72 PLANT HABITS AND HABITATS IN THE 



such dead specimens had certain points of interest. It was found 

 that soil no longer remained around the base of the halophyte when 

 dead as it does around the hving plant, but it is removed from the 

 root-crown, exposing the origins of the superficial roots very completely. 

 In every instance the dead root-crown is surrounded by a radiating 

 circle of small roots which start away in a fairly horizontal direction. 

 In one plant of undetermined species, where the superficial roots 

 were exposed in the manner indicated, 23 were counted, all very close 

 to the surface, but 3 or 4 were found more deeply placed. 



Living plants mostly were studied and the results, as above sug- 

 gested, were very uniform. A Kochia which was growing on the plain 

 at some distance from any wash was carefully removed from the ground. 

 A tap-root which penetrated 39 cm. into the soil was seen to be fairly 

 moist. All of the laterals, of which there were several, arose at a depth 

 of about 10 cm. from the surface and were traced more than 60 cm. 

 from their place of origin. A species of Atriplex, situated by the side 

 of a small wash and not far from the Kochia just mentioned, was 

 found to have a prominent tap-root and prominent laterals which ran 

 in a fairly horizontal direction, and not far beneath the surface. A 

 species of Salicornia, growing close by, had a root which penetrated 

 to a depth of 15 cm. and then, turning sharply, ran horizontally. Sev- 

 eral large horizontal roots arose within 10 cm. of the surface of the 

 ground and many small laterals took their origin at about half that 

 depth. So far as this species is concerned, therefore, the laterals 

 constitute a very prominent feature of the root-system as a whole. 

 That a recent rain of 0.21 inch penetrated to the roots of this species 

 was evident from the fact that the branches and leaves were turgid. 



Of the root exposures, however, the best were found along a recent 

 wash to the north of Table Mountain, where a small box canyon, 

 about 100 meters in length by half that width, had been eroded. 

 The sides were vertical and the walls about 1.2 meters high. The wash 

 ran through a small plain on which were Atriplex and Kochia mainly, 

 with Atriplex sp. dominant. The roots of several plants were partly 

 exposed and were observed. Since the roots of all were about the 

 same, a description of those of one will be sufficient. In this specimen 

 the shoot was only in part hving and it was apparent that a portion 

 had been removed. Of the roots, it was found that 3 fairly large ones, 

 representing tap-roots, went straight down over 1 meter. Several took 

 their origin from these vertical roots just beneath the surface of the 

 soil and ran in a horizontal direction, about 2 cm. beneath the surface, 

 to the base of a neighboring Atriplex, about 1.5 meter distant. The 

 vertical roots gave off small and relatively unimportant branches at a 

 depth of about 30 cm. The superficial horizontal roots bore numerous 

 filamentous roots and such roots were seen on the most superficial of the 

 other laterals. Such filamentous roots correspond to the "deciduous" 



