35 6 EXPERIMENT STATION RECORD. 



latter. The life histories of the fungi are described at some length, 

 their effect on the host plants are .stated, and the results of extended 

 investigations to ascertain the percentage of damage done are given. 

 The author concludes that about 6 per cent of the crop is annually 

 destroyed by these diseases. 



Investigations are reported on the effect of different times and 

 depths of seeding on smut infection. The investigations seem to indi- 

 cate that late planting tends to reduce the percentage of smut, while 

 broadcasting the seed gave the lowest amount of the disease. In the 

 case of seed broadcasted and lightly covered, the average amount of 

 smut was 2 per cent. Seed covered to a depth of 1 in. averaged 6 per 

 cent; 4 in., 10 per cent. 



Investigations for the control and prevention of smut showed hot 

 water and formalin proved the most ethcient of the means tested. 

 The author thinks the best procedure in most cases would probabl}^ be 

 to treat onh' enough grain to obtain clean seed for another year. 



Smid of tall oat ^yY<.s'.y (pp. 816, 317). — This smut ( f7! j-^'^re^manx) , 

 which was formerly thought to be identical with that of oats, is said to 

 be less destructive to the flower parts of the grass than the loose smut 

 of oats. The host plant of this species is not ver}- common I3" grown 

 in Illinois, consequently the smut is of comparatively little importance. 



Loose and covered smuts of harleij (pp. 317, 318). — These 2 smuts 

 {U. Jwrdel and U. nuda) have been until recently considered the same 

 species, the general appearance leading to this supposition. Both 

 forms gain entrance to the host through the young tissues of the germi- 

 nating seed. It has been shown that the spores falling between the 

 open glumes are the chief source of infection and it is thought likeh' 

 that with the loose smut the spores germinate and infect the seed coats 

 with a hibernating mycelium which produces the disease the next 3'ear. 

 On this account ordinary methods of treatment will prove failures. 



Loose smut of wheat (pp. 318, 319). — This smut ( U. tritlci) is closelv 

 related, as its life histor}" shows, to the smut of barley. An investiga- 

 tion by the author showed in 2 fields losses due to this source of 6 and 

 15 per cent, respectively. The author has conducted no experiments for 

 its prevention but, based upon other recommendations, he suggests soak- 

 ing the seed ■! hours in cold water, letting it stand 1 hours more in the 

 wet sacks, and then treating it with hot water (133' F.) for 5 minutes. 

 This treatment will probably kill some of the seed, hence about 1^ 

 times the normal amount should be seeded. 



Stinldng smut of wJbeat (pp. 319-321). — This characteristic smut 

 {Tilletia fastens) is comparatively well known and frequenth^ very 

 destructive. Hot-water treatment, as shown by experiments at the 

 station, proved A'ery efficient in its control. 



Srmit of Lndian corn and teosinte (pp. 321-335). — The snuit of these 

 2 plants infests the host on almost any part except the silk of the ears 



