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and nearly all the underground stem had been destroyed, were washed and trimmed, 

 and then planted and watered, and the earth kept well hoed up round them. Every 

 one of these grew and produced a head. In years of only light attack it is not at all 

 uncommon to find, when cabbages are pulled up, that they had been supported by 

 roots which were produced some distance above the original root-mass, which had 

 been destroyed early in the season by the cabbage maggot. 



Frequent cultivation or light hoeing is of great benefit to cabbages in dry 

 weather. By this means the thin layer of surface soil is loosened, aerated and thor- 

 oughly dried, so as to become a non-conducting medium, which prevents the evapora- 

 tion of moisture from the soil below. Hoeing the soil well up to the stems of cab- 

 bages which have been injured gives them a chance to make fresh roots, and also pre- 

 vents the flies from getting at the stems to lay fresh eggs. 



In the third week of July, I visited the garden of Mr. S. A. Fisher, M.P., at 

 Brome, P.Q., and was shown by his gardener, Mr. Louis G-raindorge, a bed of cabbages 

 which was in some parts badly infested with the Cabbage Maggot, I suggested that 

 he should try the Hellebore application, and the whole bed was treated. One parti- 

 cular plant was taken as a test and marked. This was so badly injured that the root 

 was almost severed from the head by the attacks of the maggots on the underground 

 stem. There were more than a dozen of the larvae lying close to the stem in the 

 earth, which was quite wet from the juices of the cabbage. The earth was carefully 

 removed sufficiently to pour in the decoction around the injured stem and then was 

 replaced, the larvae being disturbed as little as possible and left where they were at 

 thereof. In the end of September Mr, Graindorge writes me : " All the cabbage plants 

 are doing well. Tour test plant, the one which was nearly dead when you treated it 

 now weighs about three pounds. I am very much satisfied with this experiment, and 

 shall certainly try it another year and begin earlier in the season, when I believe I 

 shall be able to save all my plants. " 



In the above mentioned experiment it would appear that the Hellebore killed 

 by contact, for where a dozen cabbages were treated with Paris G-reen and water, 1 lb. 

 to 100 gallons, not only did it fail by noticeably checking the growth of the cabbage, 

 but the maggots were not killed. In applying this hellebore remedy, care must be taken 

 not to dig down too deep or disturb the root too much. The chief seat of injury is the 

 underground portion of the stem above the mass of roots. If about two inches of the 

 soil be removed that part of the stem most attacked is laid bare, but the roots need 

 not be disturbed. An important thing is not to put off treatment too long. In this 

 district injury is made manifest in the first week of July, examination should there- 

 fore be made, and the remedy, if necessary, applied about the third week in June. 



Late planting has been rather extensively practiced by some growers, but is not 

 always a satisfactory remedy. With early cabbage the most paying market is over 

 before they are ready, and with winter varieties there is the risk of their not heading 

 well before winter sets in. The actual success of the practice however as a preventive 

 of attack is sometimes most marked. 



The greatest amount of injury is caused by a brood of flies which appears in the 

 middle of June and up to about the first week of July. Cabbages planted out in the 

 middle of July were not at all troubled by the Maggot. This was in low moist 

 ground where the plants did not suffer from drought. They were kept well 

 cultivated and produced a large crop of fine cabbage. 



It is not, of course, wise to grow cabbage upon land where there has been an 

 infested crop the previous year. The usual method of hibernation is in the puparium 

 form ; but the attack continues throughout the whole growing season, and where, as 

 is frequently the case, the ground is not cleared up in the autumn and stems of 

 cabbages that have been cut, or "blind" plants which have not headed, are left in 

 the fields all the winter, manj^ larvae hibernate as such, in the stems and roots. 

 This shows the importance of cleaning up and ploughing the fields in autumn. 

 In this way many larvae and pupae will be destroyed, both by exposure to the 

 weather under unnatural conditions and in other cases by being buried so deeply 

 that the flies cannot emerge. 



6c— 11^ 



