MICHIGAN ACADEMY OP SCIENCE. 161 



THE RELATION OF THE STORAGE OF THE SEEDS OF SOME 

 OF THE OAKS ANT) HICKORIES TO THi:iK 

 GERMINATION. 



BY C. C. DELAVAN. 



The work described in the following paragraphs was carried on 

 dnring the winter of 1913-14 nnder the direction of Professor New- 

 combe at the Botanical Laboratories of the University of Michigan. 

 11 was desired to compare different methods of storing the seeds of 

 these two imi)ortant genera of Sonth-Michigan timber trees so as 

 best to retain their germinating ability. 



Three species of hickory — Carya glabra, ovata and cordiformis; 

 three species of the white oak gronp — Qnercns alba, macrocarpa 

 and bicolor; and two species of the black oak gronp^ — Qnercns 

 rnbra and velntina, were used in these experiments. These seeds 

 were collected from trees in the vicinity of Ann Arbor in October 



1913. At this time the seed of all eight species were thoroughly 

 ripe and most of the acorns had fallen. 



The seed of the white oak group, Quercus alba in particular, was 

 possibly not in the best of condition at the time they were col- 

 lected. Many of them had already germinated and it is possible 

 that some of those not germinated had failed to do so from lack of 

 vitality. 



The seed of each species was divided into four equal parts. Otie 

 part was placed in glass fruit jars and put in a pit about one foot 

 under the surface of the ground. The minimum temperature reached 

 in this pit was -5° C. and the seeds placed there had, on April 1, 



1914, a moisture content, in per cent of their weight, of 10 to 40. 

 The relative humidity in the pit was fairly high. 



A second part was placed in closed, but not sealed, fruit jars 

 and placed in the ice box of the Homeopathic Hospital. The tem- 

 perature here varied between 1° and 8° C, the relative humidity 

 averaged about 95^ and the moisture content, in per cent of the 

 weight, was. on April 1, 1914. between 13 and 42, depending on 

 species. The moisture content of the seeds was, Avith one excep- 

 tion, higher than that of the seeds in the pit. 



A third part was weighed and then dried at a temperature less 

 than 40°r. until the seeds had lost about 5% of their original 



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