586 



Insect and Fungus Pests in Septembek. 



[Sept., 



creosote emulsion, may be used. The presence of this tiny 

 white fly can usually be detected readily by shaking the tree or 

 branch. Further particulars are given in Leaflet No. 16. 



Fruit growers should make preparations for grease banding 

 their trees, and obtain the necessary materials. The reason for 

 grease banding trees is that certain moths, chiefly the Winter 

 Moth, the Mottled Umber, and the March Moths, have wingless 

 females which have to climb the various trees before they can 

 lay their eggs. Full particulars of these moths are given in 

 Leaflet No. 4. The moths first appear above the ground about 

 the end of September, and may appear any time during the 

 next few months, according to soil and other conditions. If 

 the grease on the bands is kept sticky the moths are caught 

 and prevented from laying their eggs on the tips of the shoots. 

 Every moth caught would probably lay several hundred eggs, 

 which in due course would hatch out to the familiar green 

 caterpillars which cause so much damage early in the year. 

 Such bands are of no value in checking the Codlin Moth, but 

 the hay bands recommended for this in a previous article (July, 

 19*20, p. 378) should now be removed and burnt. 



Cereals. — All cereals should be harvested by September, but 

 it may be mentioned here that the Gout Fly or the Ribbon-footed 

 Corn- fly, as it is also called, caused much damage this season 

 to wheat and barley. The latest brood will lay its eggs on 

 wild grasses, or on young wheat if this is near. In such cases 

 wheat and barley should not be sown close to a previously 

 infected field. The grass on the headlands should be kept down, 

 and if wheat has to be sown near, the operation should be 

 deferred as late as possible, so that the late brood of flies may 

 find no young plants on which to lay their eggs. 



General. — It cannot be too strongly urged that the collecting 

 and burning of refuse in gardens and fields is the best possible 

 preventive of further damage by different pests, since a great 

 many of the common pests over-winter in the refuse heap and 

 frequently find their way back on the land when the manure is 

 distributed in the spring. 



For the same reason infected food plants should not be given 

 raw to animals, as in many cases the fungus spores pass 

 unchanged through the animals and are replaced often on 

 uninfected land with the dung. Many fields are infected with 

 injurious soil-inhabitating fungi in this way. 



Any of the Leaflets mentioned in this article may be obtained gratis and post free 

 on application to the General Secretary, Ministry of Agriculture and Fisheries. 



