. The Canadian entomologist. Insects; Entomology. 282 THE CANADIAN ENTOMOLOGIST Another system classed under the dry method of control was tried on a small scale in France in 1908 and on a large scale in 1909. This method consisted in suspending in the tree a canvas sac (10-14 inches in length and about 2 inches in diameter), which contained about \x/i lbs. of a mixture of poisoned molasses, saw- dust and bran (Fig. 24). The insecticide transudes directly through the canvas and when a rain washes off the bait, the poisoned molasses filters through again. The proportion of the ingredients used
. The Canadian entomologist. Insects; Entomology. 282 THE CANADIAN ENTOMOLOGIST Another system classed under the dry method of control was tried on a small scale in France in 1908 and on a large scale in 1909. This method consisted in suspending in the tree a canvas sac (10-14 inches in length and about 2 inches in diameter), which contained about \x/i lbs. of a mixture of poisoned molasses, saw- dust and bran (Fig. 24). The insecticide transudes directly through the canvas and when a rain washes off the bait, the poisoned molasses filters through again. The proportion of the ingredients used in the canvas sacs was as follows: Arsenical molasses 71% Sawdust 21% Bsan 8% s-vâ %ln. An excess of bran gives too much porosity to the mixture and favors evaporation. The addition of water to the molasses acceler- ates dessication, a thing to avoid most. To lessen dessication it is necessary to tightly stuff the sacs. After filling the bags, drops of liquid ooze out and this loss can be avoided by allowing the sacs to drain over a vessel for several hours or even two days. The sacs thus prepared are placed in the interior of the trees at a region as accessible as pos- sible. Once during the summer, water was added to the bags on account of the sacs becoming dry at their upper end; this was due to the oozing of molasses through the canvas and to evaporation. Later when the first rains and dew of September occur, the atmos- pheric humidity insures excellent conditions. The cost, including all expenses, amounted to $ per sac. The results obtained in two isolated olive gardens are given in tables V and VI. h ⢠if-'.- -£."â¢'-" 'â Fig. 24.âCanvas sac stuffed with a mixture of bran and poisoned molasses. (After Berlese).. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Entomological Soci
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