disease occurs throughout the whole of Southern Ontario and extends north to the 

 north shore of Lake Nipissing. Further spread to the north will be very limited 

 because of the scarcity of elms in that part of the Province. However, in 1965 the 

 disease was found for the first time on Manitoulin Island and at Spanish, thus 

 indicating the start of its inevitable spread westward toward Sault Ste. Marie. 



CONTROL 



Efforts to control forest pest problems are conducted in natural stands as well 

 as in artificially established plantations. 



For the past few years the forest insect causing greatest economic damage 

 has been the white pine weevil. Control methods during 1965 were confined to 

 spraying with knapsack sprayers, and hand clipping and burning infested leading 

 shoots. A total of 3,300 acres of young white pines was treated. 



Approximately 2,600 acres of plantations were sprayed from the ground for 

 control of sawflies, principally the red-headed pine sawfly and the European pine 

 sawfly. 



Small acreages of sod-covered sites were treated for control of white grubs and 

 mice, where these pests threaten the survival of newly planted trees. 



The major tree-killing disease in the forests of Ontario is the blister rust of 

 white pine. A substantial control program, which is tied into the broader intensive 

 management of white pine, has been in progress for many years. The disease is 

 controlled by using the herbicide 2,4, 5-T to kill the obligate alternative host plants, 

 wild currants and gooseberries, in the immediate vicinity of the pines. In 1965 

 more than 5,300 acres of high-value young pine stands were protected against the 

 blister rust in parts of the Sault Ste. Marie, North Bay, Tweed, Kemptville and 

 Lake Huron Forest Districts. 



The fomes root rot, a killing disease relatively new to Ontario, with a potential 

 for causing high losses in natural stands and plantations, is causing concern in 

 several areas of eastern North America. In addition to the known locations of the 

 disease in some pine plantations in the Lake Erie and Lake Simcoe Districts, the 

 fungus was found for the first time in the Northumberland County Forest, Lindsay 

 District, in 1965. It is possible to control the disease by treating stumps during 

 thinning operations, and approximately 475 acres were treated in 1965. 



Early in 1965, a new preventive treatment for Dutch elm disease was 

 approved for use in the U.S.A. The treatment involves injection of the systemic 

 insecticide "Bidrin" into each elm tree to kill the disease-carrying elm bark 

 beetles. 



The chemical was brought into Ontario for experimental purposes, and the 

 Department participated in a program to test its effectiveness by treating a total of 

 270 elms across southern Ontario from Windsor to Kemptville. 



Radio Communications 



A decided increase in the number of radiograms transmitted over the Radio 

 System was recorded for 1965. A total of 108,063 messages was handled for a 

 total of 5,066,371 words representing increases of 18 percent and 91 percent 

 respectively over 1964 totals. In addition to this traffic many thousand unrecorded 



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