17 Sep

GLA Working to Eliminate Yellow Iris

Education, News No Response

At left, yellow iris sites on Fisher Lake.

The invasive species yellow iris has spread in the watershed over the past several seasons and the GLA is asking riparians for their help in eradicating the plants. Property owners have been notified and are part of the solution to combat the spread. A group of nine NMC Freshwater Studies Program students are currently working with our GLA interns, assisting with identification, mapping and removal.

The work is focusing on the Fisher Lakes, but plants also can be found on the north and east shores of Big Glen and along the Crystal River. The removal project this season is expected to continue through the first week of October.


Native to Europe, Northern Asia, the Middle East and northern Africa, the yellow iris (Iris pseudacorus) most likely made it’s way to our shores as an ornamental plant. Many landscapers, pond designers and home gardeners choose to include it in their designs for it’s beautiful yellow flowers in bloom from mid June to mid July. It is lovely, in bloom, but problems arise when the seed pods mature, arch over the water, split open and disperse. It can travel far and wide on the waters of our lake, washing into crevices, lodging against berms and taking root. Over time it can create a dense mass, choking out the diversity of native plants that keeps our shores looking like northern Michigan and that keep our local ecosystem healthy.


Observed increasing over last several years by our watershed scientist Rob Karner and invasive plant specialist Laurel Voran. Laurel has been aware of this plant’s agressive nature from her work in the horticultural field and from the experiences of others in our region and nationwide. One person who has been involved with controlling this plant around Portage Lake described his experience like a game of “whack-a-mole” : “At first there were just a few, and then we found it popping up here, there and everywhere!”



This year we have taken efforts to carefully identify and document where yellow iris has taken root. We have done surveys by boat, by foot and by drone to assist in documenting as many current infestation sites as possible using mapping software.

We have removed the seed pods of any plants that flowered this summer to prevent further spread via water currents. (the seedpod stems arch down and can release into the water – spreading far and wide.)

Small infestations have been removed by digging. We are in the process of contacting affected landowners and determining best methods to destroy larger populations.

What you can do:

  • 1: Contact us immediately if you know you have yellow iris and have not already heard from us. Remove any existing seed pods, or give us permission to do so.
  • 2: Pay attention to any iris on your shoreline and let us know if any have yellow blooms next summer.
  • 3: Ideally: Work with us in removing any yellow iris from your shoreline. Minimally: remove and destroy seedpods from yellow iris plants you desire to keep.
  • 4: Do not purchase any yellow iris to plant anywhere on your property. (And- Be aware that yellow iris and our native blue blooming iris (Iris virginica and/or Iris versicolor) are confused in the trade. You may intend to purchase either of the natives, but it may reveal itself to be the yellow iris upon bloom.)
  • 5: If you find this Iris for sale at nurseries or garden centers, ask them to stop selling it.
  • 6: Donate to the GLA to support terrestrial invasive species efforts to help us cover the costs of erradicating it.
  • 7: Educate your friends and neighbors about the threats of this plants, in spite of it’s beauty.

Learn more by watching these informative videos on the subject.

Eradicating Yellow Iris and Purple Loostrife

Digging Out Yellow Iris

03 Sep

Understanding Overlay Districts

Education, News No Response

Steep slopes map

Every watershed should have a variety of tools to protect the water. Education is one of the biggest and most effective tools but effective zoning can pay big dividends as well.

Using a zoning Overlay District (OD), as defined by the boundaries of the Glen Lake/ Crystal River Watershed, is an excellent way to plan for the long-term protection of our water. If the OD does its job, it will be the gift that keeps on giving.

Keep in mind that existing development within the OD would be exempt from the new provisions. The OD would however provide guidance for future development and changes to existing development. Either way, every watershed resident should become educated on the OD to understand its implication for water protection within the context of reasonable development.

Click here to learn more about the “Overlay District” on the GLA website.

17 Aug

Glen Lake Association Celebrates 75 years, Rob Karner Recognized for 40 Years of Service

Education, News No Response

Clear skies and the 80-degree temperatures of a perfect summer afternoon didn’t keep more than 100 people from turning out for the GLA Annual meeting this August. The commitment of this organization’s members has not waivered for more than 75 years now.

