Steward – Nov ’14 Real Dirt

Contents (click a title or scroll)

Roofs Alive! Green (Vegetated) Rooftops for Northwest Michigan

Invasive Ornamentals—Tricky Choices

Healthy Forests – Healthy Communities, Today and Tomorrow


Green Roof by Inhabitect LLC

Green Roof by Inhabitect LLC

Roofs Alive! Green (Vegetated) Rooftops for Northwest Michigan

MGANM Meeting, October 7th 2014

Whitney Miller

Nathan Griswold of Inhabitect, LLC spoke to us about vegetated (green) roofs. He began with a small history of the usage of green roofs, including this tidbit: the hanging gardens of Babylon were the first recorded green roofs. Nathan’s background in the industry includes working on the World Trade Centers Memorial gardens, the PepsiCo building in Chicago, was one of 100 profeesionals that reviewed the Green Roof Policy for Washington D.C. and much, much more.

What exactly IS a green/vegetated roof?

Green roofs come in all shapes and sizes, and can be anywhere from 3” deep to 3’ deep. They can include all types of things, including a running track!

Essentially they include a non-permeable waterproofing layer, topped with an underlayment, drainage materials, and topped lightweight soil. Many factors go in to a green roof: the load capacity of your structure, the intent of the project, depth requirement of the soil for desired plants, architectural regulations, engineering regulations, and the list goes on. Before considering a green roof, ensure that you are working with a qualified professional who is well versed in all of this.

A green roof is more than just a pretty thing to look at. There are numerous benefits.

  • Social benefits: Job creation, urban food production, reduce urban food deserts, educational opportunities, aesthetics improvement, improve health and well being of all involved.
  • Economic benefits: increase property value, increase tax value for your city, and decrease municipal costs. There are many major cities that are now offering tax breaks to put in a green roof. For instance, Washington D.C. will give you up to $10 per square foot!
  • Environmental benefits: Manage storm water more effectively, sound attenuation, increase wildlife habitat, reduce urban heat island effect.

What kind of maintenance do they require?

Maintenance of a green roof all depends on how you want the roof to look. If you want a natural/undeveloped/wild look, you will have less maintenance as far as the plants go. Inhabitect can install irrigation on the roof as well, and they can maintain the roof for you if you want. For the most part, established green roof need maintenance about once a month in order to ensure that all drainage areas are free of debris and it is functioning as designed. The amount of time for the plants is the same that you would spend on them down on the ground (grade level).

What do they cost?

The average homeowner that is interested in installing a green/vegetated roof can expect the cost to be somewhere in the beginning ballpark of $30 per square foot including the waterproofing layer. Of course, prices are subject to change based on cost of materials as well as the intensity of the project.

Are there any green roofs around northwest Lower Michigan?

YES! Cherry Capital Foods just installed one on their new headquarters; the new condos being developed in downtown Traverse City (near the Post Office) will have a green roof; The condos on Cass/8th are building a shed with a green roof in Bellaire this month; Headlands Dark Sky Park (Mackinaw, MI) is building a $7+ million dollar observatory with a green roof (and will be designed to keep the light pollution to near zero); the new Suttons Bay market place will also have a green roof.

Inhabitect LLC will be offering “Do It Yourself” kits in early 2015. The kits will include construction plans as well as the lumber, waterproofing and other required components. Nathan plans to offer a range of options. Sizes may include things such as sheds, and he will even be offering some plans for chicken coops!

If you would like to see the listing of plants that are often well suited for use in a green roof, the materials that Nathan kindly provided for us will be kept inside the MGANM cabinet in the BRNC classroom (where we keep the coffee). Please note that these items belong to MGANM, so make sure to leave them for the next person. And as always, you can follow the link to Nathan’s business to learn more about this subject and get help to get your new green roof project started.


photo courtesty of Monika Chandler, Minn. Dept of Ag; shared by

photo courtesty of Monika Chandler, Minn. Dept of Ag; shared by

Invasive Ornamentals—Tricky Choices

Katie Grzesiak, Invasive Species Coordinator with the Northwest Michigan Invasive Species Network

One of the hardest parts of gardening is selecting plants. Which would look best? Which will flourish? There are so many fantastic options to choose from, sometimes narrowing the selection becomes harder than choosing a plant you like. Whether it helps you eliminate choices from an endless list, or adds another layer of complexity, please consider how these plants interact with our natural areas when making your selection.

