16 



ground near the plant or on the stalk. The young larva eats its way into 

 the young plant at the point where it enters the ground. The grub 

 bores upward and as it nears maturity eats outward until it is almost 

 through the bark of the plant, lea^ ing only a thin shell. It then spins 

 a small cocoon of white silky material and transforms into a pupa. 

 From this pupa emerges a small dark giay moth which is about 0.5 

 centimeters in length. Plants that contain larvse of this species are 

 always stunted and the leaves droop. Often the plants are blown over 

 by a light wind, as the entire heart or pith of the stalk is eaten out. 

 When such plants are noted they should be pulled up and burned. It 

 may be possible to combat these insects by dipping the plants at the 

 time of transplanting from seed bed to field in a strong mixture of 

 lead arsenate, which would probably kill the insects as they eat their 

 way into the stalk. This is one of the worst enemies of young tobacco 

 plants, for the entire plant is destroyed by the one insect, and should 

 the species ever become numerous it will constitute quite a check to 

 tobacco culture. 



There are other insects which affect tobacco, such as leaf-feeding beetles 

 and some sucking bugs, but as they do not confine their attention entirely 

 to the tobacco plant the damage done is not so great. 



Some insects which are really beneficial are killed through ignorance, 

 noticeable among these are the small lady-bird beetles and the larva? 

 of the sun flies. Both of these feed on the colonies of plant lice which 

 attack the tobacco, especially the beetles, which feed on them both during 

 the larval and mature states. The sun fly larvae feed on the plant 

 lice and destroy them in great nxmibers. As plant lice are indirectly 

 responsible for considerable loss of tobacco by the growth of a fungus 

 upon the leaves, it will be seen that the beetles and sun flies should be 

 protected rather than killed. 



TOPPING AND SUCKERING. 



It should be remembered that the ultimate object of the tobacco 

 plant itself is to produce seeds and not leaves. After the flowering bud 

 appears at the top of the plant much of the nutritive substance, that 

 would otherwise be stored in the leaves, goes to the top of the plant 

 for the development of the seeds and the small top leaves; the lower leaves 

 will then be thin and light. If it is desired that the lower leaves should 

 be heavier, then the seed pods should be removed. 



Just how much of the top of the plant should be removed with the 

 flowering bud depends upon the variety of the tobacco, the climatic con- 

 dition at the time the operation is performed, the physical condition 

 and fertility of the soil, the vigor of the plant, and the quality of leaf 

 it is desired to produce. 



Wlien tobacco is grown on a fertile soil, and it is desired to produce 

 a liglit, thin leaf for cigar-wrapper purposes, the plants should be topped 

 high ; tobacco grown on poor soil should be topped lower. 