Meeting participants were treated to two special videos; the first highlighting the history of the GLA, current programs and a vision for its future, (watch it here); and the second congratulatory messages from longtime community partners in watershed protection (see who they are). Additional acknowledgements from Senators Stabenow and Peters and State Senator VanderWall, State Representative O’Malley, Lt. Governor Gilchrist and Gov. Gretchen Whitmer were also shared, thanking the GLA for 75 years of service to Leelanau County.

Another historic milestone recognized during the meeting and acknowledged by elected officials was 40 years of service by Watershed Scientist, Rob Karner. Since 1979 Rob has built an outstanding curriculum vitae of science-based initiatives that have vaulted the association to recognition as one of the premier lake organizations in the Midwest … and one closely followed and often imitated by groups countrywide.

The many contributions of tireless volunteers and generous donors were also acknowledged including special thanks to the Greg and Sue Besio family. Their $100,000 gift to the popular Discovery Boat Program will help ensure this popular educational program created by Rob Karner will continue into the future. The Discovery Boat Cruises virtual or live are one of the best opportunities for the GLA to educate and share critical preservation information. They are just one more example of Rob’s relentless desire to share his knowledge with so many.

The State of the Watershed address by Rob Karner was comprehensive as always and generated great questions. A few highlights include the Watershed Protection Plan Update, a proposed Watershed Protection Overlay District and Swimmer’s Itch prevention. Slides from Rob’s presentation can be viewed here; video coming soon!

The business portion of the meeting included a solid finance report from outgoing treasurer David Herr (read it here). All three outgoing board members, Dale DeJager, Bill Witler and David Herr were thanked for the donation of their time for their wise counsel during their time on the board. Numbers from elections included 178 votes cast online and 15 proxy votes received resulting in election of all three highly qualified board candidates. Dave Cheney, Kris Fishman and Jennifer St Julian were welcomed onboard.

A message of thanks was delivered to outgoing president Dave Hayes, the GLA “won the trifecta” under his leadership by completing the first ever GLA Strategic Plan, implementing a new communication software, and adapting staff roles to better poise the GLA to meet the organizational and educational challenges ahead. A final message of gratitude for all our volunteers and encouragement to get involved was shared by Dave. Check out the full recording here.

13 Aug

Engineered Seawalls – Are They Appropriate for Glen Lake?

Education, News No Response


The 2017 GLA shoreline survey revealed that Glen Lake had a total of 18 engineered seawalls (made of wood, steel, or concrete), with seven seawalls located on Little Glen and 11 on Big Glen.
A subsequent 2019 shoreline survey showed a reduction in numbers; Glen Lake had a total of 15 engineered seawalls – a reduction of three. Four were on Little Glen and 11 were on Big Glen. In 2019, we had six wooden seawalls, six steel seawalls, and three made with concrete.

Why the reduction in seawalls? One reason they did not increase is because they are very expensive. Second, when installed, the wave energy is transferred to the neighboring shore, causing unwanted erosion on that shore.

The average size of an engineered seawall is 100 feet long, resulting in a total of 1,500 feet of shoreline with these man-made structures. Glen Lake has a total of 17 miles of shoreline and less than 2% of our shoreline has engineered seawalls.

GLA acknowledges that installing an engineered seawall may be warranted in extreme and unusual situations. Typically, engineered seawalls are used on the Great Lakes where erosion forces are more intense and destructive. Smaller inland lakes typically have much less erosion forces and may utilize rocks or coir logs as the better “lake friendly” choice for erosion protection.  

GLA is encouraged by the news that there has been a reduction of seawalls on Glen Lake. It is a step in the right direction to protecting our watershed from further erosion problems.

If you wish to remove your engineered seawall with an appropriate erosion control strategy, please contact the GLA at for guidance or call 231-334-7645.

It should be noted that all shoreline alterations require a permit from the Michigan Department of Environment, Great Lakes, and Energy (EGLE), formerly the Michigan Department of Environmental Quality.

