REED: MEADOW VEGETATION IN NORTHERN COLORADO 99 
and that the soil moisture shows 4.6—9.1 per cent (see Ramaley, 
etc., I, 2, 3). 
SEASONAL ASPECTS 
This study was carried on in 1915 and 1916 during two sessions 
of the University of Colorado Mountain Laboratory, extending 
from the last week in June to the first week in August. This 
embraces the summer season only, hence the spring and autumn 
aspects will be omitted. 
Early summer is characterized by a profusion of flowers; 
grasses and sedges also are to be seen but they are not yet in 
bloom. ‘The most conspicuous plants are Thermopsis divaricarpa, 
Pseudocymopterus tenutfolius, Castilleia sulphurea, and Pedicularis 
Parryi. The green of the foliage and yellow of the blossoms give 
the meadows at this time a yellowish green hue. 
Late summer has a great profusion of flowering dicotyledons 
interspersed with grasses. The conspicuous plants in flower are 
Campanula petiolata, Delphinium robustum, and three species of 
Potentilla. ‘These give the meadows either a bluish green or a 
yellowish green hue, depending upon whether the Campanula and 
Delphinium or the species of Potentilla predominate. 
SOCIETIES 
Owing to the varying conditions of moisture, differences in 
soil texture, and depth to subsoil, various societies may be dis- 
tinguished. The genetic relationship of the several societies has 
not been studied. The following seem fairly well marked and 
with each a few species of the mast prominent plants are given: 
1. Pedicularis-Pseudocymopterus Society.—In certain of the 
drier portions of the meadows. JPedicularis Parryi, Pseudocy- 
mopterus tenuifolius, Tium alpinum, Sieversia ciliata, Potentilla 
pulcherrima, Carex festiva, Festuca ingrata, Phleum alpinum. 
2. Thermopsis-Castilleia-Campanula Society.—Characteristic of 
drier portions of hillside meadows. Thermopsis divaricarpa, 
Castilleia sulphurea, Campanula petiolata, Bistorta bistortoides, 
Helianthella quinquenervis, Calochortus Gunnisonii, Allium Geyeri, 
Valeriana furfurascens, Festuca confinis, Phleum pratense, Stipa 
Nelsonii, Bromus Porteri, Danthonia Parryi. This society has 
* 
