Ammoniac, M ana-grass, &c. 261 



but of little use as manure, but when put in with 

 cow-dung, as previously described, or with other 

 substances by which their decomposition is pro- 

 moted, they become valuable. In any case, how- 

 ever, even if it will do no more, digging in grass of 

 this nature will greatly improve stiff, clayey soils, 

 by rendering them loose and friable. In wet, ex- 

 posed situations, with cold, stiff soils, it is an 

 excellent plan to cover the ground under the coffee 

 trees with a stratum of mana grass ; the ground by 

 this means is kept warm, throws off excessive 

 rainfall, while weeds are kept down and wash 

 entirely prevented. Mr. Wall writes on this plan : 

 "I have applied it to a cold, heavy, yellow soil, in 

 which coffee bushes could scarcely exist, and where 

 their scraggy branches had only a few small, yellow 

 leaves upon them, and the effect was most sur- 

 prising. Not only were the trees soon clothed 

 with fine dark-green foliage, but even the soil 

 appeared to be changed, and to the depth of three 

 or four inches became friable and dry." 



This "ground-thatching" may be tried with 

 equal prospect of benefit in hot, dry situations, to 

 enable the ground to retain its moisture ; but 

 great care must be taken to guard against fire, 

 especially in the neighbourhood of grass hills or 

 jungle likely to be burned in the dry season. A 

 spark falling on this ground-thatch might set a 



