The Western Cedar Pole Borer Or Powder Worm
Total Page:16
File Type:pdf, Size:1020Kb
R EC V Z- Í- ^ MAR ^ ^ ^'^^ CO0»S TECHNICAL BULLETIN NO. 48 ' FEBRUARY, 1928 UNITED STATES DEPARTMENT OF AGRICULTURE WASHINGTON, D. C. THE WESTERN CEDAR POLE BORER OR POWDER WORM By H. E. BxTBKE Entomologistj Division of Forest Insects, Bureau of Entomology^ CONTENTS Page PsLge Introduction 1 Description of the insect 7 History 2 Life history 11 Economic Importance 3 Habits 11 Distribution 4 Seasonal history 12 Food plants 4 Natural enemies 13 Character of the injury 5 Methods of preventing loss 13 Indications of injury 6 Summary 13 Cause of the injury 6 Literature cited 14 INTRODUCTION Hundreds of the finest standing trees of the western red cedar or giant arbor vitae (Thuja plicata Don.) in the Paciñc coast region of Oregon, Washington, and British Columbia have a large proportion of their timber riddled by the flattened, oval worm hcues of the western cedar pole borer or powder worm {TrachyheU hlondeli Mars.). These holes wind through the sapwood and heartwood of the main trunk of infested trees and render the timber almost worth- less for the higher grade uses, such as shingles, cooperage, doors, furniture, finishing, cabinetmaking, shipbuilding, and other high- frade products, for which it is otherwise especially suited. Worm oles do not seem to injure cedar timber seriously for use for fencing, sills, posts, piling, poles, or other construction purposes. Worm holes in timber, however, give it the appearance of being damaged, and, even if it is just as good as sound timber for certain purposes, the price is lowered and the manufacturer suffers a real loss. iThe writer Is under obligations to the following fellow workers for assistance In the Investigations treated in this bulletin : B. C. Van Dyke, S. A. Rohwer, Ralph Hopping, and W. S. Fisher for suggestions on classification ; W. J. Chaml)erlin for the loan of specimens of the beetle; George Hopping for specimens of the laryae; J. H. Baxter & Co. for speci- mens of the work of the borer ; A. G. Böving for a critical review of the larval descriptions and drawings ; and Miss E. T. Armstrong for the drawings of the Insect. The drawings ©f the work were made a number of years ago by the Jate J. F. Strauss. G9721—28 1 2 TECHNICAL BULLETIN 48, U. S. DEPT. OF AGRICULTURE HISTORY As will be seen by the following history as recorded in literature, the western cedar pole borer or powder worm {Truchykele hlondeli Mars.), as now recognized by taxonomists, is one of a group of five more or less closely related species which form the genus Trachykele of the family Buprestidae (flat-headed borers) of the order Cole- óptera (beetles). The genus Trachykele, with the species hlondeli as the type, was named and described by Marseul {32Y in 1865 from a specimen said to have been found in the Custom House at Paris, France, by M. Blondel. The specimen was supposed to have emerged from the wood of a cedar of Lebanon. Gemminger and Harold {17) listed the species in 1869 with the locality New Orleans, and placed with it in the genus Trachykele the species Dicerca lecontei^ which had been listed by Dejean (i^) in 1837. described by Gory {19) as Buprestis leeontei in 1841, and mentioned by Leconte (^7, 28^ 29) as Buprestis leeontei in 1858 and 1859, and as Dicerca leeontei in 1863. Saunders {SJf) in 1871 changed the locality of hloTideU to Mexico. Crotch (i^, 13), writing in 1873, said the species appeared to be North American and might be the same as Dicerca leeontei Gory. He listed both species under the genus Trachykele in his check list. Stein and Weise {35) in 1877 gave Georgia as the locality for hlondeli and said that the species was introduced into Europe. Waterhouse {36) in 1882 figured hlondeli for the first time and stated that it was said to come from Mexico, but expressed some doubt about that locality. LeConte and Horn {30), in their " Classification of the Coleóptera of North America" published in 1883, gave characters for separating Trachykele from other members of the group Buprestes. Heyden, Keitter, and Weise {23) listed hlondeli from Georgia in 1883 and noted that it had been introduced into Europe. Henshaw {21) in 1885 considered the species to be North American. Kerre- mans {24j 25^ 26) stated in 1892 that hlondeli Mars, is the same as leeontei Gory and that the habitat is Mexico, and repeated his state- ments in 1903 and 1904. He gave no evidence for his positive state- ments and said he had never seen either species. Hamilton {20) wrote in 1894 that the species hlondeli had been omitted from the latest European catalogue because it did not successfully acclimate in Europe when