Figure 4. -- 



Adult spear-marked black 

 moth, about 1-1 /2X. 



The life history of the spear -marked black moth, as determined by the 1958 

 study, is given in Figure 5. 



To estimate the effectiveness of an aerial spray application for controlling this 

 insect, a spray test was made on the ground using an aerial spray formulation 

 of DDT. The spray consisted of one pound of technical DDT, one-quarter gallon 

 of Velsicol AR-50, and #2 fuel oil to make one gallon. The spray was applied 

 with a compressed air sprayer at the rate of approximately one gallon of spray 

 per acre. The spray was 98.3% effective in controlling third instar larvae. 



A water emulsion of DDT was tested for its effectiveness as a ground spray for 

 use on ornamentals and along roadsides. The test emulsion consisted of one 

 quart of 25% DDT in three quarts of water. The spray was applied with a com- 

 pressed air sprayer to the runoff point against third instar larvae. Complete 

 control was obtained. 



^ Noteworthy Insect Outbreaks --During the past two years the Alaska spruce 

 beetle built up to epidemic populations in the white spruce stands of the Kenai 

 Peninsula. Heavy tree loss is occurring in the northeastern part of the Kenai 

 National Moose Range and within several drainages of the adjacent Chugach Na- 

 tional Forest. Several thousand trees within the National Moose Range are 

 believed to be currently infested. On the more accessible National Forest areas 

 an estimated 1,000 trees are currently infested. Losses on the Moose Range are 

 not considered undesirable because spruce is a hinderance in the management 

 of moose. Control on other lands is being considered. 



The spear-marked black moth outbreak, that started in 1957, increased in 

 severity in paper birch during the early summer of 1958 but declined sharply 

 in mid- summer and remained low in 1959. In 1958 the infestation extended over 

 a gross area of 5, 829, 000 acres in the vicinity of Fairbanks, with heavy defol- 

 iation occurring on 333,000 acres. The sharp population drop was caused by a 

 granulosis virus and by insect parasitism. Control was not attempted. 



The black-headed budworm and hemlock sawfly are again showing signs of a 

 general buildup in the hemlock-spruce stands of Southeast Alaska. 



12 



