AMES, Iowa — Hungry pests begin to emerge with warm spring weather and spread to foraging spots such as trees, shrubs, gardens and even crop fields. To raise awareness of damaging pests, the United States Secretary of Agriculture Sonny Perdue issued a proclamation making April 2019 “Invasive Plant Pest and Disease Awareness Month.”
“Proclaiming an awareness month does just what it is supposed to do, bring awareness to a very important issue,” said Laura Iles, director of the Plant and Insect Diagnostic Clinic at Iowa State University. “Invasive plant pests and plant diseases have a huge impact on our lives by harming plants we rely on to eat, make a living, shade our homes, protect our environment and so much more.”
These plant pests and diseases — hungry pests — are called invasive due to the fact that their origins are from outside the geographical boundaries of a particular location. These hungry pests include various species of fungi, bacteria, moths, beetles, flies, caterpillars, ants, worms and even snails — all of which can be easily transported from one location to another when moving outdoor gear or moving homes. One example of an invasive plant pest that is widely talked about in Iowa is the emerald ash borer, as it is neither native to Iowa nor North America.
This species of beetle is native to Asia and is believed to have arrived in the U.S. by wooden shipping pallets. Emerald ash borer is responsible for the destruction of millions of ash trees in 30 states. It’s mostly moved from location to location by humans moving firewood that contain larvae or pupae. Emerald ash borer larvae kill any unprotected ash tree. Although there is a biological control program started, the only way to protect an ash tree is with insecticide treatments.
“Many invasive pests are able to hitchhike on items that us humans move around,” Iles said. “For example, the spotted lanternfly can lay egg masses on vehicles, camp chairs and other items. Their egg masses look like some mud splatter and may go unnoticed to the untrained eye. These egg masses can contain up to 50 eggs, enough to start an infestation.”
Keep these pests in mind while cleaning and maintaining gardens and adding new plants this spring. It’s also important to purchase new plants from nurseries that follow all precautions to prevent the movement of invasive pests. Be cautious buying plants from private individuals through websites or taking plants dug from a yard across state lines.
The USDA Animal and Plant Health Inspection Service offers a program to educate the public about invasive species, and suggests small everyday steps to protect native species. The program also features a state-by-state breakdown of pests based on host plants present in the state, and confirmed pest sightings.
To determine or confirm identity of a hungry pest or disease in Iowa, collect a sample of the pest or take well-lit, in-focus pictures of the pest and submit to the Plant and Insect Diagnostic Clinic.
Photo: A gypsy moth caterpillar feeding on a white oak tree. Gypsy moths are an invasive species and can cause damage to native tree species. Though not confirmed in Iowa, the moth’s presence has been confirmed in several bordering states.