Description

• Hoplia callipyge is a species of hoplia beetle that feeds on magnolia flowers as well as the flowers, leaves and fruit of several other plants such as grapes, willow, beans and vetches. They are especially drawn to white or yellow flowers and, when they're disturbed, they pretend to be dead and fall to the ground. Adult beetles are small and only grow between 1/4 and 3/8 inch long. They have dark, reddish-brown bodies that look iridescent in the sun, with luminous silver and green colors that come from the presence of silvery scales. Hoplia beetles are related to Japanese beetles, for which they are often mistaken. Beetle larvae are white, crescent-shaped grubs that live in the ground.
  
  

Damage

• Hoplia beetles eat the buds and flowers of magnolia trees, chewing round holes in the petals. Although they eat the leaves of other plants, they don't eat magnolia leaves. Grubs eat decaying vegetation and roots found in the soil, but they don't eat the roots of woody plants such as the magnolia tree.
  
  

Life Cycle

• Female beetles lay glossy, white eggs in pastures, along fences and other places where the vegetation hasn't been disturbed and, when the larvae hatch, they burrow into the soil to feed on roots and decaying vegetable matter. Larvae overwinter in the soil and emerge as adults in the spring. Adult beetles fly to gardens where they feed on the flowers, leaves and fruit of various host plants. After about a month of feeding, they're ready to lay their eggs, starting the cycle all over again. They produce only one generation each year.
  
  

Control

• Control hoplia beetles by picking them off magnolia blossoms by hand and dropping them into a pail of soapy water. You can also place white, 5-gallon buckets of water throughout your yard or garden, after adding a few drops of detergent to the water. Beetles will be attracted to the buckets and fall into them, where they will drown. Systemic insecticides aren't effective against hoplia beetles because not enough insecticide reaches the flowers where they feed. Chemical insecticides such as carbaryl are available for use, but should be used cautiously because they will also kill honeybees and may enter your drinking water, via groundwater.