14 Urea ON GARDENS 

INTERMISSION 
ocky Moun’taIn plants may be divided in two main groups 
for convenience in describing conditions under which they 
grow in their habitat. The first comprises Alpines, plants 
found near timberline and on up to the tops of the highest peaks. 
The second group comprises plants from the high dry plains, 5,000 
to 7,000 ft. elevation. 
ALPINE GROUP: 
About 12,000 ft. high on Pikes Peak are huge red granite boulders 
softened with silver-green lichen, their perpendicular crevices filled 
with complete and utterly satisfying gardens of Boykinia jamesii. 
At the base of these parent boulders are smaller rocks, tons of them 
broken loose, among which are ravishing alpine gardens: Mertensia 
coriaceae with bluest blue bells chiming a full peal, Saxifraga 
chrysantha like delicate fairy buttercups, and that tantalizing un- 
tamable beauty, Eritrichium argenteum. 
These grow in a coarse chip-rock of disintegrated granite con- 
taining varying amounts of peat. They hibernate under a_ thick 
blanket of snow, which as it melts provides an underflow of water 
at their toes. Thus the air and ground about them is always cool. 
The greatest success in growing alpines in hot regions at sea level 
has been achieved by providing as nearly as possible these conditions. 
PLAINS GROUP: 
Plants of the second group live under conditions totally different 
from those of the high mountains. The soil ranges from loose gravel 
to stiff clay or half decomposed shale, often alkali, sometimes neutral, 
rarely showing the slightest trace of acid, providing no such luxury 
as humus, for these plains are extremely dry except for occasional 
torreniial rains in spring and midsummer. Winter is sunny with 
dry winds. Zero temperatures without the protection of snow is the 
usual lot of these plants. Typical of this group are Melampodium 
cinereum, many of the Pentstemons, Townsendias, Yuccas, Galpinsia, 
and of course the hardy Cacti. 
Perhaps the only two conditions common to both groups are: 
(1) thorough drainage; (2) dry crowns after blooming. 
Directions and suggestions for growing new or little-known 
plants are rather futile. A condition moist for Colorado is usually 
dry for England; good garden soil may mean an infinity of things. 
Therefore a description of their habitat and its conditions will serve 
probably better than definite instructions. 