Though only 10 introduced species (out of 100) become established outside of cultivation, and only one of those becomes invasive, about half of the most serious invasive plants arrived by way of our gardens. Some are an obvious problem, even in landscapes, but others, like Japanese barberry, don’t spread much in yards. Their seeds are carried farther away by birds, allowing populations to crop up in local natural areas. These populations out-compete native plants, removing food resources for native creatures (from caterpillars to deer). Even the native plants that are able to compete with invasives face more grazing “pressure” from native herbivores, as many invasive plants are unpalatable.

Invasive ornamental plants come in every shape and size. The highest-priority invasiveplants in northwest Michigan are the plants that have been very invasive in similar areas (like the Northeast US), but aren’t well established here yet. This includes plants like blue lyme grass, Japanese barberry, baby’s breath, Oriental bittersweet, black and pale swallow-worts, and Japanese knotweed (sometimes called “Michigan bamboo” or similar names). If you have these plants (or their cultivars) in your landscape, please work to remove them immediately! It is presently illegal to sell or trade Japanese knotweed and a few other plants in Michigan; it is not illegal to have them in your garden, but please remove them to keep them from spreading to our high-quality natural areas (even when you don’t see it in your yard).

Other invasive ornamentals may be more commonly used, spread slower, or may only spread vegetatively (and not by seed). These plants are lower-priority in northwest Michigan, but if it works in your plan for your garden to remove them and replace them with other plants, please do so! This list includes plants such as Norway maple, snow-on-the-mountain, burning bush, forget-me-nots, and periwinkle. These plants still take up valuable space and resources that could be used for native plants that fit into our habitats better. Lower-priority invasive plants are an “ecological dead zone,” even if they aren’t spreading aggressively.

As you’re removing plants, consider replacing them with native alternatives. Our native plants provide habitat for birds, bees, and butterflies, and are beautiful and hardy to boot. Garden professionals participating in the Go Beyond Beauty program have vowed not to sell high-priority invasive plants, and many offer native alternatives; consider rewarding this bold move with your business, and encourage other professionals in your area to join this program!

For lists of invasive ornamental plants and native alternatives, to learn more about Go Beyond Beauty and the Northwest Michigan Invasive Species Network, and to find ways to get involved, check out our website,,or contact Katie at or (231) 941-0960 x29.


Classical symptoms of oak wilt on red oak leaves. Note drying and tanning of leaf from tips and margins to base. photo by: Dr. David L Robert, MSU College of Ag & Natural Resources

Healthy Forests – Healthy Communities, Today and Tomorrow

Kama Ross, District Forester, Benzie, Leelanau and Grand Traverse Counties

Being a wise and active steward of our Northern Michigan forests is as important now as ever before. Effective stewards manage their forests for today while preserving benefits for future generations. A greater percentage of my days serving landowners in Benzie, Leelanau and Grand Traverse Counties is spent dealing with insect and disease concerns – far more time than when I graduated from college over 30 years ago. Our growing global connections bring many new, non-native insects and diseases that require us to be more observant and pro-active if we want to sustain our forest resources in a healthy and vigorous condition. Following are some of the most prevalent forest health issues that I talk about with area landowners every day.

Emerald Ash Borer – We are still experiencing the effects of this exotic beetle that had its start in Southeast Michigan in 2002. Experts predict that 99% of the white, black and green ash in Michigan will succumb. That is not likely ‘news’ to anyone reading this newsletter. If you still have ash trees that do not have dieback in the top one-third of the canopy, epicormic branching (sprouts from the trunk or the roots), splitting bark, D-shaped exit holes, and woodpecker damage, then perhaps your tree can be successfully treated. Research suggests that insecticide treatments may be able to save infested trees exhibiting low to moderate dieback (20 to 40 percent). Drenching with an insecticide every spring, or having a tree service professional inject larger diameter trees, has been quite effective. My husband and I have drenched a mature ash in our front yard for 5 years and so far so good! Here is a link to a helpful EAB treatment bulletin.

