Invasive Plant News

It is impossible to eradicate common buckthorn, an invasive shrub from Eurasia, from the forests of North America.  However, it still makes sense to remove buckthorn from areas where it is particularly harmful to native ecosystems.  One such place is areas of frog and amphibian breeding.  Why?  New research suggests that European buckthorn releases a chemical compound emodin, which is produced in the leaves, fruit, bark and roots of the plant.  The chemical is toxic to amphibians.  Levels of emodin in the environment are particularly high at leaf out.  This is precisely the time when early-breeding Midwestern amphibian species are active.

This is very practical advice for people who are managing natural areas.  Clearly the first areas that should be cleared of buckthorn are those that may be prime habitat for amphibians.

The research was conducted by Lincoln Park Zoo Reintroduction Biologist Allison Sacerdote-Velat, Ph.D. and Northern Illinois University Professor of Biological Sciences Richard King. The results will be published in upcoming editions of the Journal of Herpetology and Natural Areas Journal.

Imagine what Southern California looked like before European settlement. Accounts in the 1800s indicate that in areas such as Los Angeles wildflowers may have been the dominant vegetation type.

This photo was from an area near Borrego Springs northeast of San Diego in Anza Borrego Desert State Park. If rain comes at the right time, wildflowers bloom prolifically. The wildflowers were one reason why we visited the area this past March.

A new factor, however, threatens these remnant stands of wildflowers in places like Borrego Springs. Sahara mustard, an invasive drought tolerant winter annual, has spread across the desert west.

It has dramatically affected native desert wildflowers including those in the Borrego Springs area. It has turned beautiful fields of wildflowers into a monochrome of green as in the photo at left.

After a rush of growth of Sahara mustard in the Borrego Springs area, community members have faced the loss of another remnant of Southern California’s natural history. Moreover, the loss would not just be one of natural beauty and ecological diversity – the economic repercussions for the Borrego Springs area have already been felt as highlighted in a recent article in the Los Angeles Times.

Fortunately, the Borrego Springs community has refused to concede the fight to the mustard. They formed the Sahara Mustard Weed Eradication Task Force in 2010. With over 30 representatives, the Task

Force is a diverse group of individuals, businesses and governmental entities. Sam Webb is one representative. He and his wife Astrid “retired” in 1998 and moved permanently to Borrego Springs. They were elected honorary mayors of the Chamber of Commerce in 2004-05 and have been active in organizing concerned businesses and have been out in the field beating back the mustard.

Larry Hendrickson on the staff with California State Parks has been working with the Task Force. He has trained “authorized temporary volunteers” who can work within the Park to tackle Sahara

mustard. He has enlisted the help of the National Sierra Club, AmeriCorps, Explorer Scouts. On behalf of the Coalition he has sought assistance from road maintenance authorities to limit the spread along vectors such as highway shoulders and ditches.

When I talked with Larry on our visit to the area in March, he was out working with a Cal Fire inmate crew (low level offenders who typically fight wildfires). Larry says that after eight years of weeding, he has seen less mustard and more native wildflowers in wet years (although he was careful to note this assessment was only based on observations).

As with so many established invasive plants, however, eradication of Sahara mustard is impossible with existing technologies and knowledge. Why, then, keep pushing back against it?

Chris McDonald, Natural Resource Advisor with the University of California, Cooperative Extension says this about the work of the Coalition: “They demonstrate just how beautiful Borrego Springs can be when Sahara mustard is removed and when there is sufficient rainfall. Their work also gives the community a sense of hope that it really is possible to bring back the wildflowers.”

Moreover, stemming the tide – even if just a little – gives researchers (and just as importantly, ecosystems themselves) time to respond. For example, McDonald is doing studies comparing removal methods for Sahara mustard and research on Sahara mustard seeds in the soil seed bank. McDonald has also formed the Sahara Mustard Consortium with a website that provides information on Sahara mustard and links to all sorts of webpages on wildflowers. I especially urge you to read McDonald’s webpage on the natural history of wildflowers in Southern California.

Visit Borrego Springs – regardless whether the wildflowers are blooming!  On our visit, we stayed for about a week. We had a wonderful time! The residents of Borrego Springs are warm and welcoming. We didn’t get to see the sea of blooming wildflowers. (Lack of timely rains depressed blooming of both native annuals and Sahara mustard.) Nonetheless, we enjoyed gorgeous hikes around Borrego Springs. Cacti and perennials were in full bloom, and they were spectacular.

Why do we restore ecosystems? Many of the presentations raised this question at the Midwest-Great Lakes Chapter Meeting at the Ohio Agricultural Research and Development Center in Wooster, Ohio from April 12 to 14. Economics or a sense of duty may motivate us to get out there and restore ecosystems.  Ultimately, I agree with Liam Heneghan from DePaul University who gave a  talk “Ecological Restoration: Scientific, Philosophical, and Sustainability Perspectives: a Chicago Wilderness View.” As he states, ecological restoration can “evoke a love for and allegiance to the places that we live.”

This was a fantastic meeting! Many, many thanks to the 2013 Annual Meeting Committee for their efforts in organizing it: Roger Anderson, David Benson, Hua Chen, Young Choi, Charles Goebel, Jennifer Lyndall, Pamela Rice, Rocky Smiley, Donald Tilton.

