44 SOME INSECTS INJURIOUS TO TRUCK CROPS. 
first favorable place that they find. This early hibernation is usually 
temporary, and when the first warm day comes they emerge from 
their hibernating places and hop around on the ground, retreating 
again when it becomes cool. 
PLACES OF HIBEE^ATIOX. 
During the winter the beetles were observed hibernating in cracks 
in the trellis poles, under the siring of the string pegs, in the hollow 
vine stub>. in the grass and weeds, and in the soil. 
Beetles in poles. — The beetles were first observed to be hibernating 
in the trellis poles. By lifting the slivers they were found wedged 
between the slivers and the solid wood, some were dug from rotten, 
porous portions of the poles, and a few were observed under the bark. 
Many were found in the deep cracks, but the largest number were 
under the slivers and in the rotten wood. As shown by Table III 
the majority of beetles hibernated close to the ground. They ac- 
cepted the first shelter that they came to. and some even entered 
slivers and crawled down below the surface of the soil. 
Table III. — Position of hop flea-beetles in the poles. 
First foor 1S2 
Second foot 152 
Third foot 79 
Fourth foot 33 
Fifth foot 4 
Sixth foot 6 
Seventh foot 
Total number of flea-beetles 456 
Number of poles counted 74 
Average number of beetles per pole 6. 16 
In November. 190S. several poles were taken into the hop kilns and 
heated in order to bring out the beetles that were hibernating 
therein. Most of the poles contained small numbers of them, but in 
one badly splintered pole were found 490 beetles. These results 
led the hop growers to believe that a large majority of the hibernat- 
ing beetles were in the poles. In investigating this point the writer 
had four average poles taken into the kilns and heated. Only 19 
beetles were found in these 4 pole^. The>e. together with other 
results obtained from extensive field counts, proved conclusively that 
the number of beetles which were hibernating in the trellis pole- 
was not dangerously large. 
Beetle* in the vim stubs. — The hollow vine stubs which are left 
when the vine> are cut and burned in the fall are very favorable 
hibernating places, and as many as 16 beetles have been found in a 
