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When all else fails…

As someone who has had a foot in Horticulture and a foot in Forestry throughout most of my career, people often ask me to compare the two disciplines. One of the truisms that applies in both cases is, “When all else fails, blame the nursery.” I’ve seen this following seedling die-offs in industrial forest plantations and I’ve seen it many, many times after street tree or landscape planting failures. In fact, if you believe some people, tree nurseries are responsible for every plague and pestilence to ever afflict mankind. Are some tree failures related to things that happened in the nursery? Of course. But there are lots of things that can go wrong between a nursery and a tree’s final destination; and even more things that can go wrong after it’s planted.

I know a lot of people don’t believe this, but nursery growers want their trees to survive and grow well after they leave their care. Growing trees is like making cars and any other business. You need satisfied customers if you expect to have repeat business. The best growers are always looking at their production practices for ways to improve their product. Last week I visited Korson’s tree farm in central Michigan. Korson’s grows Christmas trees and B & B landscape conifers. Rex Korson, the owner, has been concerned over the impact of root loss during transplanting of landscape trees. So much so, in fact, that he is conducting his own trial on root pruning.

For those that are not familiar, root pruning of B & B trees is usually done a couple years before harvest by using a tree spade to severe tree roots. The spade used for pruning is slightly smaller than the one used for harvest, so that new roots stimulated by pruning are harvested with the root ball. Does it work? I did a root pruning trial a few years back to see if it could improve survival of fall-planted oaks and had mixed results. For Rex’s trees, however, the initial results were pretty impressive. In the first photo below are root systems of Norway spruce trees dug with a 30” tree spade. The second photo shows the root systems of trees dug with the 30” spade that had been root-pruned last October with a 24” tree spade. The response in one-year’s time was dramatic. At this point there no out-planting data but, other factors being equal, increasing the amount of roots harvested with the tree should increase transplant success.

I should hasten to point out that Rex is not alone. I work with many other growers in the state that are constantly tinkering with this or that in their production systems; sometimes on their own, sometimes with university specialists or extension educators. I’m not so Pollyanna to think that everything is always rosy in the nursery world but most growers, especially the better ones, are aware of the issues out there and are working to build a better tree.

Spruce dug with 30″ spade without root pruning

Norway spruce root-pruned in Oct 2011 with a 24″ spade and dug Oct 2012 with a 30″ spade.

Close up of new fine roots

Tree spade mounted on excavator for root pruning. With this system an operator can root prune 8 trees in 5 minutes.

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Pennsylvania is for…..Snake Oil?

This year at the Philadelphia Flower Show there were a few groups talking about compost tea. Meadow Brook Farm, a farm owned by the Pennsylvania State Horticultural Society is one, and another is F2, a company that provides “Scientific Soil Management”. Apparently they do things that are good for the soil, though the “method” section of their website is a little too vague for me. They also offer pictures of the results they’ve had with compost tea on a few different projects. The one that was most interesting to me was the Rose F. Kennedy Greenway. You can see it here.

Look at the boxwood comparison and you tell me why the compost tea didn’t do a darn thing. Look at the grass comparison while you’re at it.

Throughout the Pennsylvania Horticulture Society’s website there are all kinds of opportunities to find out how to make and use compost tea, including courses at Meadowbrook farm. Now that Elaine Ingham is at the Rodale Institute (Which is in Emmaus Pennsylvania) they have all kinds of classes on it there too. Even Longwood Gardens is Getting into the act (scroll down and click on the compost tea link). So what I want to know is, why have the Compost Tea Gods invaded my home state of Pennsylvania? What makes the keystone state so attractive to people who want to promote snake oil? I just don’t get it. Is it the cheesesteaks? Maybe the scrapple?

No, I’m pretty sure it’s the Rolling Rock….or maybe the Yuengling – America’s oldest brewery (their Black and Tan is one of the best beers in the US – second only to anything brewed by the Surly company). Yeah, that’s gotta be it.

Gone but not forgotten…

Got to spend Friday in the field in northern Michigan visiting growers and seeing some neat stuff: Great fall color, some natural concolor x Fraser fir hybrids and some awesome root systems produced by root pruning. Unfortunately, like the dog that ate the homework, my camera decided not to part with the images. I am tracking down replacements and will post an update on Friday.</d

The wackiness continues

It seems like every year we end up talking about ‘weird’ weather; either it’s extreme heat, extreme cold, too much rain, not enough rain, and on and on. Here in the upper Midwest and other parts of the central US, however, 2012 is clearly a year to remember. Our winter was fairly unremarkable until we hit 8 days over 75 deg. in mid-March. This pushed our growing degree days up at least 3 weeks and set the stage for widespread late-freeze damage in April, wiping out the state’s cherry, peach, and plum crops. Summer turned out warm and dry, highlighted by record-setting heat in July.

