260 ANNUAL REPORTS OF DEPARTMENT OF AGRICULTURE. 



land, 373,000 acres; in Illinois — Albion, 338,000 acres; Richland, 

 21,000 acres. Relatively smaller acreages are grown in adjoining 

 States. These acreages, particularly that of the Albion, have been 

 doubled or perhaps trebled since 1919. The two newer improved 

 varieties, lowar and logren, continue most promising, the lowar 

 outyielding the Albion by a few bushels per acre. The logren, a 

 selection from the Green Russian oat first distributed to farmers 

 of northern Iowa in 1921 and further distributed in that section in 

 1922, showed marked superiority in yield over the common unse- 

 lected stocks of the parent variety. 



CORN. 



Investigations have shown various parasitic and semiparasitic 

 bacteria and fungi important in causing root, stalk, and ear rots. 

 In addition to the bacterial wilt, or Stewart's disease, caused by 

 Aplanohacter steivartii (Smith) McCulloch, and bacterial root and 

 stalk rot caused by BacteHum dissolvens Rosen, what appears to be 

 a new bacterial disease is being investigated. The principal fungi 

 which have been found to be aggressive parasites are Diplodia zeae 

 (Schw.) Lev., C&phalosporhim acremonium Corda, and Gihterella 

 saubinetii (Mont.) Sacc. Fusarium moniUforme Sheldon often is 

 found associated also, but this fungus does not seem to be aggres- 

 sively parasitic on healthy corn. Other fungi also are being studied, 

 but as yet their relations to disease causation have not been deter- 

 mined. It has been found that Diplodia and Cephalosporium seem 

 to be the most important of the fungous parasites of corn in this 

 complex. These fungi \n?ij attack corn plants separately and each 

 cause important reductions in yield, or in some cases they are found 

 associated on the same plants, when the losses are aggravated. In 

 the case of the disease caused by Diplodia, it has been found that 

 comparatively high soil temperature together with high soil moisture 

 during the seedling stage of the corn plant favors infection and 

 results in the greatest reduction in yield. In experimental plats 

 Diplodia was found to cause as much as a 34 per cent reduction in 

 yield. As a result of laboratory studies on Fusarium ononiliforme, 

 the ascigerous stage of this fungus has been developed in artificial 

 culture. 



In addition to the development of resistant varieties, the indica- 

 tions are that the control of the entire group of root and stalk 

 rots will require special soil management. Where the nonpara- 

 sitic tj'pes occur by themselves, apparently the proper fertiliza- 

 tion and amendments are sufficient. Where the parasitic types are 

 concerned, especially the fungous parasites, careful consideration ap- 

 parently must be given to crop rotations as well as to fertilizers and 

 amendments. 



FORAGE CROPS. 



New grasses for the Southeast. — The value of molasses grass for 

 Florida and the immediate Gulf coast is now well demonstrated, and 

 efforts are being made to induce seedsmen to carry supplies of seed, 

 which have to be imported from Brazil. Dallis grass {Paspalum 

 diJatatum) and Bahia grass {Paspalum notatum) are proving to 

 possess great value for the Southeast, but difficulty is experienced in 

 obtaining satisfactory seed supplies. The seed of the former is im- 



