ACACIA * 453 



damping off to which they are subject during the rains : in tall open grass, 

 however, where they are not subjected to such a degree of damp, they are 

 capable of making their way up successfully, though their development is 

 comparatively slow during the process. 



The effect of light on the development of the seedling has been studied 

 at Dehra Dun in the case of plants grown in plots under varying degrees of 

 shade : these tests proved the seedlings to be strongly light-demanding, and 

 liable to be killed out in one season where the shade is at all dense. The 

 seedlings are frost-tender during the first few years, and are also apt to suffer 

 from drought during long periods of dry weather. In dry regions they some- 

 times die back for a few years in succession, eventually shooting up after the 

 root has established itself. Rats do much injury to the seedlings by gnawing 

 through the taproots. The power of recovery of the plants, however, is good, 

 numerous cases having been observed of new shoots being sent up from the 

 portions of the taproots left in the ground after this form of damage. Similar 

 new shoots were found to be sent up from the roots in the case of plants 

 thinned out in unirrigated line sowings at Dehra Dun, in which the taproots 

 were severed a few inches below ground-level. Young plants are very subject 

 to browsing by deer. 



SiLVicuLTURAL CHARACTERS. Acacta Catechu is a strong light-demander. 

 Within its habitat it is decidedly frost-hardy, though young seedlings are 

 somewhat tender : in the abnormal frost of 1905 in northern India it stood 

 the frost better than most species, though young coppice growth was killed 

 back. It is often found thriving in frosty grass-lands where tender species 

 succumb. Although decidedly xerophilous in character, and capable of growing 

 in dry situations where almost every other species fails to survive, it may 

 suffer severely in years of abnormal drought, as in 1899-1900 and subsequently 

 in the Indian Peninsula, and in 1914-15 in Palamau, Chota Nagpur. In the 

 abnormal drought of 1907 and 1908 in Oudh it was unaffected on the low 

 alluvial lands where it grows. 



The tree coppices well up to a moderate size and produces root-suckers, 

 particularly where the roots have been exposed : coppice-shoots, however, 

 require complete light for their development, and under shade they are 

 frequently not produced at all, the stools dying off. It is very subject to 

 damage by browsing, and responds readily to closure to grazing. Porcupines 

 are particularly destructive to the trees, gnawing the bark off round their 

 bases and often killing them. Ranger Basti Ram ^ reports that he has found 

 a smearing of lime efficacious in keeping them off. An American plan for 

 dealing with porcupines is to soak small boards in brine and strychnine and 

 nail them to the bases of the trees ; the porcupines have a partiality for salt 

 and gnaw the boards, dying of strychnine poisoning. 



In the mixed forests Acacia Catechu is subject to the usual damage from 

 climbers. In the sub-Himalayan alluvial forests a very characteristic climber 

 is Dregea volubilis, which does great damage ; other common climbers in these 

 forests are Cryptolepis BucJianafii and Vallaris Heynei. 



Natural reproduction. Under natural conditions the seed is dis- 

 seminated by wind, the seeds adhering to the light pod-valves ; in alluvial 



1 Ind. Forester, xli (1915), p. 383. 



