782 XLVI. VERBENACEAE 



to be carried out with great caution owing to the danger of the insect spreading 

 to other host plants of valuable species. 



Although the lantana is a serious pest under many conditions, it is not 

 always to be regarded as devoid of good qualities of any kind. Outside forest 

 tracts the principal charges against it are that unless kept in check, often at 

 considerable cost, it quickly overruns and monopolizes waste lands, grazing- 

 grounds, cultivated land left fallow for a short time, and coffee and other 

 plantations, and owing to the high cost of eradicating it it is a serious check 

 to the spread of cultivation ; in the neighbourhood of cultivated or village 

 lands it harbours pigs, which destroy the cultivators' crops, and dangerous 

 carnivora, which devour his cattle ; round stations, cantonments, and villages 

 it creates insanitary conditions. 



Within the forest its effects vary to some extent with the class of forest 

 concerned. In deciduous forests if fire enters a lantana-infested tract, which 

 it is almost certain to do periodically, the conflagration is so intense that trees 

 of all sizes may be killed outright, and immense damage to the crop may 

 result. It is quite impossible to extinguish a fire raging through a thick growth 

 of lantana, and two or three years after a severe fire the weed is as dense and 

 luxuriant as ever, and profits by the opening of the overhead canopy. Again, 

 natural reproduction of the light-demanding species, which are often the most 

 valuable species, is effectually checked. Even sandal seedlings cannot survive 

 long under a really dense crop of lantana. Still, when the lantana is removed 

 in the manner described above, natural reproduction of tree species comes 

 up plentifully on the cleared areas ; lantana undoubtedly enriches the soil, 

 and forms a clean germinating bed very favourable to natural reproduction 

 when light is admitted. Mr. Tireman, in his paper already referred to, gives 

 instances of profuse reproduction of Anogeissus latifolia on lantana areas 

 from which the weed has been cleared after repeated burning, while teak, 

 Dalbergia latifolia, Pterocarpus Marsupium, and other valuable species also 

 regenerate freely on such areas. 



Although fires are not so liable to occur in the evergreen as in the deciduous 

 forests of southern India, they do sometimes take place in the former in dry 

 years, and the damage done may be considerable owing to the susceptibihty 

 of the evergreen species to injury ; in the event of fire an undergrowd:h of 

 lantana may therefore prove to be a serious menace. On the other hand, 

 although lantana persists in evergreen forest, it does not become luxuriant 

 when the canopy is dense and may in time be killed out, while seedlings of the 

 shade -bearing evergreen species are better able to establish themselves under 

 its cover than those of the more light-demanding deciduous species. Thus 

 except for the danger of fire, which is not always present, lantana in ever- 

 green forests is not, as a rule, the serious pest which it may become in deciduous 

 forests. 



Although a serious scourge under many conditions, there are cases where 

 the effects of lantana are beneficial to the forest. Owing to its soil-improving 

 capacity it is a useful plant on poor shallow rocky soil. Where not too dense 

 it may serve as a useful nurse to valuable species, and instances have been 

 noted where it has been of considerable help in the establishment of sandal 

 reproduction ; it is sometimes held that lantana is connected with the spike. 



