98 Habits of the Tomato Moth 



alternately in an isolated house for six nights. On the three nights when 

 three were used eight moths were caught, and on three nights when 

 six were exposed the catch was 16. The conclusion drawn from these 

 experiments was that in order to obtain the best results with this bait, 

 jars should be placed every 40 feet down the houses: that is six to each 

 200-foot house, one at each end, and four others evenly distributed. 



The fluid in the jars evaporates slowly in the greenhouses, and the 

 traps remain effective as long as it covers the bottom. In the work just 

 described the depth of the fluid varied from an inch to an inch-and-a-half , 

 and it was found necessary to renew it every third or fourth week. The 

 only attention the traps require during the interval is the occasional 

 removal of the dead moths. These should not be dropped in the houses 

 where they would prove a counter-attraction to the traps, but should 

 be collected in vessels and thrown outside. In mixing the material, one 

 part of treacle by volume should be placed in a vessel with two parts 

 of ale, the exact proportion not mattering, and the mixture should be 

 poured rapidly backwards and forwards from this into another vessel 

 until it runs smoothly. It should then be distributed into the jars and 

 the sodium fluoride added separately to each, as it dissolves very slowly. 

 The amount that can be picked up conveniently on a sixpence (about 

 3 J oth of an ounce) is required for three fluid ounces. 



(iv) Destruction of Pupae. 



The picking baskets, especially those lined with sacking, need atten- 

 tion when the season is over, as they harbour pupae. Seven lined 

 baskets were placed in an infested block, and at the end of three weeks 

 were found to contain 24 pupae behind the lining. The practice has 

 been to store these baskets over the winter and to bring them into the 

 houses without attention when the fruit picking begins. The moths then 

 emerge from them and their offspring commence feeding on foliage no 

 longer protected by the early spraying. These baskets should be dipped 

 in boiling water. It was proved by experiment that two seconds im- 

 mersion is sufficient to kill the pupae, while 30 seconds did not harm the 

 baskets. 



Special baskets should always be kept for picking, and those from 

 the market should never be allowed in the houses until they have been 

 treated as described. This applies not only to tomato growing but to 

 all nursery work. There is little doubt but that "red spider," and 

 possibly "white fly" also, may be introduced into a greenhouse with 

 a market basket. Those used for picking should be painted or marked 