For more information about the negative impact of seawalls on water quality for inland lakes, click here.

03 Aug

GLA’s Annual Meeting is Thursday, August 6

Education, News No Response

The Glen Lake Association Annual Meeting will be held on
Thursday, August 6, from 4 pm to 5:15 pm 

Please join us online!

Registration is required to attend the Zoom webinar which will feature:

  • A new 75th GLA video
  • Special recognitions
  • State of the Watershed address with watershed biologist, Rob Karner.

Register here.

20 Jul

Road End Permitted Uses

Education, News No Response

The Glen Lake Association (GLA) has been dedicated to protecting, preserving and caring for the Glen Lake/Crystal River Watershed for over 75 years. Through scientific research, invasive species control and education the GLA strives to protect the environment and quality of life for all users of our waters.

In an effort to limit invasive species from entering our waters, the GLA monitors the 17 road ends that exit on both the Glen Lakes. While the GLA does not have the ability to legally enforce actions at the road ends, we do acknowledge the importance of adhering to Michigan Inland Lakes law for the protection of our lakes.

Below we have identified key resources for road end information and rules. You may also
contact the GLA office at or call (231)334-7645 with further

Public Act 56 of 2012 makes it a misdemeanor to use public road-ends for placing boat hoists or
boat anchorage systems, mooring or docking boats between midnight and sunrise as well as installing a dock or wharf. The penalty is a $500 fine, with each 24-hour period constituting a
separate and new violation, thus allowing for subsequent and repeated citations. The Road-
Ends Law also creates an implied cause of action in the civil courts as well.

Permissible activities are limited to accessing the surface of the water and the installation of a
public dock to assist in providing access to the water. Other recreational activities, such as
those normally conducted at public parks like games and sunbathing, are prohibited, including
the anchoring of boats and other watercraft on a non-temporary basis.

Empire Township:
Select Ordinances-Road End Ordinance

Glen Arbor Township:
Select #1-2008 Public Road Endings 11.18.08

Empire and Glen Arbor Townships: Zoning Administrator Tim Cypher 231-360-2557.

Michigan Lakes & Streams (search Road-Ends)

22 Jun

New Discoveries in Swimmer’s Itch

Education, News No Response

Prevention is the Key

“An ounce of prevention is worth a pound of cure” so the saying goes.  This certainly rings true for Swimmer’s Itch. Prevention is the key to itch free enjoyment of our waters.

Listed below are suggested preventative strategies based on GLA Swimmer’s Itch research on the behavior and life cycle of Swimmer’s Itch. If carefully employed, these methods will work to greatly reduce the total number of or even eliminate itch cases for an entire swim season. Please note that these strategies should be used together to be most effective at preventing Swimmer’s Itch.

  • Cover your skin with swimwear that covers the area you want to be itch free (SI rarely affects a person’s hands, feet, and face)
  • Towel off vigorously after swimming
  • Swim in the afternoon or early evening vs. morning
  • Do not swim when the wind is blowing onshore.
  • Do not swim/wade in shallow water without using prevention measures
  • Install a swim baffle in your swim area (two years of research indicates this works!)
  • Use a parasite skimmer (watch the video link below for more info)
  • Use a kid friendly wading or “kiddy pool” vs. using shoreline lake water for small kids to swim more safely and itch free.

Be aware that there is never a case, even using all these tactics, that Swimmer’s Itch risk can be reduced to zero. But there is so much we can do to have our best chance at preventing the itch. Check out this informative Swimmer’s Itch Prevention Video on what we learned from our 2017-2019 research and for more details about what you can do! And if you do experience Swimmer’s Itch, please click here to report a caseWith your help, we can monitor and track cases of Swimmer’s Itch —and progress in managing it.

Brief tutorial and history of Swimmer’s Itch

Cercarial larva is the parasite that causes Swimmer’s Itch on Glen Lake. (NOTE: there are multiple species of parasites that cause Swimmer’s Itch in Michigan.) Cercariae are shed by multiple snail species that are infected by parasites transmitted by avian hosts —such as the Common Merganser, Canada Geese and Mallard ducks.

