Michigan DNR Warns Of Two New Invasive Species

The threats against Michigan’s native ecosystem continue to grow, with the Michigan Department of Natural Resources announcing two new invasive species that have been added to the watch list. The Water-primrose has invaded Michigan’s waterways, and the Mountain pine beetle is steadily creeping toward the Great Lakes State. 

Michigan is home to many invasive species. The European frog-bit, an invasive aquatic plant, has been removed from the invasive species watch list. While this may sound like good news, it was only removed from the list because it has spread to enough areas that will likely never be able to get rid of it. So, sadly, it was removed, as it is now considered an established species. It still retains its prohibited status, making it still illegal to possess, introduce, import, or sell in Michigan. 

This Beetle Could Destroy Michigan’s Pine Forests 

Even though it has not yet been detected, the Mountain pine beetle (Dendroctonus ponderosae Hopkins) has caused concerns because of its potential to devastate Michigan’s forest ecosystems. Susie Iott, invasive species program specialist with the Michigan Department of Agriculture and Rural Development, warns, 

White and red pines are primary species in our forest ecosystems, and jack pine serves as critical habitat for the Kirtand’s warbler. If mountain pine beetle were to become widely established in Michigan, it would cause severe losses across multiple industries, including timber products, plant nurseries, and tourism. 

Hot, dry summers and mild winters, in the western United States and Canada, have caused a population explosion that is creeping toward Michigan. The beetle can be transported on infested pine logs and firewood.  

What To Look For 

Since this small (1/4 inch), dark brown to black beetle is hard to identify, look for these signs on any species of pine trees:
• "Pitch tubes" are popcorn-like globs of brown, pink, or white pitch on the tree’s trunk.
• Red frass, resembling fine sawdust, on bark crevices or at the tree’s base.
• Yellow to red needles in the tree’s crown in the summer.
• Evidence of woodpecker feeding, such as missing patches of bark.
• Galleries under the tree’s bark. 

One Sign of The Mountain Pine Beetle Is "Pitch Tubes"

A Pretty Little Plant That Threatens Michigan Waterways 

The Water-primrose is a pretty little plant, with soft, yellow petals, that floats upon the water. But it is also an aggressive species that produces a thick mat that threatens boating or any other water activities. 

It can thrive and spread in shallow water areas that include wetlands and shorelines. As it spreads, its thick mat begins to crowd out important native vegetation. 

What To Look For 

• Water-primrose may be floating in the water or emergent along the water’s edge. 
• Showy yellow flowers with 5 or 6 petals. 
• Upright growth up to 2 ft. and can also spread horizontally. Stems are reddish in color. 
• Leaves are dark green in color, elongated, and may be lanceolate (willow-like) or oblanceolate (spatula-like) in shape. 
• Water-primrose is an aggressive species and can form dense mats along waterways. 

This Pretty Little Plant Is A Threat!

Protect Our Ecosystem: Report The Threat! 

There are two ways that you can help control the invasive species that threaten the Michigan ecosystem 

• Use the Midwest Invasive Species Information Network (MISIN) online reporting tool. 
• Or- download the free MISN smartphone app and report from your phone. 

When making a report, you should note the location of the threat and take photos to aid in verification.