32 Forestry Quarterly. 



taken fresh from the delivery wagon and at once exposed to a 

 temperature of 131° F. (55° C.) until they crack open (that is for 

 about 20 hours long) preserve on the average only 7 per cent, 

 germination while the same cones preliminarily dried for several 

 days in rooms warmed from yy° to 86° F. (25° to 30° C.j and 

 then kiln-dried at about 104° to 122° F. (40° to 50° C.) for 6 to 8 

 hours and finally kiln-dried for a short time until they crack wide 

 open, in the hottest part of the drying-kiln at 122° to 131° F. 

 (50° to 55° C), showed (in the average of over 1,000 tests in the 

 year 1908-9) 87.6 per cent, germination (the maximum amount- 

 ing to 98.7 per cent.). From this observation the practice has 

 been developed for the Eberswalde drying-kiln of treating the 

 cones first dried in the preliminary drying-room (which unfor- 

 tunately is only a primitive one) for several hours in the coolest 

 part of the drying-kiln and then exposing them gradually more 

 and more, through constant transposition of the drying trays, 

 to the in-flowing hot air. In this way it has been possible, without 

 increasing the degrees of heat, to shorten the process in the 

 drying-kiln with a great increase of the germination per cent. 

 But it is especially dangerous that in the ordinary kiln-drying 

 establishments of the Prussian Forest Administration cooler and 

 warmer air must be let in by constant changes of the inlet valves 

 and with continuous observation of the thermometer, whenever 

 the temperature in the drying-chamber ascends over 131° F. 

 (55° C.) or threatens to fall below 113° F. (45° C), with the re- 

 sult that the air-valves must be handled every 8 to 12 minutes. 

 Every brief neglect makes itself felt through the whole contents 

 of the drying-chamber (about 45 bushels) (16 hi), resulting in 

 a great decrease of the germination energy. 



The often discouraging results of plantations (despite all la- 

 bor and care) have for a long time been correctly traced back 

 to careless and too severe kiln-drying of the seed with the con- 

 sequent weakening of its vitality ; the seeds will indeed germinate 

 if kept long enough (especially in germination testing apparatus 

 cleverly chosen and carefully attended to) ; but they can not 

 withstand unfavorable weather in the plantation and endure ex- 

 posure to the weather which stronger seeds (those, for instance, 

 released naturally or resulting from cone-sowings) vigorously 

 overcome. 



It can not be left unmentioned that in the tenth edition of 



