FOREST BOTANY 159 



Pearson, G. A. (3135) 



the growing season of western yellow PINE. Jour. Agr. Research 29: 

 203-204. 1924. 



Pemberton, C. C. (3136) 



field studies of growth forms of some of the native trees of the environ- 

 ment of victoria, b. o. Canad. Field Nat. 39 (5) : 96-105; (6) : 131-137, 

 illus. 1925. 



Penhallow, D. P. (3137) 



the relation of annual rings of exogens to age. Canad. Rec Sci. 1 (2) : 

 162-175. 1885. 



Rigg, G. B. (3138) 



growth of trees in sphagnum. Bot. Gaz. 65 : 359-362. 1918. 



Stout, A. B. (3139) 



the intermittent annual growth of woody plants. Jour. N. T. Bot. Gard. 

 17 (201) : 147-152, illus. 1916. 



Trowbridge, C. C, and Weil, Mabel. (3140) 



the coefficient of expansion of living tree trunks. Science 48 : 348-350. 

 1918. 



Westveld, R. H. (3141) 



conifers vary in rapidity of growth. Mich. Agr. Expt. Sta. Quart. Bull. 

 13 : 57-58. 1930. 



LIGHT RELATIONS 



Adams, W. R., Jr. (3142) 



STUDIES IN TOLERANCE OF NEW ENGLAND FOREST TREES, 8 ! EFFECT OF SPACING IN 



A jack pine plantation. Vt. Agr. Expt. Sta. Bull. 282, 51 pp., illus. 

 1928. 



(3143) 



STUDIES IN TOLERANCE OF NEW ENGLAND FOREST TREES, 10 I THE CHANGE IN THE 

 ENVIRONMENTAL FACTORS CAUSED BY THINNINGS IN PINE PLANTATIONS. Vt. 



Agr. Expt. Sta. Bull. 310, 40 pp., illus. 1930. 

 Ashe, W. W. (3144) 



A POSSIBLE MEASURE OF LIGHT REQUIREMENT OF TREES. SOC Amer. Foresters 



Proc. 10: 199-200. 1915. 

 Bates, C. G. (3145) 



THE RELATIVE LIGHT REQUIREMENTS OF SOME CONIFEEOUS SEEDLINGS. Jour. 



Forestry 23 : 869-879, illus. 1925, 



(3146) 



THE ROLE OF LIGHT IN NATURAL AND ARTIFICIAL REFORESTATION. Jour. Forestry 



15: 233-239. 1917. 

 and Roeser, J., Jr. (3147) 



LIGHT INTENSITIES REQUIRED FOR GROWTH OF CONIFEROUS SEEDLINGS. Amer. 



Jour. Bot. 15 : 185-194, illus. 1928. 

 Burns, G. P. (3148) 



STUDIES IN TOLERANCE OF NEW ENGLAND FOREST TREES, III I DISCONTINUOUS 



light in forests. Vt. Agr. Expt. Sta. Bull. 193 (Vt. Forestry Pub. 20), 

 23 pp., illus. 1916. 



(3149) 



STUDIES IN TOLERANCE OF NEW ENGLAND FOREST TREES, TV: MINIMUM LIGHT 

 REQUIREMENT REFERRED TO A DEFINITE STANDARD. Vt. Agr. Expt. Sta. Bull. 



235, 32 pp., illus. 1923. 



(3150) 



STUDIES IN TOLERANCE OF NEW ENGLAND FOREST TREES, V : RELATION OF THE 

 MOISTURE CONTENT OF THE SOIL TO THE SENSITIVENESS OF THE CHLOROPLAST 



to light. Vt. Agr. Expt. Sta. Bull. 257, 16 pp., illus. 1926. 



(3151) 



STUDIES IN TOLERANCE OF NEW ENGLAND FOREST TREES, VII : LEAF EFFICIENCY 

 IN THRIFTY AND STUNTED WHITE PINE SEEDLINGS. Vt. Agr. Expt. Sta. Bull. 



267, 27 pp., illus. 1927. 



