394 



XXIII. LEGUMINOSAE 



drought ; such plants, if they survive, are apt to assume for a time a bushy 

 form owing to the development of new shoots from the lower portion of the 

 stem. In the natural home of the tree, rats are often very destructive to young 

 plants, gnawing them just below the ground-level ; in seasons of low inunda- 

 tion, when the rats become numerous, their ravages are worst. The leaves 

 of seedlings fall dm"ing the cold season, the young plants being leafless for 

 a time towards the end of that season. 



The following measurements of seedlings grown in experimental plots at 

 Dehra Dun (which, however, is outside the natural habitat of the tree) compare 

 to some extent the growth under varying treatment : 



Growth of Prosopis spicigera seedlings under varying treatment, Dehra Dun. 



O 



< 



Condition under 

 which grown. 



(1) In nursery, weed- 

 ed and watered 



(2) In nursery, weed- 

 ed and watered 



(3) Broadcast sowing, 

 irrigated, weeded 



(4) Broadcast sowing, 

 irrigated, unweeded 



Height at end of season. 



1st season. 2nd season. 3rd season. 



ft. I in.-0 ft. 3 in. Maximum ft. 5 in. ft. 3 in.-O ft. 8 in. 



(side branches up 

 to 1 ft. 7 in. long) 



(5) Broadcast sowing, 

 imirrigated, weeded 



Maximum 1 ft. 2 in. 

 (with several strag- 

 gling branches) 



ft. 3 in.-l ft. 9 in. 



1 ft. 1 in.-l ft. 4 in. 

 (only a few sur- 

 vived the weeds, 

 but now over them 

 and in good condi- 

 tion) 



Maximum ft. 4 in. Maximum 1 ft. in. 



Maximum ft. 6 in. 



Maximum ft. 8 in. 

 (vigorous and 

 numerous) 



Maximum ft. 5 in. 

 (few, weakly) 



ft. 2 in.-0 ft. 9 in. 

 (decrease due to 

 damage by frost and 

 drought). 



(6) Broadcast sowing. Maximum ft. 7 in. ft. 2 in.-l ft. 4 in. 

 unirrigated, weeded (seedlings numerous) (seedlings numerous) 



(7) Broadcast sowing, 

 unirrigated, un- 

 weeded 



Maximum ft. 7 in. 

 (seedlings few) 



(all killed by frost 

 or suppression) 



SiLvicuLTURAL CHARACTERS. The tree is a decided light-demander. 

 Although the seedlings are sensitive to frost and drought, older plants are 

 very drought-resistant and stand frost better than Acacia arahica. Although 

 it resists ordinary frosts within its habitat, it suffered somewhat in the Punjab 

 plains during the abnormal frost of 1905. A most important characteristic 

 of the tree is the extremely long taproot which it develops ; this enables it to 

 retain possession of the ground, in the dry regions which it inhabits, by obtain- 

 ing its water-supply deep down in the subsoil. Gamble ^ mentions a specimen 

 of a taproot, exhibited at Paris in 1878, which was 86 ft. in length, and had 

 penetrated vertically for 64 ft. Mr. Navani '^ mentions a taproot which was 

 dug up in Sind and found to measure 117 ft. in length. 



1 Man. Ind. Timbers, 1902, p. 288. 



2 Revised Working Plan for the Jerruck Forest Division, Sind, 1915. 



