Page:The Olive Its Culture in Theory and Practice.djvu/131

Rh borer. The feet are short and robust, and the head is of a light green color.

The Psylla counts two generations which succeed each other in the spring, during the evolution of the blossoms. At the commencement of the warm season some of the insects die, while others of both sexes remain through the summer. During the autumn and winter they seek shelter on the under part of the leaves, or stalks of the tender shoots, and shield themselves there as best they may from the storms.

As soon as the olive blossoms in the spring, the mating of the Psylla takes place, and the female deposits her eggs on the flowering branches, enveloping them with a cottony material. The larvæ soon appear, separating themselves at once from the cottony covering, and attacking the blossoms from which they draw their aliment. In twenty days from hatching, they transform themselves into perfect insects. In the warmer localities the Psylla appears about the middle of April, but in very forward seasons it frequently happens that the second generation is at work by the last of that month. The Psylla of the first generation commence the work of propagation at once by attacking fresh branches, and continuing without stoppage, till the first of July. A part of the insects then die, whilst others survive until the succeeding spring. The larva and the chrysalis prefer remaining in the same place; when molested they move with difficulty, and even the insect when disturbed will neither hop nor fly with much agility.

This insect nourishes itself by sucking the honey of the blossoms.

The blossoms attacked by it either wither away, or are slow of development, and produce few olives, and these few of a poor quality.

The early spring rains, if followed by high winds, have a tendency to dislodge the cottony substance containing the eggs or larvæ, and many of them perish in this way, but the radical remedy for their distructiondestruction [sic] is to cut away the infected branches, although this method is both difficult and costly. All branches