Demonstrating Diversity

As I noted a few posts back, this summer marks the 10th anniversary of the discovery of emerald ash borer (EAB) in southeast Michigan.  While a lot of progress has been made on many fronts in the battle against EAB, the outlook for ash trees in North America still looks bleak for the foreseeable future.  Ash trees, both green and white ash, were popular choices as street and landscape trees throughout the Midwest and elsewhere.  In Michigan ashes comprised up to 30% of the overall tree cover in some communities.  Like chestnut blight and Dutch elm disease, EAB provides a cautionary tale of the destructive potential of invasive pests.  As global trade continues to increase (and the potential for exotic pest movement along with it), the most practical defense in the near term is to spread the risk and increase species diversity.  In spring 2003 Bob Schutzki and I installed an ash alternative species demonstration at the MSU Tollgate Extension Center in Novi, MI, near the epicenter of the EAB infestation.  As we near the completion of the 10th growing season of the planting we can take stock of some of the better selections.

Dana (R) and Aniko assess the lindens

Hophornbeam Ostrya virginiana

Hardy rubber tree Eucomia ulmoides

Northern pine oak Quercus ellipsoidalis (R) can maintain good leaf color even when soil pH turns Q. palustris (L) chlorotic.

American Sentry linden Tilia americana ‘McKSentry’

Baumannii horsechestnut Aesculus hippocastanum ‘Baumannii’

State street maple Acer miyabei ‘Morton’

Thanks to our partners!

I’m Burnin, I’m Burnin, I’m Burnin For You! — A Short Story Told With Pictures

To those of you who don’t like Blue Oyster Cult, I’m sorry, I just couldn’t stop myself.

A couple of weeks ago I mentioned that I spend some time flame weeding.  It’s a technique for getting rid of weeds by frying them using a 500,000 BTU (I’m not kidding – that’s how powerful this thing is rated) torch hooked up to a propane tank.  It’s not something I do a lot, just something that I get the urge to do periodically — when I need to feel macho.

Here’s the blow by blow – it’s kind of a good news, bad news story.


a Good news – Igniting the propane torch was quick and straightforward process.  The torch lit on the first try!


Bad news – Here’s my hairless finger after igniting the torch.  Even though the process of igniting the torch was quick and easy, I still burned all of the hair off of the fingers on my right hand. The black dots are all that’s left of my fantastic finger fuzz.


Good news – Damn but I feel powerful using this thing!  It’s like holding a jet engine in your hands!  Yes, it does make me feel macho.


More good news – only a couple of days later the plot looks almost spotless!


Bad news – Two weeks later the perennial weeds are already on their way back.  The ground insulates the roots too well.

Suddenly Symphyotrichum

Also the Anemone x hybrida, Solidago, etc.  Everything’s blooming early here in the Mid-Atlantic.

"Fall-Blooming Anemone." Not.

I teach an herbaceous plant i.d. and use course each fall and spring. By looking back at my plant lists, I can tell what was blooming when.  I usually teach the asters at the end of September.

That’s going to be tough this year, since they are all BLOOMING RIGHT NOW dammit.   This will be a great experiment in "does deadheading = rebloom" for many of the asters.  Things like garden phlox (Phlox paniculata) are dependable post-deadheading rebloomers, but I can’t say I’ve ever  needed to deadhead Asters to get another flush of blooms, since they bloom right before frost for us, then pffftttt anyway.

Great Fanny’s Aster, this is too early! (Sympyotrichum oblongifolium ‘Fanny’)

My source for perennial maintenance advice is Tracy DiSabato-Aust’s marvelous "The Well-Tended Perennial Garden."  I’ve utilized her strategies for cutting back to both delay blooms and create a more compact plant.  If I’d been thinking ahead (ha, ha!), a good whacking on some of these things might have fended off blooms for another month or so; or at least had something to look at when class starts at the end of August. But alas. At this point the best I can hope for is a sporadic bloom or two.  At least I have lots of photos for lecture…

Making hay while the sun shines

If you live anywhere east of Montana you know that two-thirds of the country has been roasting under record heat for the past few weeks.  While the weather has been a bane to farmers and many others, it has provided us with an ideal set of conditions to begin to look at the responses in the SoMeDedTREES project. 

To recap, we installed two experiments with 25-gallon container-grown ‘Bloodgood’ planetrees.  In both experiments we applied one of three treatments to the root systems at planting: 1) “Shaved” the outer  portion of the root system to remove  circling roots, 2) “Teased” apart the outer portion of the rootball to remove circling roots and 3) “Control” where we did nothing to the root system, or “Pop and drop” to use Linda’s terminology.  One set of 48 trees was planted at the MSU Beaumont Nursery where half the trees were fertilized (400 g of Osmocote 15-9-12) and half were not.   The second set of trees was installed at the MSU Hort Farm.  At this site I made an executive decision to change the Fertilizer treatment to a Mulch comparison based on our discussions related to a recent study that suggested mulching does not actually reduce evaporation or improve soil moisture. We applied 3” of ground red pine bark in a ring approximately 40” in diameter around each tree in the “Mulch” treatment and left the other half of the trees with bare ground.

Overview of SoMeDedTREEs site at MSU Hort farm

If I had a hammer…  Summer Intern Aniko Gaal demonstrates proper form for installing TDR rods in clay soil (also works for relieving frustrations with your choice of summer employment).

