Asparagus




The Twelve-spotted Asparagus Beetle

(Crioceris 12-punctata Linn) The presence of this insect in America was first detected in 1881, and it is still much rarer and consequently less injurious than the preceding species. In Europe, where it is apparently native, it is common but not especially destructive. The



chief source of damage from this species is from the work of the hibernated beetles in early spring upon the young and edible asparagus shoots. Later beetles as well as larvae appear to feed exclusively upon the berries. The eggs are deposited singly, and apparently by preference, upon old plants toward the end of shoots, which, lower down, bear ripening berries, and they are attached along their sides instead of at one end, as in the case with the eggs of the common species. Soon after the larva hatches from the egg it finds its way to an asparagus berry, enters it, and feeds upon the pulp. In due time it leaves the first berry for another one, and when full growth is attained it deserts its last larval habitation and enters the earth, where it transforms to pupa and afterward to the adult beetle. The life cycle does not differ materially from that of the common species, and there are probably the same or nearly as many generations developed. This species is at present distributed throughout the asparagus-growing country of New Jersey, particularly in the vicinity of the Delaware River, the whole of Delaware, nearly the entire state of Maryland, the District of Columbia, the southeastern portion of Pennsylvania bordering the state line of New Jersey, northeastern Virginia in the vicinity of the western shore of the Potomac River, Staten Island, and Monroe County, N. Y., the last mentioned being the most northern locality known for the species. The mature beetle in life rivals the common asparagus beetle in beauty, but may be distinguished by its much broader wing covers and its color. The ground color is orange red, each wing cover is marked with six black dots, and the knees and a portion of the under surface of the thorax are also marked with black, as seen in Fig. 45, a. The beetle as it appears on the plant when in fruit very closely resembles, at a little distance, a ripe asparagus berry. The full-grown larva is shown in Fig. 45, b. It measures, when extended, three-tenths of an inch, being of about the same proportions as the larva of the common species, but is readily separable by its ochraceous orange color. Fig. 45, c, shows the second abdominal segment of larva, and d same of the common asparagus beetle, much enlarged. Remedies.--The remedies are those indicated for the common asparagus beetle, with the possible exception of caustic lime and other measures that are directed solely against that species, but the habit of the larva of living within the berry places it for that period beyond the reach of insecticides. The collection and destruction of the asparagus berries before ripening might be a solution of the problem, but it is questionable if recourse to this measure would be necessary, save in cases of an exceptional abundance of the insect.





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