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be recognised by their abnormal shape and usually by their dull brown 

 colour. Those which retain their natural colour always lack the glossy 

 appearance of normal seeds. The extent of injury is not generally 

 apparent and in order to obtain an estimate of the percentage des- 

 troyed it is necessary to open a large number of the pods and to count 

 the infested seeds. Observations show that the early emergmg adults 

 crowd to the first seed-pods in large numbers, resulting in a heavy 

 infestation. These first pods are, however, nearly always found on 

 the isolated plants growing on fence lines and ditch banks. In 

 localities where bur clover is abundant, the pods of these plants receive 

 the early infestation. When the lucerne pods develop in large numbers 

 on the early seed fields there is apparently a decrease in the percentage 

 of infested seed, and from this time on a gradually increased infestation 

 follows until the close of the season. The pest destroys from 10 to 30 

 per cent, of the seeds in the early crops and from 20 to 70 per cent, in 

 the late ones. In the autumn of 1912, an investigation was started 

 with a view to determining some practical method of checking this pest, 

 and though much of the work is still in an experimental stage, certain 

 practices are available whereby the numbers may be reduced in 

 the lucerne fields. In the case of a very severely infested field, 

 the custom of driving in cattle to pasture is a great mistake, as many 

 of the pods are burst open, while others are trampled to the ground, 

 producing conditions favourable to the hibernation of the larvae from 

 which adults will emerge and infest the seed crop in the following 

 spring. The crop should be mowed, removed from the field, and 

 stacked. It may then be used as rough fodder, and if the remaining 

 straw is burned in early spring, the hibernating larvae will be destroyed. 

 It is most important that the lucerne along ditch banks and fence lines 

 should be cut and this should be done with the harvesting of each hay 

 crop, before the seed crop is grown. Where land is enclosed between 

 two parallel ditches, it is economical to fence them and use the land 

 as a summer pasture, thus preventing the growth of the pods and the 

 development of their parasites. In harvesting the seed crop, many 

 infested pods drop to the ground and a thorough cultivation wuth a 

 lucerne cultivator, either late in autumn or early in winter, will cover 

 such pods sufficiently to prevent the emergence of the adults when 

 the warm spring weather arrives. After the lucerne is threshed, the 

 chaff and the screenings should be placed in a compost pile for three 

 or four months so that it may become heated and decayed, most of 

 the insect life being destroyed. Unless this treatment is carried out, 

 the screenings should be burned before the growing season opens in 

 spring. In the autumn or early spring many pods along check ridges 

 and fence lines may be destroyed by burning off the weeds and lucerne. 

 Only seed that has been well cleaned after threshing should be planted ; 

 the uncleaned product should never be planted in new fields, as it not 

 only gives poor results, but also gives the pest a start. The seed crop 

 should be so handled that the setting of the pods will be as uniform 

 as possible, and the crop should then be harvested as soon as the larger 

 number of pods are ripe. Where the crop is allowed to remain on the 

 field for a lengthy period in order that all the green pods may develop, 

 ripe, half-grown, and newly formed pods occur together on the same 

 plant. Many individuals infesting the earlier pods thus hav3 time to 

 complete their development and after emerging, deposit their eggs 