introduced. Wickham {37) in 1902 recorded leeontei from Garland, Colo., and Blaisdell in 1903 from Tulare County, Calif. Fall {16) in 1906 questioned the localities of Mexico and New Orleans and recorded specimens of hlondeli from Santa Fe, N. Mex. He gave a complete review of the genus and described two new species, opulenta close to hlondeli^ and nimbosa close to leeontei. Fall and Cockerell {16) listed hlondeli from Santa Fe, N. Mex., in 1907. Wright and Coolidge {38) in 1908 listed opulenta from Placer County, Calif. The present writer noted in 1908 that all the species of Trachykele apparently live upon cedar of some kind; and in later papers {1^ 2^ 3^ 4, S, 6, 7) he described for the first time the larvae and work of 2 Reference is made by italic numbers to " Literature cited," p. 14. THE WESTERN CEDAB POLE BOREB OR POWDER WORM 3 hlondeti^ lecontei^ opulenta^ and nimbosa^ described a new species, hartmani^ and recorded numerous observations on the distribution, habits and host plants of the various species. Casey {8), writing in 1909, gave " Pacific coast to Gulf of Mexico " as the distribution for the genus Trachykele. Gibson {18) reported hloiidéli from Goldstream, B. C, in 1914, and Chrystal {11) reported it in 1917 as a destructive wood boret of green and dead cedar in British Columbia. Chamberlin {9) in 191T noted the occurrence of opulenta and nvmhosa in northern Cali- fornia, and in 1924 {10) reported serious damage by hlondeU to^cedar in western Oregon. Herbert {22) in 1920 recorded 'blandeli as an associate of the cypress bark scale, Ehrhomia cupressi (Ehrhorn), on Monterey cypress. Leng {31) in 1920 listed opulenta^ hlondeli^ nimbosa^ and lecontei from North America, and Nicolay {S3) in 1921 recorded hartmani in his list of new North American beetles. ECONOMIC IMPORTANCE Supervisor G. T. Allen of the Mount Eainier National Forest, in a letter to the Forester dated June 11, 1905, said : "A very large part of the cedar (in this forest) is worm eaten." Again on Jime 29, 1905, in a letter to Doctor Hopkins, he wrote : " The worm eaten trees often are green and apparently thrifty when the timber is so full of holes as to be of little value." And again on July 12, 1905 : " I think it very possible that the insect does not attack living trees, but the holes are very common in both green and) dead timber not long after the tree has been felled. As the timber is spoiled for shingles and most other purposes; and, as the insect appears to be common in certain localities on this reserve and its vicinity, I should like to be informed of its name and whether it attacks the living trees." In June, 1905, a shingle man near Portland, Oreg., sent in shin- gles from cedar heartwood, which were badly riddled by the flattened oval worm holes. (Fig. 2.) He reported a large amount of timber severely damaged. During the same year the shingle men at a mill at Hoquiam, Wash., struck because so much of the timber that they had to handle was worm eaten. As they worked by piece work, all of the worthless stuff that went through their hands was a direct loss to them, repre- senting that much time thrown away. In Pialschie, Wash., in 1906, the writer found the mines numerous in both the sapwood and heartwood of standing dead and living trees, and in piling used for a railroad bridge. In 1912 B. T. Harvey reported that in the lower Columbia Kiver Basin in Oregon worm holes often reduce from 30 to 50 per cent of the best grades of cedar to lower-grade material. Some- times fully 70 per cent of the tree is entirely destroyed as far as its value for shingles is concerned. During 1914 and 1915 the writer found many juniper trees in the Lake Tahoe section of California with the wood of the trunks badly riddled by the worm holes of this species. As the juniper has a probable value as a producer of pencil wood, this damage in time may become the deciding factor in determining its commercial value. 4 TECHNICAL BULLETIN 48, U. S. DEPT. OP AGRICT7LTUBE In 1917 Chrystal {11) reported worm holes as a source of con- siderable loss to both green and dead cedar in British Columbia. In 1924 Chamberlin (lO) wrote that the work of the borer was common in Oregon from the coast up to about 2,000 feet elevation, and that some shingle manufacturers estimated their loss at from 15 to 30 per cent of the cut on limited areas. During the last few years manufacturers of cedar poles in Wash- ington and British Columbia have reported numerous cases of wormy timber and have requested information on the habits of the worm causing the damage. DISTRIBUTION Trachyhele hlomdeli has been recorded from the following locali- ties: Lebanon, Turkey (Marseul) ; New Orleans, La.