Historically we tried to break the lifecycle of the parasite in one of the two hosts. We tried to kill the snails by copper sulfate treatment, but that was ineffective (snails repopulated after expiration of the two hours of chemical potency). However, this was the only treatment for more than 30 years, from the 1950s to the 1980s. We tried to remove and harass the resident mergansers which at the time were thought to be the exclusive avian hosts on our lake from the 1980’s-2019. Despite these efforts, numbers of mergansers and cases of swimmer’s itch increased, and we discovered through DNA testing that mergansers were not the exclusive SI hosts we had once thought them to be.

Where are we now?

The Glen Lake Association has a 30-plus year effort in the research and management of Swimmer’s Itch. Our research in the mid-’80s helped define the life-cycle of Swimmer’s Itch on Glen Lake, i.e., one snail species and one bird species. Research from 2017-2019 again revolutionized the scientific understanding of Swimmer’s Itch. Through use of DNA testing, multiple species of itch were identified (including a never before discovered species) cycling through multiple bird hosts in addition to the Common Merganser, all contributing to Swimmer’s Itch on Glen Lake. Given what we now know, it is clear that attempts to control Swimmer’s Itch by interrupting this complex life cycle are ineffective.

Given the newly understood, increasingly complex nature of Swimmer’s Itch and clear and overwhelming evidence that copper sulfate application and Merganser harassment, trapping and relocation are ineffective and even harmful, what is there left to do? The Glen Lake Association has learned and continues to make new discoveries that lead us to new approaches for combatting Swimmer’s Itch. The key to future success in our treatment of Swimmer’s Itch is to prevent humans from coming into contact with the Cercarial larva. Using what we have learned about the behavior of Swimmer’s Itch, we can arm our ourselves against exposure to the Itch.


Prevention is the key! Research has demonstrated that there are methods and technologies available to effectively control individual swimmer exposure to Swimmer’s Itch. But we need your help! Ongoing research including the use of data from Swimmer’s Itch case reporting will be keys to furthering our ability to protect against and prevent Swimmer’s Itch.

Watch an informative video about SI here.



18 Jun

75th Celebration Fundraising Campaign: Supporting our Watershed Scientist Position

Education, News No Response

It’s all about the water….

After 75 years, the Glen Lake Association is celebrating this impressive milestone with the same basic focus: protecting and preserving the water within the Glen Lake/ Crystal River Watershed.

To commemorate this accomplishment with an eye to the future, the GLA Board of Directors is announcing the “75th Celebration Campaign” now underway.

Contributions raised between now and our Annual Meeting date of August 6 will finance GLA’s Watershed Scientist position, currently held by Watershed Biologist Rob Karner.

The association’s 75th Campaign goal: $150,000. Please click here to donate. 

Thanks to the generosity of three investors, the 75th Campaign has been challenged to raise $75,000 which they will match dollar-for-dollar, doubling the impact of every gift.

“Over seven decades of caring about our water by many people has brought us to where we are today,” said GLA development chair, Lori Lyman. “Through sound management practices, cutting-edge research and support by boards, staff, and a long list of volunteers committed to saving this resource, GLA is known throughout the state and beyond. Despite this strong leadership and progressive programming, the challenges continue with more invasive species, increased pressure and use and changing environmental conditions. To save this cherished water, GLA needs to remain vigilant in its research and education efforts.”

Please help us by investing in the future of the GLA during this landmark year. Your support will enable GLA to continue to research and deploy environmental best practices resulting in protecting and preserving the unparalleled Glen Lake/ Crystal River Watershed.

08 Jun

New Discoveries in Swimmer’s Itch

Education, News No Response

It has been widely accepted by many Swimmer’s Itch scientists that once Common Mergansers (once thought to be the major player in Swimmer’s Itch on Glen Lake) were live trapped and ready for relocation, that the approved DNR relocation sites were “safe” places to set the trapped birds free. The Michigan Department of Natural Resources (DNR) approved relocation sites based on four principles:  

  • New area is not a good swim area;
  • Site is free of the snail species that carries the parasite that cycles through Common Mergansers;
  • Not a place where the DNR fisheries were planting fish;
  • Suitable for Common Merganser survival

The 2019 Swimmer’s Itch research has now confirmed that many of the relocation sites have been tested “positive” for the species of parasite that cycles through Common Mergansers! This is bad news for the Swimmer’s Itch control program because it likely means that relocating Glen Lake mergansers to relocation sites that already have the parasite will only increase—perhaps dramatically—the itch risk for swimmers near the relocation sites. This new discovery presents a new ethical dilemma for the GLA and other lake associations around the state that use live trapping strategies.

