TREE INSECTS AND THEIR CONTROL 211 



SAP-SUCKING SCALE INSECTS 



Oyster-shell Scale 



(See description and remedies under Elm) 



San Jose" Scale 



(See description and remedies under Ash) 



MAGNOLIA 



SAP-SUCKING SCALE INSECTS 



Magnolia Soft Scale 



Remedies. Spraying is the best means 

 of controlling this scale. The 

 spray should be applied late in September, 

 at the time when the young have just 

 made their appearance. Ten per cent, 

 kerosene emulsion has been found effec- 

 tive, as has miscible oil solution. Winter 

 spraying with undiluted crude petroleum 

 is advocated by some authorities as an 

 efficient means of control. 



Habits This scale encrusts the 



and branches of the Magnolia and 



Damage. Tulip tree so thickly at times 

 as to cause the tree to sicken 

 and die. After spending the winter on the 

 bark the scales feed there during the 

 spring and summer and produce a new 

 generation toward fall. In September the 

 young insects settle so densely on the 

 twigs as completely to hide the bark. At 

 this time the young may be seen crawling 

 about, preparing to settle. The fully 

 grown scale is a vivid gray or light brown, 

 knotty and prominently raised. The 

 young scale is black. In addition to the 

 damage caused by the feeding, the scale 

 secretes an offensive honey-dew which 

 invites fungus growth and clogs the pores 

 of the leaves. 



MAPLE 

 LEAF-CHEWING INSECTS 



Forest Tent Caterpillar White-marked Tussock Moth 



Bagworm Brown-Tail Moth 



(See descriptions and remedies under Elm) 

 Green-striped Maple Worm 



Habits While not prevalent every 



and year, this worm does serious 



Damage, damage to the Maples at 

 times and has been known to 

 strip trees of all their foliage. The moth 

 appears in May or June, an insect with 

 woolly body, pale yellow, and having a 

 wingspread of two inches. Eggs laid on 

 the underside of leaves hatch into cater- 

 pillars within ten days. The caterpillar is 

 smooth, a pale yellowish green, and grows 

 to be two inches long; it is striped length- 

 wise with dark green and has long horns 

 back of the head. The worm feeds on 

 leaves. 



Remedies. Natural enemies, including 

 birds and insects, serve to 

 keep this worm in check for the greater 

 part of the time. . When a tree becomes 

 infested it should be sprayed with lead 

 arsenate as soon as the caterpillars make 

 their appearance. Prompt action is need- 

 ed to prevent destruction of the foliage. 

 To pick by hand such caterpillars as may 

 be in reach is helpful in ridding young 

 trees of this enemy. 



