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of the destructive Larch Sawfly. The larva of the Case Bearer is a tiny 

 caterpillar of most interesting habits. The young caterpillar eats out 

 a portion of a larch needle which it then cuts off, lines with silk, and 

 carries about with it as a portable house covering the hinder part of its 

 body. Leaf after leaf is then excavated by the caterpillar through a round 

 hole cut in the side by the caterpillar to permit the entrance of its body. 

 The caterpillars retire to the twigs before the needles drop in the fall, and 

 pass the winter in their cases, which are firmly attached to the bark 

 with silk. 



When caterpillars are very numerous the dried and yellow skins of the 

 excavated portion of the leaves sadly disfigure the trees, and at times 

 an injurious loss of foliage results. 



Control Measures. — The injury may be prevented by spraying 

 trees which were badly infested the preceding season and upon which 

 the winter cases are numerous, with lead arsenate just as the young needles 

 are appearing in the spring, or, better, with lime sulphur, winter strength, 

 before the growth starts in the spring. Poison sprays are not so effec- 

 tive later in the season, owing to the small extent of leaf surface eaten 

 by the caterpillar; but a spray of kerosene emulsion, one of stock solution 

 to seven parts of water, will kill a great number of them. 



The Larch Woolly Aphis, Chermes strobilohius, is frequently abun- 

 dant on cultivated larches or tamaracs. The trees sometimes appear 

 as though covered with tiny snow-flakes, from the abundance of white 

 wool-like wax threads covering the tiny plant lice feeding upon the leaves. 

 The injury is seldom serious, but may weaken the trees when very abundant. 



Spraying with kerosene emulsion or fish oil soap is the simplest remedy. 



The Larch Saw-fly, Lygaeonematus erichsonii, is sometimes quite 

 destructive to native and European larches. The caterpillar-like larvae 

 feed upon the needles, and if numerous enough, entirely strip the trees 

 of their foliage. Those who own valuable ornamental larches should 

 watch for the enemy, and spray the foliage thoroughly with Paris green 

 or lead arsenate as soon as the larvae appear, and before the foliage is much 

 injured. 



Other leaf-feeding species, such as the Spruce Saw-fly, which quite 

 frequently strips the foliage from ornamental spruces; the Hickory Tiger- 

 moth, common on many deciduous shade trees, and many others, are 

 controlled by poison sprays. 



The Balsam Twi^ Aphis, Mindarus ahietinus, has been very abun- 

 dant in Quebec for several seasons. These tiny plant lice infest the balsam 



