Skip to main content

For farmers and citizen scientists, ways to promote healthy crops and landscape

ST. PAUL, Minn. (4/2/18)—Invasive species cast a damaging shadow in whatever environment they occupy. 

With growing season on the horizon, Extension scientists are asking for Minnesotans help to better understand invasive plants and insects and reduce the harm they cause.

Buckthorn: A double whammy in the invasive world

Thick and bristling with sharp thorns, buckthorn is favorite winter host for eggs of the soybean aphid, an invasive species that poses a yearly threat to Minnesota’s crop. Itself an invasive species, buckthorn overpowers more desirable native plants and grows at an alarming pace.

“Spring is a great time to get tough with buckthorn,” said Extension forestry educator Angela Gupta. Along with the Minnesota Soybean Research and Promotion Council, Gupta has produced two brief videos that demonstrate how to identify buckthorn and methods for its removal. Farmers Rochelle Krusemark of Martin County and Michael Lynch of Watonwan County demonstrate tactics that have worked on their farms.

To learn more, visit

Seeking helpful “mummies” in fight against soybean aphids

wasp and aphid on leaf
Aphelinus certus, the wasp, and soybean aphid.
Photo: Matt Kaiser

Extension and the University of Minnesota entomology department are teaming with the Minnesota Department of Agriculture to identify wasps that are natural enemies of the soybean aphid. 

Volunteers are needed to scout fields in search of the mummy-like black aphid remains left on soybean leaves where the wasp, Aphelinus certus, has done its job. Larvae of the wasps live inside soybean aphids, eventually killing them. 

The wasps, which cannot sting humans, then emerge from the dark “mummy” in order to immediately mate and lay eggs in nearby aphids. Many generations of this wasp occur over the summer.
“We need help from Minnesota farmers,” said Extension entomologist Bob Koch. Last year, citizen scientists scouting fields in 43 counties sent samples of the mummies to the University for further analysis. 

To volunteer, contact graduate student Jonathan Dregni at More information is available at

back side of leaf with aphids on it
"Mummies" left after wasp destroys aphid.

Media Contact: Allison Sandve, Extension news media manager,, 612-626-4077 (office) or 651-492-0811 (mobile)

For more news from U of M Extension, visit or contact Extension Communications at University of Minnesota Extension is an equal opportunity educator and employer. 

Print Friendly and PDF