VITALITY OF MUSHROOM SPAWN. 59 



oTowing is attributable to tlie injury suffered by the spawn after its 

 ]3reparation. Tliis conclusion has been further strengthened by the 

 experience of the past three years. From Table VIII, beds Nos. 1, 

 2, 4, 5, and 30, it will be seen that, under conditions where fresh spawn 

 has invariably made a good yield, the spawn which is more than a 

 year old is, for the most part, seriously injured or killed. To be 

 exact, in only one case was there any production of mushrooms by 

 spawn which had been kept for a year or longer. It must be said that 

 no attempt was made to keep these spawns under similar conditions or 

 under the most favorable conditions. For the most part the sjDawn 

 was stored in the dry laboratory room, in which the temperature was 

 more or less variable, but ncA'er extreme. The old American spawn 

 which was used in experimental bed No. 1, in Tal)le VIII, was stored 

 in a l)asement room where the average temperature Avas undoubtedly 

 cooler than that of the laboratory room. 



From experimental beds Nos. 1, 3, 4, and 5, in Table X. it is again 

 seen that old spawn is unreliable. In this particular case the mate- 

 i-ial was furnished by a prominent mushroom grower — ^an English 

 spawn importer. This spawn had been stored in a dry house and 

 was therefore subject to similar conditions. In Table VIII, beds 

 Nos. 31, 32, 35, and in Table IX, Nos. 34, 41, and 45, there is further 

 j)roof of the loss of vitality in the imported spawn ordinarily off'ered 

 for sale in many of our cities. In these cases spawn was bought on 

 the market just as offered for sale to the amateur buyer; "best on 

 hand " was asked for, but no stipulation was made that is should be 

 of recent importation, and no guaranty was asked. The tests were 

 not, therefore, to compare the very best English with the best Amer- 

 ican spawn, but merely to, secure an indication of some of the cause's 

 of failure by the purchase at random of English and French spaAvn 

 on the market. Even in times past the extensive mushroom growers 

 have either imported their spawn direct, or made sure that they 

 Avere obtaining the best product that the market could furnish. 

 Unfortunately, it has not been possible to compare, in any exj^eri- 

 ments thus far concluded, the best English with the best American 

 spawn. 



The results seem also to indicate that brick spawn maintains its 

 vitality longer than the flake material, and that brick spawn made 

 of loose, light material is less retentive of vitality than that made 

 after the formula commonly followed in England. This proves to 

 be an inifortunate factor to be dealt with in the attempt to reduce 

 by all means the weight of the brick. The reduction in weight 

 would be most desirable, since freight upon this material adds con- 

 siderably to the price of market spaM^i. To the poor keeping quali- 

 ties of loose spawn is perhaps due the large number of failures w4th 

 French flake spawn, and perhaps also some of the failures with the 



