STRAWUERRY CROWN GIRDLER AND OTHER INSECTS. 219 



Department of Agriculture, Bureau of Plant Industry, for exam- 

 ination. Mr. C. O. Townsencl, acting pathologist and physiolo- 

 gist of that bureau, stated the trouble to be due to nematode 

 worms. 



Although worms are not insects, the nature of their attack and 

 the remedies applied bring them into a closer relation with work 

 pertaining to insects than any other department of the Station, 

 and a record of this case is included with notes on insects. 



As Mr. Townsend's letter is of interest and as the preventa- 

 tive means he recommended apply with equal force to millipedes, 

 concerning which complaints from greenhouses frequently reach 

 the station, the letter is quoted in full : 



" The swellings on the roots were caused by the root-knot 

 nematode, Heterodera radicicola. These swellings, after the 

 nematodes have reached maturity and laid their eggs, decay and 

 bring about thus the death of the plant. They also reduce the 

 vigor of the plant before the period of decay is reached by 

 checking the water supply and diminishing the root growth. 



" There is no certain method known by which the nematodes 

 can be killed in the roots of this plant without injury to the plant 

 itself. Experiments were conducted at Washington some years 

 ago with roses badly infested with nematodes, using a i-per cent 

 solution of formalin. This proved eiTective in destroying the 

 pests and, although it caused the shedding of the leaves, did not 

 kill the rose plants. Whether similar treatment would be 

 destructive to the gardenia plants or not can be determined only 

 by experiment. The plants should be hardened ofT somewhat 

 for a week or two before the experiment is made. 



" The trouble can be avoided by sterilizing the soil in which 

 the plants are to grow and then using only such plants as are 

 absolutely free from any signs of root-knot. This sterilization- 

 can best be effected, as described in bulletin No. 55 of the Hatch 

 Experiment Station, by the use of live steam from a boiler with 

 a pressure of 40 to 60 pounds. This is conducted through 

 perforated pipes laid in the bottoms of the beiii-hes, the steam 

 being passed into the soil until it has all l-ccn heated to the 

 temperature of boiling water. This suffices to kill not only the 

 nematodes but also various destructive fungi." 



Tarnished plant bug. The tarnished plant bug was present 

 in the usual numbers this season and during the spring caused 