One would think that a simple solution to this dilemma would be to find new sites that meet the DNR criteria where the parasite is not present. This may be a solution, but in the opinion of the local experts, there are likely “no new sites” to be found. Also, new discoveries have shown that relocated mergansers travel up to 20 miles once they are set free. 

Old Assumptions, New Thinking

Just a few years ago, it was thought that almost all of itch-causing worms came from Common Mergansers, with other birds like Mallards and Canada Geese only minor contributors. It was standard thinking, therefore, to assume that removing Common Mergansers from Glen Lake would have a major impact on reducing itch risk.  

However, 2019’s research on Swimmer’s Itch shows that Mallards and Canada Geese contribute to the parasite load in percentages higher than imagined. The mix of Swimmer’s Itch parasites from all the birds collectively contributes to increasing itch risk.

New data also suggests that snail densities, which can directly impact itch risk, fluctuate significantly from year to year. For example, when certain species of snail densities are high and combined with high population densities of the bird host, then SI risk for that specific life cycle can be problematic in a given year and move to center stage while other life cycles either hold their own or diminish.  

What does this mean for Glen Lake and our lake-wide effort to control Swimmer’s Itch? One thing is certain, the life cycle that is dominant one year may play a minor role in the next year, depending on snail density fluctuations and changing bird populations. This is a complex issue, with Mother Nature throwing in all kinds of twists and turns that make lake-wide control not only difficult but perhaps unattainable.

GLA will continually update you with new information as we receive it.

04 Jun

GLA Pioneering New Study on Septics, Seeks Riparian Volunteers

Education, News No Response

The GLA has engaged Freshwater Solutions, LLC and the University of Alberta Canada to conduct a pioneering study on septic influences on our surface waters (lake) and drinking water (private drinking wells). 

Ordinarily, the county health department and/or the National Park Service is involved in monitoring public beaches on Glen Lake for E.coli and will close down beaches if E.coli exceeds safe levels for swimming. As in the same way with drinking water, the county health department is primarily responsible for testing home drinking wells, with the tests including E.coli, nitrates and other parameters.  



So why is GLA getting into research that health departments normally cover?  

The reason is centered around the advent of new technology that the health departments are not yet equipped to handle. The new technology involves quantitative polymerase chain reaction, or qPCR. With this new technology, we can detect and quantify the DNA of enteric bacteria that comes exclusively from septic systems.  

Our goal this summer is to choose 15 willing riparians on the shores of Big and Little Glen and test for enteric bacteria in the drinking water and the surface waters along the beach. There will be three sampling dates for each site. Samples will be taken during June, July, and August. If you are interested in gaining some peace of mind and are willing to be a part of this study, please contact Rob Karner, GLA’s watershed biologist, at his email:  

We will also combine water samples with septic drain field analysis and evaluation using drone technology and infrared cameras. We hope to be able to determine if drain field failure is detectable using thermal imagery.

If you are interested in being a part of this study, please contact us soon. There are limited spaces available for this unique, in-depth opportunity. Those who are selected to participate will be asked to contribute $250 each, to offset the total project cost of $8,900. For the cost of a regular septic inspection ($250) you could learn much more about your system and support the Glen Lake Association in conducting important research.

Note: Results of the study will be shared with the membership in a statistical manner that protects the privacy of individual participants. Individual results from each of the sampling sites will only be shared with each respective property owner in a confidential manner.

We look forward to your individual interest in this important study. Remember, failed septic systems are one of the leading causes of water quality degradation.  

Watch this video for more information on septic and well water protections: Road Map of Enteric Studies video.