Obviously this is a long-term study and we’re a long ways from any definitive results – especially with regard to the impact of the root treatments on eventual root structure – but the point of this exercise is to allow GP blog readers to come along for the ride and get a glimpse of what goes into our research.  For the mulch study one of our primary objectives is to track changes in soil moisture and tree stress associated with mulching.   In order to monitor soil moisture we are using a technique called Time Domain Reflectometry or TDR for short.  A TDR system is basically a glorified coaxial cable tester.  The system sends out an electrical pulse to a set of metal rods that are buried in the soil and then measures the return signal.  The greater the moisture in the soil, the longer it takes for the signal to return.  The instrument converts this information into volumetric soil moisture (% volume water/volume soil).  For this study we installed rods at two depths 15 cm (6”) and 45 (18”). Rods were installed 12” from the trunk of the tree at the edge of the root ball (inside) and 24” from the trunk of the tree (outside).

Volumetric soil moisture at 15 cm and 45 cm depth of planetrees with and without mulch at MSU Hort farm, Summer 2012.

We planted the trees in mid-May and watered them from a portable water tank once a week until mid-June.   Since then we’ve left the trees on their own.   So far the trees actually seem to be fairing pretty well given the heat.  We have one tree that is beginning to drop a few leaves but most look pretty good.  Our soil moisture readings to date are consistent with a couple of related studies that we’ve done that show mulching increases soil moisture.  Soil moisture was greater at the 45 cm depth than at 15 cm and the difference between mulch and no mulch was greater at the shallow depth.  Still very early, obviously, but we will continue to update – sort of like FOX Radio news: “We report – you decide.”

The ugly side of compost

In my part of the world we’re able to send most of our organic stuff through the green cycling program, where it ends up being made into compost.  Cedar Grove contracts with the City of Seattle to do this service.  As you might imagine, this requires huge, multiple facilities to handle all of the organic material that comes through the system.  And it’s not difficult to imagine that problems arise, especially in choosing locations for these sites.

I don’t know anyone who would welcome a large composting facility next to their neighborhood, and I sympathize with people who were living downwind of where these facilities were constructed.  (People who moved there afterwards should have known what they were getting into.)  But even worse is putting a facility in an environmentally sensitive area – like on an island.

On one hand, it might seem the perfect solution – put the facility on an uninhabited island to keep mainland neighbors happy.  On the other hand, it’s an ISLAND – runoff is going to be a problem.  So if such a site is chosen, then the company should be required to manage runoff and keep it out of the water.

Thus, I was most severely vexed to hear that Cedar Grove has asked to be exempted from the rules regulating phosphorus runoff into the adjacent slough. Unlimited amounts of phosphorus.  The facility routinely exceeds the legal limit of runoff of phosphorus and occasionally other nutrients set by the state Department of Ecology. Citations, fines, and out of court settlements are nothing new to this company.

According to their spokesperson, Cedar Grove "cannot find a treatment that would work" to manage phosphorus pollution and need a waiver from the requirements. Somehow this has become the public’s problem and we should just absolve Cedar Grove of any responsibility to be a good environmental steward.  

I don’t know what bugs me more: the fact that this corporation did not design an adequate facility to contain the runoff before it began operations, or that whatever governmental agency approved their plan didn’t require it.

Shut ’em down.

A rose by any other name…

Many blue spruce trees in our area are suffering from a progressive decline.  This is more than the usual combination cytospora canker & rhizospaera needlecast that tend to make most mature blue spruce look crappy.   The current syndrome has been linked to phomopsis blight and affected trees show increasing branch die-back and in some cases trees go from a having a few dead branches to completely dead in a 3-4 years.  Because of this alarming and pervasive issue, I’ve been asked to put together a list of alternative selections for blue spruce as part of my extension duties.

Whenever I put together one of these lists I always include my all-time favorite conifer; a graceful, elegant tree that is native to the Pacific Northwest but grows well in Michigan and fulfills a range functions in the landscape.  Of course that tree is… well, that’s the problem.  I’m not sure what to call it anymore.  In Mr. Chance’s 6th period Botany class at Olympia High School 30-some years ago I learned it as Alaska yellow cedar, Chamaecyparis nootkatensis.  Had to get the Latin spelling right to get full credit.  When I moved to Michigan in 1999 I heard people talk about Alaska cypress or Nootka cypress.  Took me a minute but I figured it out.  At least I could take comfort in the scientific name.  After all, as Mr. Chance taught us, we use scientific names to eliminate confusion; using Latin since it is ‘dead’ language and not subject to change.

About the same time I came to MSU a new conifer was discovered in Vietnam.  The new tree, Vietnamese golden cypress, was originally described as Xanthocyparis vietnamensis.  Moreover, this new species was closely related to nootkatensis, so both were added to the new genus.  Subsequently it was argued that the genus Callitropsis was originally used for Xanthocyparis nootkatensis before it became Chamaecyparis.  So, based on precedent Callitropsis was the proper genus for nootkatensis and vietnamesis.  Got it?  Well, as Lee Corso would say, Not so fast my friend…   Here’s the rest of story from the font of all knowledge, Wikipedia:

‘In 2010, Mao et al. performed a more detailed molecular analysis and placed Nootka Cypress back to Cupressus. However, this is disputed, as the tree would compose a monophyletic subgenus. "The argument that it warrants treatment as a monotypic genus is not without merit, in which case the correct name is Callitropsis nootkatensis."’

Then the Wikipedia poster shows their true colors.

‘Although acceptance of the revised classification of this tree is widespread among botanists, inertia in the horticultural and forestry industries (both typically very slow to adopt the results of botanical research), mean the name Chamaecyparis nootkatensis is likely to continue being listed in many situations.’

So let me get this straight.   Taxonomists have put the tree in four different genera within ten years and in one sentence current molecular analysis puts the tree in Cupressus (which the International Botanic Congress approved last year) but that’s disputed by other botanists – and WE’RE the idiots because we won’t jump on board?!