ANNOUNCEMENTS OF IMPORTANCE 
TO ALL EXPERIMENTERS. 
During the past two years Joseph F. Rock has been traveling in 
Yunnan, China, where he has col 1 errfced many rare *nd beautiful specter 
of Rhododendron . Seeds of these have just been received at Washington, 
and are ready for distribution to experimenters who desire to test them. 
-Vhh collection contains many distinct- species and varieties: It 
is, Without doubt, the most extensive which has ever been secure<JFfrom 
that '{art of the world. In forwarding it, Mr. Rock wrote, T made- a - 
spec fal effort to get as many -as possible. They are really wonderful. 
You have no conception of the variety; some form dense mats over acres 
of ground, the whole one mass of rich crimson. Do not think of them 
as shrubs with flowers of various shades of pink; each one has an indi- 
viduality of its own, and they should prove an endless stock for the 
breeder. " 
Some of these plants come from elevations, of five or six thousand 
feet; some from much higher regions. Those which Mr. Rock secured on 
mountain passes at elevations of twelve thousand feet, where snow covers 
the ground for considerable periods annually, are likely to prove fairly 
hardy. Others will probably not succeed where winter temperatures lower 
than twenty wbove zero are experienced. There are regions on the Pa- 
cific slope, as for example the cool, moist coast of southern Oregon 
and northern California, where many of these rhododendrons ought to 
luxuriate. It is doubtful if any of them are sufficiently hardy for 
New England. The mountainous regions of the Caroltnas and other south- 
ern states may provide satisfactory conditions. 
If you have soil which has proved suitable for rhododendrons in 
general, and are equipped to handle the propagation of such plants, we 
will be glad to forward seeds of Mr. Rock's varieties for you to try. 
Since they will not be included in the general distribution next winter, 
these seeds can be sent only to those Who apply for them immediately. 
This number issued July 1924. 
