262 A>s"NUAL, REPORTS OF DEPARTMENT OF AGRICULTURE. 



Tests have been conducted in various Southern States for the pur- 

 pose of studying its resistance to the attack of the Mexican bean 

 beetle and to obtain definite information of its yield of forage and 

 seed as compared with other crops. 



Vetches. — The testing of a large number of vetches at many points 

 in the South has indicated the conditions to which the various spe- 

 cies are best adapted. The woolly podded vetch continues to show 

 its superior value for the Southern States because of its vigorous 

 winter growth and its comparative resistance to the disease caused 

 by Protocoronospora nigricans. Investigations have continued with 

 purple vetch, and the seed-growing area of this species has been ex- 

 tended in California and Oregon. This vetch is especially well 

 adapted for use as a green-manure crop in citrus orchards in Cali- 

 fornia. It now appears that a source of seed has been permanently 

 established. Excellent results are still being obtained from Hun- 

 garian vetch (Vicia pannonica). It is thought that this crop will 

 be of much value, especially on wet clayey soils in the Pacific North- 

 west. 



/Sweet clover. — The utilization of sweet clover has been studied in 

 the field and in cooperation with the North Dakota Agricultural 

 Experiment Station. This crop is making a place for itself as one 

 of the most reliable summer-pasture plants. Selection work is 

 going on at our station at Redfield, S. Dak., where a new species of 

 yellow-flowered sweet clover that gives promise of usefulness is be- 

 ing grown. 



Bed clove7\ — The chief line of study of red clover has again been 

 that of the various strains from foreign countries. The following 

 State experiment stations are now cooperating in this work: New 

 Jersey, Maryland, Virginia, Tennessee, Kentucky, Missouri, Pennsyl- 

 vania, Ohio, Indiana, Michigan, Wisconsin, Minnesota, Iowa, Idaho, 

 and Oregon. Seed has also been furnished the extension service in 

 New Hampshire and New York. 



Results so far as Italian seed is concerned in the main have been 

 like those of previous years, showing that crops winterkill easily or 

 suffer after the first cutting, and in the future more emphasis will 

 be placed on the work with French and Chilean seed. 



The stem nematode. — The nematode that infests certain bulbs as 

 well as the stems of clover, alfalfa, and strawberries has increased in 

 importance as a parasite in the Northwestern States. In the large 

 irrigated clover-seed producing sections of southern Idaho it has 

 seriously affected yields ; it has been found severely attacking alfalfa 

 at several places in Oregon and Washington and is known to be 

 present at one point in California and one in Colorado. The indi- 

 cations are that this pest would be a menace to alfalfa if it should 

 become generally prevalent in the irrigated regions where alfalfa 

 is grown as a main crop, as observations and experiments have shown 

 that it is spread rather rapidly in the field by drainage water and 

 other agencies and may be distributed widely in the hay cut from 

 diseased fields. The disease does not usually become serious the 

 first year, but develops to such an extent by the third year that in- 

 fested fields are rendered unproductive and have to be plowed up. 



Several annual crops are known to be susceptible to this nematode, 

 and wild hosts have also been found in both the western and eastern 

 sections of the country. Studies of biological strains have indicated 

 that it is possible for one strain of the nematode to adapt itself 