Weekly average high temperatures from MSU Hort Farm weather station: 2012 versus average of 15 previous years.

Now that we’ve seen some relief from summer’s drought and heat, we’re experiencing one more weather-related phenomenon: stress flowering. At my place I had lilacs and azaleas start to flower in August. We have also had reports of crabapples flowering in the eastern part of the state. Trolling around the web, I ran across a photo of magnolias blooming this month in Kansas City.

Magnolia flowering in mid-September. Source: Kansas City Star

So, what’s going on? Severe heat and drought can cause plants to go into a state of eco-dormancy. Typically we define “true” dormancy as a state where plants won’t grow, even when environmental conditions are favorable. Eco-dormancy represent the flip-side; plants should be growing but can’t due to severe environmental stress. In some cases the stress can induce flowering, such as we’ve seen this year. We have also seen examples of trees that have re-flushed, sending our new leaves after shedding leaves during the peak of the drought.

Will any of this cause long-term problems for trees and shrubs? Probably not. Stress flowing tends to be sporadic so most flower buds on a tree or shrub are likely to be unaffected. Shoots that re-flush late in the summer may or may not be able to harden off before winter. If not, they will be subject to freeze injury just like shoots that flushed earlier the spring. The main concern for 2012 is the cumulative toll of our environmental extremes.

Why I Don’t Worry Too Much About Organic Fruits and Veggies

Let me tell you something you already know. If you grow something in your own garden you’ll know exactly what poisons were or weren’t put on it, how much fertilizer was used, and furthermore it will taste better.

If you buy your apples from the guy down the street who you’ve known for 20 years you’ll be able to ask him what he used to grow the crop, why he used it, and you’ll have the satisfaction of supporting a local industry. And yes, those apples will taste better than grocery store apples.

If you go to a farmers market you’ll be able to ask the people there exactly what they did to their crops, and why they did what they did. And you’ll feel good about supporting the local economy. And yes, the food will taste better than anything from the grocery store.

If you walk into a grocery store or Target, or Kmart or whatever and pull a fruit or vegetable off the shelf which has the USDA Organic Label on it and say to yourself “Hey, I’m doing something good for my family and the environment” then, in my opinion, you’re fooling yourself.

There, I said it. I believe that, AS USDA ORGANIC CERTIFICATION NOW EXISTS, the USDA Certified Organic label does not provide a significant indicator that the fruit or veggies you’re buying provide a significant benefit in terms of human or environmental health. Please note that I’m not saying anything different than our government does – what they say is: “Organic is a labeling term that indicates that the food or other agricultural product has been produced through approved methods that integrate cultural, biological, and mechanical practices that foster cycling of resources, promote ecological balance, and conserve biodiversity.”

Notice that they never say that organic is superior to conventional production, simply that organic uses practices that “foster cycling of resources, promote ecological balance, and conserve biodiversity”. Though many of you may not believe it, conventional growing uses many of these practices too – producers know that if they don’t pay at least some attention to sustainability then they will lose money over time.

So why am I talking about this today? Well, I’ve had a few requests to discuss that new meta-study that came out a few weeks ago which showed that organic food has the same nutritional value as food produced conventionally. Big deal. Plenty of other meta studies have shown essentially the same thing –the quality of organic is LARGELY the same as conventional with a few nutrients (often vitamin C) a little higher in organic and a few (often protein levels) being higher in conventional. Anyway, to make a long story short, I don’t know why this study got more press – maybe they have better PR people at Stanford where the study was put together.

Look, the reason that one food has more nutrients than another has much more to do with the food itself than whether the food was grown organically or conventionally. No matter how you treat a McIntosh apple, it will never have as much vitamin C as a Granny Smith apple. Period. Folic acid will always be greater in bananas than grapes. Period. If you’re worried about getting enough of a particular nutrient then eat foods high in that nutrient. If you’re worried about a lot of nutrients then eat a varied diet.

Of course the study also says that synthetic pesticides are more likely to be on conventionally produced foods than organically produced foods. OK, I’ll buy that. Makes perfect sense….but tell me, how much organic pesticide is on organically produced foods? And how does it affect you? If a farmer uses spinosad, an insecticide used by organic growers, it can be present at low levels in food, as can other organic pesticides such as pyrethrum. But since residues of these organic pesticides are rarely tested you have no idea how much is in there.

