346 XXIII. LEGUMINOSAE 



;ife again, sending up new shoots from dormant buds at the points marking 

 the axils of the cotyledons or from buds on the main stem if the latter has 

 not been completely killed. The second year's shoot is even smaller or more 

 weakly than that of the first year, the plant's energies being concentrated on 

 developing its root-system. On shallow soil the taproot does not develop 

 greatly in length, but thickens somewhat, and there is a marked diminution 

 in the number of lateral roots. Dying back occurs again at the end of the 

 second season. 



Third and subsequent seasons. In the third season a new shoot is produced 

 from the root-collum, neither larger nor more vigorous than that of the second 

 season. Meanwhile the taproot develops slowly in length and thickens con- 

 siderably. The annual dying back of the stem and gradual development of 

 the taproot continues year after year for an unknown period, which Mr. Witt 

 estimates at not less than ten years, the portion above ground gradually 

 developing into a many-branched bush 12-18 in. high. A marked change 

 then takes place : dying back ceases, and a leading shoot forms and grows 

 up at the rate of about 1 ft. or more annually. By this time the seedling 

 may be said to have reached the sapling stage, and the taproot has now 

 become much thickened, with a length up to about 8 ft., ^the length varying 

 with the depth of the soil : in shallow rocky soil the taproot is much twisted. 

 At the commencement of the sapling stage a natiu-al plant, especially in areas 

 subject to grazing, usually consists of a bushy and many-branched base, from 

 the centre of which rises the leading shoot. As the sapling increases in height 

 the bushy growth at its base gradually dies off, and by the time the plant 

 is 10 ft. high it has disappeared altogether. Each year's growth in the sapling 

 is marked by slightly raised annular marks. These are due to the fact, already 

 noted, that a portion of each year's shoot is shed at the end of each season ; 

 a scar is thus formed, on the surface of which develops a bud which produces 

 the following year's shoot. The annular marks represent the scars formed in 

 this way. 



The phenomenon of dying back on the part of natural seedlings has been 

 recorded by previous observers in other localities. Thus Mr. E. D. M. Hooper, 

 writing in 1903, mentions its habitual occurrence in the dry districts of Madras 

 where the tree grows, and attributes it partly to fire and partly to the excessive 

 heat of the dry season, and he mentions also the bushy form of growth which 

 this dying back produces until a definite leading shoot is formed.^ Mr. L. S. 

 Osmaston - estimates the period of dying back at four to seven years in West 

 Khandesh. 



The phenomenon of dying back, however, is not necessarily universal, 

 for under favourable conditions the seedling may shoot up without any check. 

 Thus Mr. Hooper observes that occasionally under favourable circumstances 

 a patch of young seedlings from its earliest life grows without hindrance, and 

 notes having seen a plant grown on prepared soil at Nagpur on a trap ridge 

 which in one season was over 5 ft. in height. Again, in patch sowings of 1911 

 in the Saugor district, Central Provinces, some of the seedlings are reported 

 to have reached a height of 3 ft. in three years. Nursery plants at Dehra 

 Dun, kept weeded and watered, reached a height of 6 to 14 in. by the end of 



1 Ind. Forester, xxxi (1905), p. 104. 2 75 /^^ xxxv (1909), p. 381. 



