10 EXPERIMENT STATION RECORD. 



5 Hard seed.— The hard seed of legumes and nongerminated seed of 

 very slowly germinating tree seed, which prove viable on being cut 

 open, are given in a special column as "bard." Other seeds which 

 have not germinated are given as "dead." The germination of beet 

 seed is calculated in percentage of viable bolls. 



The proportion of hard seeds in seed of leguminous plants has been 

 determined at the Danish seed-control station since the summer of 1874. 

 Experiments in the open held having shown that about half of the hard 

 seeds germinated during the summer, the percentage of germination is 

 increased by one-half the percentage of hard seeds. Since 1887 the per- 

 centages of germinated and hard seeds have been given separately in 

 the analysis certificates, and according to common usage in Denmark 

 the viability of a sample of leguminous seeds has come to mean the 

 sum of the germinated and hard seeds. In the other Scandinavian 

 countries and in Finland only one-third of the hard seeds are as a rule 

 considered viable. 



A greater proportion of hard seeds is found soon after harvest than 

 later on, the proportion decreasing somewhat in the course of the winter. 

 The samples of red, white, and alsike clover analyzed at the Danish 

 station during the year 188G-87 contained on an average the following 

 percentages of hard seed: November, 1G per cent; December, 12 per 

 cent; January, 10 per cent; February, 9 per cent; Marcb, 9 per cent; 

 April, 9 per cent; and May, 9 per cent. 



The germinative ability of hard seeds increases with age, but the 

 method of keeping the seed has a marked influence, a dry, warm atmos- 

 phere being favorable to the preservation of their hardness. 



Where the proportion of hard seeds approaches 20 to 30 per cent or 

 exceeds these figures, as is often the case with white and alsike clover, 

 the matter of hard seeds becomes one of great importance. Under 

 ordinary conditions and with other leguminous seeds the depreciation 

 from this cause is considerable. 



Efforts have been made to prepare hard seed so as to secure perfect 

 germination, but they have not been altogether successful until lately. 

 The seed-coat crusher (fropraparator) constructed by K. Hj. Mlsson, 

 director of the Svalof seed station in Sweden, maybe said to have prac- 

 tically solved the problem. The seed crusher consists of an emery cyl- 

 inder, which is rotated at the rate of 3,200 revolutions per minute. 

 The .seed passing through the machine is thrown against tbe cylinder 

 and its seed coat scratched so as to readily permit the entrance of 

 water to the germ of the seed. 



The earlier form of the machine worked in a satisfactory manner, but 

 its capacity was too small, viz, only one to one and one-half bags of 

 seed (100 to 150 kg.) per day. The machine as now perfected and 

 manufactured has a capacity of 100 to 200 kg. per hour, according to 

 the kind of seed treated. The price of the seed machine, which is 

 patented, is 300 crowns ($81). The treatment by the process has been 



