20 MASS. EXPERIMENT STATION BULLETIN 20,S 



of the soil ill tiic non-porous pots, but not in the porous pots. In the non-porous 

 container, the only place where evaporation can occur is at the soil surface. In 

 the porous pots, there is a greater loss of soil moisture through the wall of the pot 

 than from the soil surface. It thus appears that the soluble salts move in the 

 same direction as the moisture. Chemical analysis showed that, in soils in 

 clay pots, the disappearance of nutrients became successively slower from the 

 region near the pot wall to the center of the soil mass. In a porous or clay pot the 

 most extensive root development takes place near the inner surface of the pot; 

 while in a non-porous pot the root system ramifies throughout the entire soil mass. 



Diseases of Outstanding Importance in 1932. (O. C. Boyd and \Y. H. 

 Davis.) 



Cherry bacterial blight (believed to be due to Bactcvinni ccrasi F. L. Cyriffin 

 rather than B. priiui EPS.). 



Downy mildew {Pscudoperoiwspor-a ciibcusis (Berk, and Curt.) Rostew.) of 

 summer squash and Blue Hubbard winter squash. 



Anthracnose of watermelon caused by Collctotrichiiui lugciiarijun. (Pass.) Ell. 

 and Hals. 



Twig blight and canker of Junipenis sp. caused by Phomopsis sp. 



Bacterial spot of carnation caused hy Bacterium li'oodsii EPS. 



Peach scab caused by Cladosporium carpophUian Thuem. 



Pear scab caused by Venturia pyrina Aderh. 



Eire blight of pear, apple, and quince caused by Bacillus awylovorns (Burr.) 

 Trev., largely confined to yard trees and neglected orchards. 



Spur blight of raspberry caused by Mycosphaerella ruhina (Pk.) Jacz. on Her- 

 bert and other red varieties; anthracnose caused by Plectodiscella vcncta (Speg.) 

 Burk. on both red and black varieties; Mycosphaerella rubi E. \V. Roark, although 

 not unusually prevalent on foliage, caused severe girdling of bearing canes of red 

 varieties on Cape Cod. 



Gray mold rot of strawberry caused hy Botrytis cinerea Auct.; stunt, barrenness, 

 and early dying cf strawberry plants, apparently due to the disease, "dwarf" or 

 "crimps," caused by the nematode, Pathoaphelenchus fragariae . 



Bacterial wilt of cucurbits caused by Bacillus trachcipMlus EPS. 



Downy mildew of cucumbers and muskmelons. 



Wilt of winter squash caused by Mycosphaerella citndlina (C. O. Smith) Gross. 



Early blight of celery caused by Cercospora apii Presen. 



I^ean Blights caused hy Bacterium phaseoli EPS. and 5. mcdicaginis phaseolicola. 



Downy mildew of onion {Peronospora schleideni LTng.). 



Mosaic of tobacco. 



Cytospora canker of Blue and Norway spruces, caused by Cytospdra sp. 



Peony blight caused hy Botrytis paeoniae Oud. 



Hollyhock rust {Puccinia malvacearum C. G. Bertero). 



Delphinium black spot caused hy Bacterium delphinii (EPS.) ikyan. 



Tulip blight caused hy Botrytis tidipae (Lib.) E. V. Hopkins. 



Rose black spot caused by Diplocarpon rosae Wolf, and powdery mildew, 

 Sphaerotheca pannosa (Wallr.) Lev. 



Iris rhizome soft-rot caused hy Bacillus carotovorus L. R. Jones. 



Bacterial wilt of sweet corn, caused by Aplanobacter stewartii (EPS.) McC. 



Smut, Ustilago zeae (Beckm.) Ung., caused more loss to corn than all other dis- 

 eases combined and appeared to be more damaging than in the average season. 



Late blight of tomatoes, caused by Phytophthora injcstans (Mont.) DeBary, 

 which ordinarily causes very slight or no damage in Massachusetts, assumed 



