. The American florist : a weekly journal for the trade. Floriculture; Florists. Chrysanthemum Midge. Fig. 2.—Chrysanthemum Leaf Showing Gall. pest, they should be thoroughly ex- amined before they are placed in a house containing a collection of chry- santhemums. Figures '1 and 3 illustrate the galls made by the larvae or maggots of the midge. However, in the case of a re- cently infested plant, the galls are very small and diflicult to detect and would naturally require careful exam- ination to discover their presence. The fully developed gall averages about . inch in length and 1-25 in
. The American florist : a weekly journal for the trade. Floriculture; Florists. Chrysanthemum Midge. Fig. 2.—Chrysanthemum Leaf Showing Gall. pest, they should be thoroughly ex- amined before they are placed in a house containing a collection of chry- santhemums. Figures '1 and 3 illustrate the galls made by the larvae or maggots of the midge. However, in the case of a re- cently infested plant, the galls are very small and diflicult to detect and would naturally require careful exam- ination to discover their presence. The fully developed gall averages about . inch in length and 1-25 inch in dia- meter at the base, and is placed at an acute angle on the surface of the plant tissue. They occur on the leaf, leaf petiole or stem, and if present in numbers cause the plant to be de- formed, as shown in figure 3. Some .")0 odd commercial single stem and pompon varieties have been found to be infested with this midge. In fact, practically all cultivated chrysanthe- are susceptible to attack al- though the degree of infestation ap- pears to be more severe with some varieties than with others. For the most part the adults which are about 1-12 of an inch in length, exceedingly delicate and provided with long slender legs (figure 1) emerge after midnight, and egg laying takes place very early in the morning. The life of the male midge is usually less than a day; whereas females have been kept alive from one to three days. The entire life cycle is passed in from four to six weeks, there being several generations a year with frequent over- lapping of broods. The eggs are very small, orange col- ored, and are deposited on the tender new growth. They hatch within 'five days, and the larvae or maggots, which are very small and vary in color from a transparent white to pale orange, enter the tissues of the plant in from one to three days. The inter- val between this period and the emer- gence of the adult is passed within the gall. As yet no satisfactory method o
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectfloriculture, bookyea
