34 VAGABOND SPECIES [CH. 
p- 28), and need not be further specified. In gaps, 
borders, and copses—half-shade—we find several common 
grasses—e.g. 
Anthoxanthum odoratum. Triodia decumbens. 
Agrostis alba. Dactylis glomerata. 
Aira flexuosa. Festuca rubra. 
ffoleus lanatus. Brachypodium pinnatum. 
Arrhenatherum avenaceum. Hordeum sylvaticum. 
Whereas 
Poa nemoralis, Milium, 
Festuca sylvatica, Bromus asper, 
Agropyrum caninum, B. giganteus, 
Melica, Brachypodium sylvaticum, 
are more likely to be met with in the deep shade inside 
the forest. 
On the other hand there are vagabond grasses which 
seem to show no signs of preference for one soil over 
another—e.g. Poa annuwa—though in some cases these 
ruderal plants indicate the presence of rotting substances, 
on ash-heaps and rubbish of various kinds. 
With reference to the above, however, the student 
must not forget that very complex relations are concerned 
in changes of soil, shade, moisture, elevation, &c. and that 
although experienced observers can draw conclusions of 
some value from the presence of nwmerous species and 
indwiduals on a given soil, no one must conclude too 
readily that a soil is so and so, from observing solely that 
a particular kind of grass will grow there. 
An excellent example of what may be done by applying 
such knowledge as exists of the habits of grasses, is 
afforded by the historic case of the planting up of shifting 