There are two early season events for people in the Minneapolis-St. Paul metro area who are interested in learning and taking action against new invasive plants that are showing up in Minnesota.  Both of these program are led by Carole Gernes who is very experienced with invasive plant identification.  I wrote about her and the Invasive Plant Patrol in an earlier post.

INTRODUCTION TO THE INVASIVE PLANT PATROL ADULT

• Thursday, March 21st, 7:00 pm – 8:30 pm
• This program is aimed toward stopping new invasive plants in their tracks!
• Early detection of these plants will allow quick action, preventing more uncontrollable takeovers (like we experienced with buckthorn).
• Learn about new plants causing problems in nearby areas, and how to report them.  Reports are shared via a national invasive species database!
• Ideal for Master Naturalists, Master Gardeners, native plant enthusiasts, older teens and adults wanting to make a difference in their local ecosystems!
• Location: Maplewood Nature Center.
• Call (651) 249-2170 or email MaplewoodNatureCenter to register by March 19.

INVASIVE PLANT PATROL: FIELD TRAINING SESSION FOR MONITORING VOLUNTEERS ADULT

• Friday, April 12th, 6:30 pm – 9:00 pm
• Choose a Maplewood or North St. Paul site to monitor
• Practice using GPS units
• Learn how to identify and report target species.
• Location: Maplewood Nature Center.
• Call (651) 249-2170 or email MaplewoodNatureCenter to register by April 6.

Loss of wild insects, primarily wild bees, decreases

crop harvests.  That is the conclusion of 50 international researchers studying 600 fields in 20 countries. Journal of Science: Wild Pollinators Enhance Fruit Set of Crops Regardless of Honey Bee Abundance  This is a very important finding and is evidence of the link between the domesticated and natural worlds.

Here is a fascinating and related presentation: “Pollinators and Invasive Plants: Implications for Agriculture and Restoration” by Victoria Woicik from the Pollinator Partnership.  Here are a few facts and observations from that presentation: 75% of all flowering plants depend on animal pollinators; 70% of bees nest in the ground; flight is expensive so floral density is important; weediness has been correlated with lower beneficial insect diversity, but stripping a landscape of a flowering invasive may leave a food desert for pollinators.

See also Cornell University Wild Pollinator Research.

About a week ago, I attended the University of Minnesota’s 2013 Legislative Briefing. The briefing was led by President Eric Kaler and was about the University’s request for state funding.  It was packed – over 500 people.

In our state (and everyplace else in the world), scientists and supporters of scientific discovery (I am in the later camp.) need to engage with politicians in supporting their favorite academic institutions. One of the posters handed out to us at the briefing sums up why. It shows a young child lying in a crop field amongst stubble looking through a telescope at the evening sky. She is “illuminated” by a floodlight.  Dark clouds are visible. The caption is “Discovery Illuminates Everyone.”  I like that.

How can supporters of the University become involved? Go to this University webpage: “Be a Light. Support the U.”  (It is not a plea for money but for contacting state legislators.)

How does this relate to invasive plants?  At least two ways:  First, another reason that poster image struck me: off in the distance near a barbed wire fence, there is a plant illuminated by the flood light.  The plant appears to be an invasive thistle!  Second, legislators will more likely put important scientific issues like global warming or invasion biology on their agendas if they know their constituents care about these issues!

Note: I can’t find this image on the web. I will post it when I do.(When I post it, please don’t ask: Why is that child out in the field looking through a telescope on a cloudy night and with the possibility of severe weather?)

After seeing and learning more about the ongoing habitat restoration work at Snail Lake Regional Park just north of St. Paul, Minnesota, I want to tuck my thumbs under my suspenders, stick out my stomach, and beam with a little Minnesota pride. This is a place where a Minnesota Gopher can feel right at home.

The most recent restoration removes invasive tree and shrub from 35 acres of oak woods and shrub swamp along the shores of Grass Lake. During the Fall of 2012, contractors have been cutting and treating buckthorn, Siberian elm, and black locust. As you can see from these photos, they got rid of a big pile of woody invasives!

The woody debris will not go to waste. Evergreen Energy will grind the brush and haul the material to the District Energy biofuel fired heating plant. This plant supplies steam heat for buildings in downtown St. Paul. John Moriarty, Ramsey County Parks Natural Resources Manager says the use of the wood fiber in the heating plant is a more environmentally sound way of brush removal rather than having burn piles in the park.

The oak woods and shrub swamp will receive a prescribed management burn in the spring and then will be have additional wildflower seeds added. Moriarty noted that burning through the woodland area is especially tough in this urban natural area. Wind speed and direction have to be balanced so that the wind is strong enough to push through the woodland without being too strong to blow smoke into nearby neighborhoods.

This project is funded by the Lessard-Sams Outdoor Heritage Council through the Conservation Partners Legacy Grant Program of the Minnesota Department of Natural Resources. The funding ultimately comes from a sales tax that Minnesota voters enacted through an amendment to the Minnesota Constitution. (Yes, voters voted for increased taxes to help the environment!) The amendment raises about $80 million annually for projects like this one.