2i8 THE ROSE BOOK 



Another Sawfly, Eriocampa roscB, is black, about an 

 eighth of an inch long, and some of its legs are spotted 

 with white. The larvse are twice that size, and light green 

 in colour, with orange coloured heads. This grub eats 

 the upper surface of the leaves, causes them to die, and 

 then they faU off ; when satiated, the larva passes into 

 the soil and spins a cocoon underground. In some 

 districts these larvae are very numerous, and are known 

 as Rose Slugs. 



Occasionally the edge of a leaf is noticed rolled up 

 or folded neatly over ; this is the retreat of the grub 

 of Blennocampa pusilla, another black, smaU Sawfly, with 

 brown, tinted wings. The grub is short, stout, bristly, 

 and green, with yellow or brown head. Damage is done 

 by it in two ways ; it eats the foliage and prevents the 

 leaves performing their natural functions by rolling 

 them up. 



The tiny, spotted green grub which lies curled up 

 on the under surface of leaves, is from another destruc- 

 tive Sawfly, Emphytus cinctus. That which makes a nest 

 of small pieces of leaves is Lyda inanita, and the holes, 

 to all appearances torn in the leaves, are due to a species 

 called Cladius. Many others may be found in gardens, 

 and they do much damage if left unchecked ; in all 

 .cases, from two to six generations are produced in one 

 season. 



Remedies. — Before dealing with these destructive 

 pests the gardener must know something of their habits. 

 The fly lays her eggs on the branches or foliage ; when 

 the eggs hatch cut the larvse immediately start to feed 



