XXX THE GYPSY MOTH. 



brick-bat pile was surrounded by a board fence eighteen inches 

 high. This was covered with tarred paper, and before the cater- 

 pillars began to hatch in the pile the paper was covered with a 

 mixture of pine tar, printers' ink and crude petroleum. This 

 fence the young caterpillars were unable to scale. The trees in 

 the brick yard were inspected and the eggs on them destroj'ed. 

 Fire was run through the underbrush, but this did not kill all the 

 eggs. One section of the yard was burned experimentally by 

 spraying the ground with crude petroleum after the brush had 

 been set on fire. On this section no signs of the caterpillars 

 were seen during the year. In other sections, where some eggs 

 survived the burning and hatched, all vegetation was sprayed 

 with Paris' green several times during the season. At the end of 

 the season it was difficult to find any sign of the moth in the yard. 

 Trees and bushes were cut down over a tract of one hundred acres, 

 and fire was run over it. Any spot that escaped the fire was 

 thoroughly burned by the use of crude petroleum. 



The inspection of the towns on the border liu& of the infested 

 district occupied so much time in the spring of 1891 that it was 

 found necessary to neglect until egg-hatching time a large tract 

 near the centre of the district in Maiden and Medford. Time was 

 found, however, to inspect the large trees along the highways and 

 railroads. The eggs found on them were destroyed and the trees 

 were banded with tarred paper, which was kept covered with the 

 mixture used in the brick yard. This prevented the larvae from 

 ascending these trees, and reduced the danger of their being 

 carried out of the district. Most of the trees in the section were 

 sprayed two or three times during the season with a mixture con- 

 taining Paris green, in some places where badly infested they were 

 sprayed four times ; nearl}' all vegetation, in fact, was sprayed. 

 Holes in the tree trunks which offered hiding-places for the larvae 

 were filled with cement. Burlap bands were put about the trees 

 after the caterpillars began to cluster, and by these means the vast 

 increase was kept down. 



As soon as the female moths had laid their eggs and died, a 

 small force of men began destroying the eggs. It was soon 

 noticeable that, while vast numbers of last season's egg-clusters 

 which had hatched were found, very few newly laid clusters ap- 

 peared. Every nook and crevice was searched with the greatest 

 care to discover and destroy all traces of the moth. While the 

 leaves remained on the trees, buildings, fences, woodpiles and all 

 hiding-places near the ground were searched. As the leaves fell 

 the trees were examined and cleaned of eggs. Where the trees 

 were thickly infested the leaves were raked up and burned ; thus 



