Asparagus Beetle
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Asparagus Beetle  There are two species of asparagus beetles which attack and can cause significant damage to asparagus. They are the common asparagus beetle, Crioceris asparagi (Linnaeus), and the spotted asparagus beetle, Crioceris duodecimpunctata (Linnaeus). The common asparagus beetle is 6mm (1/4 inch) in length, has a bluish-black head, legs and antennae tinged with green, a reddish thorax, and wing covers marked by yellowish patches and reddish borders. The larva of the common asparagus beetle is dark gray to olive-green with black legs and head. The spotted asparagus beetle is slightly larger and more robust than the common asparagus beetle. The adults are reddish-orange in color with black antennae, eyes and underside of the thorax. Each wing cover has six distinct black spots. Susceptible Plants- Asparagus Symptoms- Both the larvae and the adults of the common asparagus beetle damage the asparagus plants. The overwintered adults emerge and begin to feed on the tender growing tips of newly sprouted asparagus. They chew holes in the plant and cause a brownish discoloration of the tissue. The grubs will feed on the tender young tips and on foliage. The plant growth is seriously reduced and proper root development prevented, causing a decrease in the size and quality of the crop. The spotted asparagus beetle causes the most injury in the early season when the adults attack the growing tips and sometimes eat the buds of newly sprouted asparagus. The beetles also feed on foliage, eating out irregular areas. The larvae cause little damage because they feed inside the berries. Life Cycle- The adults of the common asparagus beetles overwinter in sheltered places such as piles of rubbish and heaps  of old asparagus tops. The beetles emerge from their shelter and begin feeding on the tender tips of new shoots. They soon lay eggs on the young shoots. The eggs are elongate, oval, and deposited either singly or in rows of two to eight. Later in the season the eggs are laid on leaves and flower stems. The eggs hatch in three to eight days and the grubs begin feeding on the tender tips.When the grubs mature, they drop to the ground and construct a small earthen cell where they transform into pale yellowish pupae. The adult beetles emerge from the pupae. There may be two or more generations a year depending on the climate. The adult spotted asparagus beetles overwinter in piles of debris. Prevention and Control- Pick off larvae and adults. Clear plant debris where beetles may over winter. Biological Control - Beneficial Nematodes   Pesticide Control - Bonide Bon Neem
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