If your trees are more than 40% dead or you have a forest of dead/dying ash, the wood is still good to use but it is very difficult to find someone that will not charge you to cut and remove. Ash is very nice firewood and we do still encourage landowners to harvest and utilize on site whenever possible. The woodpeckers and nuthatches that feed on the borer are the winners in this one!

Beech Bark Disease (BBD) – If you have seen something that looks like snow covering the bark of our beautiful beech trees, then you are seeing the protective coating surrounding the beech scale, a tiny non-native insect boring into the living tissue of the tree. Thousands of little holes are now providing an entry for Nectria fungi to enter and invade. Cankers form and disrupt the tree’s conducting capabilities. Beech then decline and often “snap” which is simply catastrophic structural failure of the tree’s main stem. Beech snap is very hard to predict and around homes and recreational areas, it has become a serious management dilemma. BBD was first detected in Michigan in the Ludington area in the early 2000s. Scientists have initiated research trials to try to manage the disease, including insecticidal sprays and oils and scrubbing the bark in attempts to dislodge the scale. Again, on select, high value trees around your home – treatments may make sense, but in a forest situation, it is just doesn’t work nor is it affordable. These tiny scale insects are wind disseminated. A good source of management information can be found HERE. Again, early detection and treatment is crucial to save these wonderful trees in your yard.

Oak Wilt – I’m spending at least a part of every day, visiting landowners in all three counties with serious outbreaks of oak wilt. This summer, Leelanau County was added to the list with a confirmed outbreak just down from my home. Oak wilt is an exotic disease that poses a serious threat to Michigan’s red oak trees. The fungus plugs the water-conducting system of oak trees. Oak wilt is fatal for the red oak family but thankfully, white oak experiences only branch dieback. Infected trees die quickly, often within a few weeks of the appearance of symptoms. The disease, which occurs across much of the state in both urban and forest settings, moves rapidly to healthy oak trees through root systems that have grafted with diseased trees. While oak wilt-infected trees cannot be saved, healthy trees can be protected by breaking root grafts before the disease can spread. A 5-foot-long steel blade mounted on a vibratory plow is used to sever the root systems below ground. Red oak trees growing inside the treatment lines are then cut and chipped, burned or sawed into lumber to help prevent overland spread of the disease. Leaving diseased trees standing increases the risk of overland spread by beetles that can move oak wilt spores long distances to healthy trees. So, you can imagine, it is very difficult and expensive to control new outbreaks. Educating landowners on minimizing the possible spread is our best defense. Not removing or pruning red oak from April through August will help, waiting to remove infected trees until fall, properly removing infected wood and sharing your information with neighbors in oak areas is recommended. Here is a help page.

Just to keep us all on our toes (if we aren’t depressed and exhausted already!), foresters have serious concerns about another invasive – the Asian Longhorned Beetle. Many infestations have occurred on both coasts, but most troubling is some recent news that an infestation in Toronto was deemed “eradicated” only to have another beetle siting that erases a lot of hard work. This beetle has a list of 20 plus trees that it will feed on, but top on its preferred list is maple! Also extremely troubling is an infestation in Southern Ohio that resource professionals are struggling to control and the fact that a load of campfire wood with beetle eggs, larva or adults is all it would take to bring this devastating insect to Michigan. Be on the lookout for pencil-sized holes in the trunk of a maple, very large, scary beetles! Here is a reference page.

Being a good forest steward means walking your woods, observing changes, seeking professional advice and making decisions that increase the diversity and overall health of the trees around you. As the District Forester for the Conservation Districts in Benzie, Leelanau and Grand Traverse Counties, I provide on-site assistance at no charge ( Let’s walk your woods together and talk trees!

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