 mildew should be applied along with the calyx-cup spraying for the codling 

 moth, and, of course, will contain arsenate of lead ; this requires that the 

 sulphid precipitate should be carefully washed to free it from soluble sulphur. 

 For this spraying, 10 lbs. of iron sulphate ])recipitated with lime-sulphur solu- 

 tion should make 100 gal. of spray, to which G lbs. of arsenate of lead is added. 

 The second, as well as subsequent applications, should come after a 3-week 

 interval, and consists of 7 lbs. of copperas precipitated with lime-snlphnr solu- 

 tion and then diluted with 100 gal. of water. The third and fourth applications 

 consist of 5 lbs. of copper sulphate and 4 lbs. of lead arsenate to 100 gal. of 

 water. It is stated that this iron sulphid treatment will effect a practical con- 

 trol of the mildew under the existing conditions. 



It was found that when trees were sprayed with sulphur solutions they 

 acquired an immunity to sulphur injury if sprayed regularly, while a first and 

 a fourth spraying consisting of some form of sulphur mixture often caused 

 serious loss of foliage, and even fruit from the last spraying. Similar trees 

 given 4 successive applications of the sulphur mixtures at intervals of 3 weeks 

 showed no signs of sulphur injury. 



The occurrence of apple blotch in Ohio, W. O. Gloyer (Ohio Nat., 11 

 (1911), No. 6, i)p. 33.'f-336, fig. i ) .—Attention is called to the presence of this 

 fungus on the Baldwin, Ben Davis, Stark, Pippin, Smith Cider, and Rome 

 Beauty in several counties in Ohio. In one orchard of Pippins 90 per cent of 

 the fruit was blotched, a condition which was not uncommon with many of 

 the varieties named. The disease appeared on sprayed as well as on unsprayed 

 trees, and was due, it is claimed, to a lack of proper pruning, thereby permitting 

 successive crops of spores to be produced on foliage and fruit not reached by 

 the spray. 



A summary of various spraying experiments, O. S. Watkins {Kinmundy, 

 III, 1911, pp. 16). — In this paper, read before the Fifty-fifth Annual Convention 

 of the Illinois State Horticultural Society at Urbana, 111., February, 1911, the 

 author gives the results of spraying experiments with various fungicides and 

 insecticides conducted during the summer of 1910 in different parts of the State 

 of Illinois. 



Two lines of experiments are reported, one being demonstration experiments 

 designed to show the value of known fungicides and tried methods in renovat- 

 ing old orchards, etc., and the other consisting of detailed experiments intended 

 to answer questions as to the comparative value of different sprays, the use of 

 trade compounds, etc. In the demonstration experiment plats, all the fruit was 

 killed at the time of the second spraying by a severe cold wave. Of the orchards 

 used in the detailed experiments, all had their fruit killed by the cold wave, 

 except the orchard at Neoga which comprised 300 15-year-old Ben Davis apple 

 trees and 12 Grimes Golden trees. Bordeaux mixture, lime-sulphur mixtures, 

 copper ferrocyanid, several proprietary fungicides, different brands of arsenical 

 compounds, and black leaf "40," a tobacco decoction, were tested. Chemical 

 analyses of some 13 proprietary arsenical comix)unds and commercial lime- 

 sulphur mixtures, and tabulated data as to the tests of these various fungicides 

 and insecticides on both fruit and foliage, are given. 



The author concludes that self-boiled lime-sulphur possesses very little fungi- 

 cidal value in controlling apple scab and is not very adhesive, but was more 

 effective in controlling the scab and less injurious to the foliage than commer- 

 cial lime-sulphur mixtures. It is claimed that one application of a 4 : 4 : 50 



