2 SEEDS AND PLANTS IMPORTED 



the ground nearly every year as far south as the Carolina*. Then, 

 too, there must be taken into consideration the length of day, the 

 atmospheric pressure which affects the amount of oxygen and carbon 

 dioxid in the air, and the effect which high mountain atmosphere 

 has upon the actinic rays of the sun. In other words, it should 

 never be forgotten that these plants are essentially cosmic machines 

 run by the sun's energy and that in no two places on the globe do 

 identical atmospheric conditions prevail. 



Twenty-five years of experience has taught those of us who have 

 been establishing new plants in America to be very cautious in pre- 

 dicting where plants will thrive, for no one can foresee except in a 

 general way the degree of accommodation which any new plant will 

 exhibit. The only way to find out is to test it, and Mr. Rock has 

 sent in large quantities of seeds for trial. 



Exploring alone in any country has its shady side, but in Yunnan, 

 where the explorer may at any time meet bands of roving bandits 

 and be subjected to the barbarities which only savages know how to 

 inflict, Mr. Eock has had to meet conditions which have been almost 

 unbearable. 



This fact should be borne in mind by those to whom in the years 

 to come these plants are sent for trial, and their value should be 

 measured in terms of the dangers and hardships which they have 

 occasioned. That Mr. Rock has been able to hold out and keep mov- 

 ing to America a stream of seeds and cuttings is the wonder of his 

 friends. 



One of the reasons for Mr. Bock's expedition to Yunnan was to 

 discover what species of chestnuts grow there and secure their seeds. 

 In this quest he has been successful. 



On the summit of the Salwin Ridge, southwestern Yunnan, Mr. 

 Rock found dense forests of a large species of chestnut {Casta nea 

 sp. ; No. 56080) which grows to be 100 feet tall and 5 feet in diam- 

 eter and bears sweet edible nuts the size of chinquapins. It is an 

 excellent timber tree, ratoons freely from the stump, and no evidence 

 of any disease was found upon it. Four days' journey west of 

 Talifu he found a small forest species, only 60 feet tall (Casta neq 

 sp. ; No. 56119), also with small nuts: and a tall species near Tali 

 Lake which bore deliciously sweet nuts (Castanta sp.; Xo. 55981). 

 Whether out of these species or others which he has collected will 

 come one which will solve the chestnut problem is a question which 

 will require years to answer. At any rate the first step — that of 

 getting together the Asiatic chestnuts — has been taken. 



From the discovery by Mr. Rock of numerous distinct species of 

 wild apples growing in the mountains far removed from civilization, 

 it would appear that western Yunnan is the region from which to 

 get southern forms of this fruit with which to build up by hybridiza- 

 tion an apple for our Southern States which now lie below the apple 

 belt. This collection includes fruits varying from the size of cher- 

 ries to those of large-sized crab apples. Some are trees 10 feet high, 

 growing in hot, dry. rocky locations where little else besides the 

 Yunnan pine grows, and others have long drooping branches. Nbrie 

 of these has as yet been determined botanically. 



Wild as well as cultivated peaches also occur in western Yunnan. 

 and Mr. Rock reports there a clingstone white-fleshed pouch 



