• Protect your plum trees from insect infestation by regularly inspecting them.plum image by dinostock from Fotolia.com
  
  Some common pests that affect the Newport plum tree are aphids, borers, mealy bugs and tent caterpillars. The Southern Group of State Foresters writes that Newport plum trees, or Prunus cerasifera, are very susceptible to insect infestation and the diseases which many common pests bring with them.
  
  

Aphids

• Aphids occur in colonies. Though it is rare for an aphid colony to kill a fully grown tree, they can cause damage. They feed on the plant sap, sucking it out with piercing mouth parts. Affected leaves will wilt and turn yellow from the removal of the sap. Aphids produce large amounts of liquid waste called honeydew. Honeydew encourages the growth of mold, which can slowly suffocate a full-grown tree. Examine your tree buds weekly to try and detect an aphid infestation early. According to the University of Kentucky, if 5 percent or more of the tree has aphids on it, take control measures such as spraying or acquiring lady bugs.
  
  

Borers

• Borers are the larval stages of insects such as beetles and moths. Many types like the round headed apple tree borer attack fruit trees. They feed on wood instead of plant material and bore into the trees' woody parts. The bark turns dead and dark near areas of borer infestation. They can kill young trees and seriously injure adult trees. Though borers tend to attack disease- or winter-weakened trees, they have been found on healthy specimens as well. Insecticide is the best way to prevent further damage. It must be applied when the adults are laying eggs. The timing is critical, says the University of Missouri.
  
  

Mealy bugs

• Mealy bugs are small, rubbery insects that excrete a white powdery substance that sometimes looks like wool or cotton. They stick to the plant and devour every part of it from foliage to roots. They are known, according to Cactus Art Nursery, to smother and kill large specimens, including plum trees. These pests return again and again. They spread pathogens and disease from plant to plant. Washing the foliage and removing the visible parts of the infestation helps. Pesticides may be necessary if the infestation has gotten too large.
  
  

Tent Caterpillar

• Tent caterpillars spin silvery webs on crabapple, plum, maple and cherry trees. They feed on tree buds and foliage and when numerous will cause considerable foliage damage. The web nests these caterpillars build grow large and become visible from roadsides and neighboring fields. To reduce the population of these insects, seek out the egg masses and remove them during winter to prevent spring hatching. Also, throughout the growing season, remove all visible nests.