460 The Philippine Journal of Science wu 



ing in the area covered by Homalanthus populneus, and so it 

 would seem that Hoynalanthus, if not destroyed by boho, would 

 make a good nurse crop for Pentacme. Other species also may 

 be able to survive under Homalanthus, but this point has not 

 been determined. The success of Pentacme is probably con- 

 nected with the moist conditions at the high altitude at which 

 the logging is now being done. 



CLEARED LAND AT THE BASE OP MOUNT MAQUILING 



The two cases of second growth which we have described 

 occurred on cleared land which had not been cultivated. The 

 area to be considered now has been in grass as the result of 

 cultivation. All of the land around the base of Mount Maquiling 

 has been cleared of the original forest and put under cultivation. 

 Much of it has subsequently grown up in grass, and cultivation 

 has been abandoned. The College of Agriculture was established 

 in 1909 on such an area on the northeastern side of the mountain. 

 Between the college buildings and the mountain there were ex- 

 tensive grass areas. The region under consideration consists 

 of broad flat ridges about 75 meters in altitude and separated 

 by narrow valleys. The original forest remained, but in a very 

 badly cut-over condition, in the valley of Molauin River. 



Before the establishment of the college most of the area ap- 

 pears to have been burned over very frequently, and large 

 portions of it were burned as late as 1911. Since then fires 

 have been largely excluded, and the area is rapidly going over 

 into second-growth forest. 



As long as any area continued to be burned over, tree seedlings 

 were killed and the area remained in grass. The grass consisted 

 mostly of two species, Imperata exaltata (cogon) and Saccharum 

 spontaneum (talahib). Imperata appears to be disseminated 

 quicker than Saccharum, and at first probably occupied the 

 larger part of the area. At present it occupies all of the driest 

 spots, but is apparently giving way to Saccharum in the more 

 favorable localities. Table XIII gives a good idea of the average 

 composition of an area dominated by Imperata. 



Table XIII shows that there are many herbs and shrubs pre- 

 sent with Imperata, but that they are all small plants. With the 

 exception of Eulophia, which has large underground roots, all of 

 the plants have come in since the last fire and have not had time 

 to reach their normal size. The vines are likewise recent ar- 

 rivals. The presence of the large number of small miscellaneous 

 plants shows clearly that if fire is excluded from the area, plants 

 other than Imperata will become prominent very quickly. 



