Agricultural Research lx New Hampshire 49 



is some doubt as to the economy of using very much nitrogen in pastures 

 where Ladino forms a considerable portion of the stand. 



Competition of each of the grasses with Ladino is being studied in 

 those pastures in which Ladino still persists. Estimates indicate that reed 

 canary grass offers the most competition, tall fescue second, and orchard 

 grass third. Smooth brome, timothy, and perennial rye follow in this 

 order but are quite similar in this respect. 



Two of the pastures that are being studied contain plots on which 

 orchard grass has been seeded at different rates In one instance, 3, 6 and 

 Q pounds per acre were seeded, whereas, in the other, 5 and 10 pounds 

 were used, with uniform Ladino in both cases. 



At the end of 1944, there was 5 per cent more Ladino in the two 

 lighter seedings than on a heavier orchard grass seeding, but there was 

 no observable difference in percentage of Ladino or orchard grass in an- 

 other instance. 



Three comparisons are available in which yields of large grasses with 

 Ladino may be contrasted with complex commercial pasture mixtures. 

 The data show an advantage in yield for the simple mixtures as compared 

 A\ith the complex pasture mixtures in which several grasses are used with 

 Ladino clover. Stand estimates indicate that red top and Kentucky blue 

 grass, both sod forming, occupy too much of the stand within a year or 

 two in the case of complex mixture areas. These two grasses are not high 

 yielding and afford too much competition with the Ladino clover. They 

 also tend to crowd out the timothy under grazing conditions. With less 

 productive species occup\'ing the sward a lower yielding and less palatable 

 pasture will result. 



F. S. Prince, P. T. Blood, G. P. Percival 



PLANT PATHOLOGY 



Control of Tomato Diseases 



Three phases of the tomato-disease problem were investigated dur- 

 ing 1944-45 as follows: 



1. Late blight. Continuing the work started two years ago, sev- 

 eral more varieties of tomatoes were obtained and tested for resistance 

 to Fhytophthora infestans. None of the many selections obtained and 

 inoculated so far have shown immunity to the late blight pathogen. 



2. Spray treatvients. Three fungicides. Copper oxychloride sul- 

 phate, Bordeaux mixture and Fermate, were used, in 1944, on tomato 

 plants of the New Hampshire Victor variety for the purpose of deter- 

 mining their effect on the control of Alternaria blight. The total vield of 

 fruits per plant was not significantly increased by Copper oxvchloride 

 sulphate or Fermate. The yields were actually decreased by applications 

 of Bordeaux mixture. However, a significant increase in marketable 

 fruits was obtained by the use of the three materials and at all concentra- 

 tions. Defoliation was high in all cases at the end of the season, Septem- 

 ber 7, but defoliation was sufficiently retarded to permit the production 



