143 



stumps that are left on the field are more or less liable to take 

 the Thielaz'iopsis rot, and for this reason it is very desirable to 

 remove these stum])s rather than let them rot on the field. If 

 they rot on the field they are pretty sure to become a factor in 

 the generation of some disease of the future crop. So long- as 

 pineapples are to follow^ pineapples, the greatest care should 

 be exercised to keep the fields clear of rotting or decaying parts 

 of pineapple plants, ivhcther fruit, leaves or roots. 



The industry is expanding rapidly in Hawaii, and in conse- 

 quence tops are worth two or three cents each. All tops that will 

 grow are being used, to a large extent, regardless of whether thev 

 are diseased or not. If the top fails it is replaced by another. 

 This at first may seem to be an economical operation, as it 

 gives the poor top a chance to show what it can do. If it 

 fails, another can be put in. But the gronnd at the place of this 

 failure becoines infested, hence the practice is a bad one, taking 

 the future into consideration. 



The old stumps are for the most part being plowed in. 

 This is a bad practice where pineapples are to be followed by 

 pineapples. Elxamination of the old stumps shows that they 

 are infested with fungi, among which is Thiclaviopsis, and when 

 this is the case this disease is being encouraged by allow- 

 ing the stumps to remain. There seems to be some little at- 

 tempt to burn the trash, but too little. All pineapple trash !s 

 inimical to subsequent pineapple crops. 



Where the water stands about a plant in the early stage, before 

 it has established itself, the plant suffers and often dies. This 

 is due to disease, often Thiclaviopsis, entering at the base and 

 getting ahead of the roots of the plant. Proper drainage will 

 remedy this local dying oil' of 3'oung plants. 



On some low lands the plants become yellow and die ofif, or, 

 at least, do not do well. This is a separate malady. The soil 

 at Wahiawa, Oahu, is said to lack lime. If this is so, liming 

 should be tried, especially at the low and poor patches. 



Plants occasionally die from the attacks of one or more 

 fungi on the leaves. For a long* time in advance of the actual 

 appearance of fungus fructifications these diseased leaves 

 may be picked out by their different color. The attack begins 

 at the tip of the leaves and works back. In any event, sooner 

 or later, these fungi attack the leaves, and it is probable that 

 a closer study of some of them might disclose facts of im- 

 portance in reducing losses. I have made a number of notes 

 regarding some of these fungus species which may be worth}^ 

 of publication at some future time. 



It is evident that at Wahiawa the common ripe rot of the 

 pineapple is Thiclaviopsis cthaccticus. 



