82 CORN AND GRASS. [1899 



Applications that have been found to answer as a dressing, or in 

 bringing crops through bad attack are, — guano ; guano and salt mixed 

 at the rate of 4 cwt. per acre; also guano 1^ cwt., salt 2 cwt., kainite 

 and superphosphate each 1 cwt. per acre. 



Nitrate of soda acts ivell, as being a rapid fertilizer, and also ob- 

 noxious to the grub ; and has been reported as having thoroughly 

 good results, given at the rate of 1 cwt. the acre, to Barley when just 

 above ground, on badly grub-infested land. A mixture of nitrate of 

 soda and salt has proved useful, applied at the rate of rather more 

 than 3 cwt. of salt and rather less thau 1 cwt. of nitrate per acre, after 

 rolling with a Cambridge roller, and harrowing. But in whatever way 

 applied, nitrate of soda, or any other good fertilizer which will act at 

 once, if melted and driven down by rain, has been found to have a 

 good effect, unless (see p. 31) the rainfall is so great as to wash the 

 fertilizer away. 



Salt alone, applied as a remedial dressinr/ where the grub tvas present, 

 has failed in many cases to do good. In special experiments it has 

 been found that, applied at a rate which killed the plants, salt had no 

 effect on the grubs, except to drive them down for a time to a depth 

 beyond its influence. But as a preventive dressing to ley-land before 

 ploughing up, it has been found highly serviceable. Salt at the rate 

 of from 5 to 12 cwt. applied before breaking up, or lime and salt mixed, 

 would probably do much good. A heavy dressing of salt which would 

 kill Grass, Couch-grass, or surface herbage before ploughing in would 

 do no harm in this way, and destroy much shelter for this, as well as 

 other insect vermin ; and any of the methods of treatment or chemical 

 applications which are known to be of use as preventives of Wireworm 

 attack would also be of service. 



Gas-lime applied in caustic state so as to act first as a destroyer of 

 plant life and insect vermin on the surface of the land, and (after 

 proper exposure to the air) as a safe and serviceable manure, is doubly 

 useful. This may be given at a rate of two tons per acre, and should 

 be applied by being spread evenly on grass-land before breaking up, or 

 on stubble, or other land as required, and left exposed to the air for at 

 least three or four weeks before being ploughed in. Thus a portion of 

 the constituents, which at first do good by their poisonous nature, 

 become changed by the action of the air to sulphate of lime, or gypsum, 

 as manure serviceable on many soils. 



Mechanical measures such as compress the ground and so pre- 

 vent the larvse "travelling" are of use ; and so are the opposite 

 methods of treatment, such as hoeing, harrowing, &c., which act by 

 throwing the earth open and disturbing the grubs and throwing them 

 open to bird attack. But what is commonly most needed is preventive 

 treatment to the ground applied well beforehand. 



