116 



SEEDING AND PLANTING 



when the period of germination does not extend beyond 1 or 2 

 weeks. The blotters should be placed in a moderately shallow 

 dish and an average sample of the seed placed between them. 

 Free water should not come in contact with the blotters or the 

 seed will become overwet. They should, therefore, be slightly 

 raised above the water in the dish and strips of blotting paper or 

 flannel arranged to connect the blotters containing the seed with 

 the water below. The dish should be more or less completely 

 covered, depending upon the humidity of the surrounding air. A 

 suitable temperature should be maintained and water added from 

 time to time. One advantage of this test lies in the ease with 

 which the progress of germination can be observed at any time 



by simply removing 

 the upper blotter. 



27. Germination 

 Tests on Plates of 

 Porous Clay or 

 Plaster of Paris. 

 A variety of forms of 

 porous clay plates 

 for testing the ger- 

 mination of tree 

 seed are in use. The 

 water is conveyed 

 to the seed through 

 the porous plate. 

 An impervious dish 

 is partially fi 1 1 e d 

 with water and the 

 porous plate upon which the seed is distributed is placed in the 

 former so that the water comes in contact with its lower surface 

 only. The water reaches the seed in ample quantity to induce 

 germination by soaking through the plate. A bell jar or glass 

 plate controls the loss of moisture through evaporation (Fig. 19). 

 Porous germination dishes made of plaster of Paris are superior 

 to clay plates in porosity. 



Stainer's germinating apparatus figured and described by 

 Eberts 1 has been tested by the author with satisfactory results. 



1 Eberts, E.: Zwei neue Keim-Apparate. (Allgemeine Forst- u. Jagd- 

 Zeitung, S. 371-372. 1884.) 



H : ; 



7M- 



FIG. 19. An improvised germinating apparatus. 



A. Complete. 



B. Cross section. 



a. Impervious dish. 



b. Porous plate. 



c. Glass cover. 



d. Water level. 



