378 



THE STUDY OF PLANT COMMUNITIES 



Hypodispersion, 64 

 Hypnum crista-castrensis, 23 



Ilex glabra, 257 



vomit oria, 259 

 Indifferents (fidelity), 72 

 Infiltration, 163 



on forested and bare land, 94 

 Influents (animals), 26 

 Inhibition of growth, 182-183 

 crop rotation, 182 

 decomposition products, 182 

 experimental evidence, 182 

 fairy rings, 182 

 seedlings, 182 

 toxic excretions, 182 

 Insolation, 116-118 

 exposure, 133 

 equinoxes, 116 

 greatest total, 117 

 heat, 116 



maximum effectiveness, 124 

 position of the earth, 117 

 seasonal, 116-117 

 solstices, 116-117 

 variations 



absorption, 116 

 angle of incidence, 116 

 daily, 116, 117 

 latitudinal, 116, 117 

 seasonal, 116-117 

 Interglacial plant remains, 302-303 

 Introduced species, 207-209, 318 

 effects of, 206, 207-208 

 Elodea, 206 

 gypsy moth, 207 

 mongoose, 208 

 muskrat, 206-207 

 prickly pear, 207 

 rabbits, 207 

 sparrows, starlings, 206 

 water hyacinth, 206-207 

 Irrigation, 353 



J 



Jatropha stimulosa, 257 



J uncus, 175 



Juniperus cembroides, 267 



monosperma, 267 



occidentalis, 267, 273 



pachyphloea, 267 



scopulorum, 267-268 



utahensis, 267 



K 



Kochia vestita, 286 

 Koeleria cristata, 292, 293, 295 

 Krummholz, 101, 102, 145, 263 

 Knees, of cypress, 176 



Lactuca scariola, leaf position, 137 

 Land management, 329-332, 333 

 Landscaping, 347-350 



ecological relations, 348 



natural, 347 



road building, 347, 348, 349, 350 



Land surveys 



reconstruction original vegetation, 

 53 

 Land use and ecology, 328-329 

 fish ponds, 329 



hedges and field margins, 329, 331 

 hillculture, 328 

 pasture, plowland, forest, 328 

 stream margins, 330 

 Larix laricina, 216, 241, 303 



occidentalis, 279 

 Lacunar tissue, 175 

 Larrea, 297 



tridentata, 288, 289 

 Laterite and laterization, 156 

 Leaching 



and soil acidity, 178 

 solubility of soil constituents, 145 

 Leaf arrangement, 136-137 

 Leaf exposure, 137 



profile position, 137 

 Leaf fall and photoperiod, 143 

 Leaf structure 



affected by water and aeration, 



138-139 

 in mesic habitats, 1 39 

 in sun and shade, 137-140 

 Ledum groenlandicum, 242 



palustre, 239 

 Lemaireocereus schottii, 288 

 Length of day, 141-143 

 and hardening 

 Abelia, 142 

 evergreens, 142 

 effects on plants, 141-143 

 Leptilon canadense, 51, 52, 221 

 Libocedrus decurre?is, 274 

 Lichens 



epiphvtes, 193 



in rock succession, 218, 219-220 



