Vol. IX. No. 211. 



THE AGRICULTUEAL NEWS. 



173 



STUDENTS' CORNER. 



JUNK. 



First rEEioD. 

 Seasonal Notes. 



Iti many cases, where the cane has beeh removed from 

 fields for the present crop, the undergnmnd system will be 

 allowed to remain in the soil, in order that ratoons may be 

 obtained in the next season Tillage of the ratoons is usually 

 effected. Discuss the i>ossible advantages and disadvantages 

 of such tillage, especially with reference t(j the .structure of 

 the underground system of the sugarcane. (See West Indian 

 Bulletin, \o\. X, pp. 117-21.) Why is trash often spread 

 over the surface of the soil in fields of ratoons? Where 

 the cane stumps are removed in order that the land may be 

 used for cotton or other crops, observe the condition of these 

 as regards insect pests, such as the root borer, and in relation 

 to fungus disease. 



The observations made in connexion with the reaping of 

 the cane will be continued until the end of the crop season, 

 and a large amount of useful information will be obtained by 

 conducting them in the mill yard, as the canes come in to be 

 ground. It is here that imlications a.s to the amount and 

 kinds of the diseases that are attacking the canes are obtained 

 most easily. In addition to this, the mill work will be 

 observed, especially with the object of gaining a knowledge 

 of the milling qualities of the different varieties of cane 

 grown on the estate. 



Why is cane juice treated with lime .' How is the proper 

 amount of lime for the pu'-jiose dutermineil .' In some cases, in 

 the muscovado process, it is the custom to add a certain pro- 

 portion of the lime to the liquor in the tayches. Why is this 

 practice objectionable, and what effect is it likely to produce, 

 in relation to the taste of the molasses made ] 



Before being crushed, all the cane coming into the sugar 

 works should be weighed, whether this is necessary on 

 account of the fact that some of it is being purchased from 

 growers, or not. In this way, nmch useful information in 

 connexion with the efficiency with which the several parts of 

 the proce.ssare being performed will be obtained, and a useful 

 fontrol on the working will be supplied, .•^o that the necessity 

 for making such changes as will improve the output of sugar 

 will be recognized. In the absence of regular weighing, 

 much unsuspected loss will occur, and its adoption as 

 a matter of routine will well justify any extra expense that 

 may be incurred. 



AVhen the yams that have been allowed to remain in the 

 fields have been dug, note should be made of the difference 

 between the.se and the ones which were harvested at maturity, 

 and stored. In planting yams, the sets (cutting.s) should be 

 passed through Bordeaux mixture: they will then germinate 

 better, and are less likely to be attacked by insect and fungus 

 pests. AVhere sets of different sizes are u.sed for [)lanting, the 

 growth of the plants springing from the larger ones should be 

 compared with that of the sprouts from those which are 

 smaller. If pen manure is applied to the soil on which the 

 yams are grown, a useful experiment is afforded by mixing 

 the manure with the soil in one part of the area and apply- 

 ing it around the yams in the other, and noting the 

 difference in yield from the two areas when they are reaped. 



Note that the cotton that is picked latest in the season 

 contains more stained lint than that which was produced 



earlier. Make observations to find out if all cotton staining 

 IS due to the cotton stainer, or if there are other causes of it. 

 Lxanune carefully the lint as it comes from the gin, noticing 

 the nature of the chief foreign substances that are mixed with 

 It: consider if any greater care in picking would make such 

 cotton cleaner. What is the true nature of the small, green 

 bodies that are generally found entangled in cotton lint' If 

 possible, examine the seed from plants fhat have been grown 

 where .seed selection has been carried out regularly, and that 

 from plants produced where seed selection^is not practised. 

 iNotiee the variability of the latter seed, especially as regards 

 size and the amount of fuzz on the individual seeds. 



Questions for Candidates. 



PEEHJII.\.\EY QUESTIONS. 



(1) What is the difference between light and heavy 

 .soils; How may heavy .soils be made lighter! 



(2) Why is the mould-board of a plough curved, and 

 what IS the effect of curves of different extent* 



(.3) How would you select seed for corn-planting? 



INTEEMEDI.\TE QUE.STIONS. 



(1) Describe the different ways in which sweet potatos 

 are propagated. Does any of these methods afford special 

 advantages? 



(2) Give an account of as many methods as you can, 

 for propagating the mango. 



(3) How would you make a nursery for (a) sugar-cane 

 seedlings, (b) cacao, (c) limes? 



DESTRUCTION OF THE PRICKLY PEAR. 



The Cape of Good Hope Department of Agriculture 

 publishes, in the A<iri<'ultur<il Journal of the. Cape of Good 

 Hope, for March 1910, particulars concerning a niixture, 

 known as Jansen's extirpator, which is successful in effect- 

 ing the destruction of the prickly pear. It is made as 

 follow^s: (1) l-tt). good, finely powdered lime and i-lb. sulphur 

 are boiled for half an hour in 1 gallon of wat«r, 1 quart 

 of water being added to make up for evaporation: (2) i-lb. 

 .salt and i-lb. arsenite of soda are dissolved in 1 gallon of 

 boiling water: (3) the portions of liquid thus obtained are 

 mixed together to form the preparation. 



The way in which the mixture is used is to make an 

 incision, with a sharp knife, in one or more of the fiat parts 

 of the plant, according to its .size: the cuts should be 2 or 

 3 inches deep. Where there are no branches, one incision, 

 only, is required— at the top of the plant. The cut is made 

 on the upper side of a fiat portion of the stem, the knife 

 being moved to and fro in order to enlarge it. It is then 

 opened by giving the knife a half twist, and a small stone is 

 placed in the incision in order to keep it open. The prepara- 

 tion is stirred well, and a little of it is poured into the 

 wo ind from a suitable vessel. The poison travels through 

 the plant, finally killing it. 



Where the prickly pear grows in dense patches, it is 

 necessary to effect its destruction in several stages. This is 

 done by treating the plants on the outside of the patch, and 

 then, when these are dead, applying the preparation to those 

 which were growing next to them, and so on. 



Spraying the mixture is of no avail. It is not known 

 yet if the treated plants are poisonous, so that caution should 

 be exercised where they are likely to be eaten by stock. 



