16 THE EEPOKT OF THE No. 36 



gardens. The Keel-backed Cutworm, (Eiixoa ochrogaster Gn,), was most in 

 evidence, 



EooT Maggots. The Cabbage Maggot {Phorhia hmssicae Bonche), and the 

 Onion Maggot {Hylemyia antiqua Mg.)were again present in the Ottawa dis- 

 trict, but the damage was not s6 extensive as in 1915. Some experiments which 

 we conducted in the control of the latter insect by spraying with sodium arsenite 

 indicated that such control is promising, and further Avork along this line will 

 be done as opportunity occurs. Such control is discussed in Bulletin No. 12 of 

 the Entomological Branch, issued in May, 1916. 



The Potato Flea Beetle (Epitrix cucumeris Harr.). In the latter half of 

 June this insect was present in noticeable numbers. Injury to the leaves of tomato 

 was especially complained of. 



The Corn Ear Worm {Heliothis ohsoleta Fab.). A few complaints of injury 

 fo the ears of sweet corn were received in early September. On September 5th 

 larvae in the last stage were found. The work of the caterpillars is seldom noticed 

 until the injury has taken place. Fortunately this insect is not an important one 

 in the Ottawa district. 



The Banded Ips (Ips fasciatus Oliv.). On September 22, I found this beetle 

 present in a few ears of corn in our experimental plots at the Central Experimental 

 Farm. Several kernels in one ear had been destroyed. This injury is an unusual 

 one, and so far as I know has not previously been reported in Canada. Similar 

 injury has been recorded in the United States. 



The Salt Marsh Caterpillar (Diacrisia acraea Dru.). This woolly bear 

 was fomvd in small numbers (August 11th) feeding on leaves of cabbages at River- 

 meade, close to Ottawa. Although this caterpillar has a wide range of food plants 

 the injury it causes is local. It can hardly be classed as a pest of importance. 

 Handpicking will usually be sufficient as a control measure. 



The Parsnip Webwokm (Depressaria Jieracleana DeG.). At the Central 

 Experimental Farm, the Dominion Horticulturist reported, on July 10th, an out- 

 break of the caterpillars of this insect in a patch of parsnip which he was growing 

 for seed purposes. The larvae were numerous, on one day 170 were removed by 

 hand from the plants. 



The Zebra Caterpillar (Ceramica pida Harr.). An interesting outbreak 

 of this well-known caterpillar occurred in eastern Canada during the autumn of 

 1916, In some sections the larvae were present in thousands, stripping the tops of 

 turnips, and also injuring other plants, chiefly mangels and cabbages. One out- 

 break which occurred near Ottawa effected particular damage to rhubarb. 



The Ash-Gray Blister Beetle {Macrohasis unicolor Kby,). Reports of 

 injury by this blister beetle to potatoes were received in early July. In one field 

 which I visited on July 13th many of the plants had been entirely defoliated. Num- 

 bers of the beetles were present on the vines. Unfortunately, they have the habit 

 of appearing suddenly and oftentimes eating the entire foliage of plants upon 

 which they alight in a day or two. One grower protected his potato crop by dust- 

 ing with arsenate of lead. 



Attacking Fruit a^d Forest Trees. 



No special outbreaks of insects attacking fruit or forest trees came to my atten- 

 tion during the season. The Pear-leaf Blister Mite (Eriophyes pyri Pag,) was 

 found freely on the foliage of apple on July 11th. The Black Walnut Caterpillar, 