Look, if you want to avoid pesticides on your fruits and veggies altogether and can’t grow a garden or go to a farmer’s market, then you should avoid foods where pesticides need to be used. These are the only foods where you can count on growers, organic or conventional, avoiding pesticides (No farmer WANTS to use pesticides – they’re expensive!). To find foods where pesticides are less likely to be used just go to that crazy dirty dozen list which the Environmental Working Group puts out (which I think is a bit ridiculous – but I’ll leave that alone for now since this post is getting long) and select fruits and veggies from the clean 15.

In terms of organic production being better for the environment, as long as organic growers can use copper to control diseases, I’m concerned about how long term applications of this copper will affect
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soils on land devoted to organic production over the long term. I’m also concerned about fertilizer runoff and leaching in organic production – same as in conventional production. Nitrogen and phosphorus from manure can and do run off just the same as nitrogen and phosphorus from synthetic fertilizer.

In both conventional and organic systems, the impact that production has on the environment comes down to the responsibility that a given producer takes for doing the right thing and protecting the environment. To say otherwise is just silly. There is so much leeway in the USDA organic system that there is plenty of opportunity for a USDA organic producer to do things that will make their operation significantly worse for the environment than a conventional producer of the same crops.

The new hardiness map’s obsolete! The new hardiness map’s obsolete!

I posted back in January about my excitement about the update of the USDA Hardiness zone map. While I acknowledged some of the shortcomings of the new map, I was excited because it was a big improvement over the old map, both in terms of content (more recent temperature data included) and presentation (interactive search features, better graphics).

Dr. Nir Krakauer, assistant professor of civil engineering in The City College of New York’s Grove School of Engineering, was less impressed, however, and has essentially declared the new hardiness map dead on arrival. Dr. Krakauer conducted his own analysis of climatic data and determined that much of the country is already a half zone to one full zone warmer than the new USDA map. Why the difference? The USDA zone estimates were based on a simple average of annual minimum temperatures from the past thirty years. Dr. Krakuar’s applied a regression analysis to account for more recent warming. One of the key observations of the new analysis is that winter minimum temperatures are warming much faster than average temperatures, leading to the new hardiness zone projections.

So, what do we do with this information? All of the limitations that we associate with hardiness ratings still apply. Most landscapes experience micro-climates that may be slightly colder or warmer than the surrounding area. Plus, winter hardiness is just one piece of information in plant selection (we also need to also consider sun exposure, pest pressure, soil factors – drainage, soil pH, and so on). Most importantly, average temperatures don’t kill plants, extreme temperatures do. So whether we look at long-term averages or try to account for the most recent trends; the extreme 1 year in 5 or 1 year in 10 is what will cause issues. For example, if Krakuar’s projection is right and we’re a zone warmer on average, then the greater Lansing area is now zone 6b (0 to -5 deg. F). We’ve been colder than that in 2 out of the last 4 years.

The press release that accompanies Dr. Krakuar’s study starts with an attention-getting line: “Gardeners and landscapers may want to rethink their fall tree plantings.” But really things haven’t changed that much from the past. How homeowners and landscapers use zone information is still a matter of risk tolerance. If I chose a zone 5 plant and we’ve really warmed to zone 6, I’ve lost nothing. If I gamble and plant zone 6 plants and we drop back down to -10 or -15 deg. I may be looking for replacements. And, of course, there’s the tendency of many gardeners to ‘push their zone’, so we may have folks trying to grow zone 7 plants in Lansing. Which is fine – as long as people understand the risk. Actually I think a better approach to hardiness zones may be a probability rating: Are you willing to take a 1 in 10 chance your plant won’t make it? 1 in 4? 50-50? As new climate data are added to the model, garden centers could post and update the odds, sort of like the latest line at a sports book in Vegas. Those that want the ‘tried and true’ can stick with the old zone 5’s; those that want to live on the edge can pay their money and take their chances.

The good, the bad, and the ugly. A reply.

Ginny Stibolt of the Florida Native Plant Society recently posted Native Plant Issues: The good, the bad and the ugly, featuring me as the ugly. I posted a reply on her post, which I include here. To keep things in context, I encourage you to read her post first.

Enjoy your weekend!

Hi Ginny:

Some comments and a few points of clarification.

On the first item, as a Federal agency the USDA is bound by the Executive Order on Invasive Species which defines natives as species that occur in an ecosystem “other than as a result of an introduction”. I suspect they tried to simplify the language for the National Planting day release when they substituted ‘naturally occurring’.

On the Arbor Day Foundation, I am fairly certain they use contract nurseries in various locations for their tree sales. In any event, they have plenty of trained foresters on their staff that understand the importance of provenance and they would not send trees from northern seed sources to Florida or vice versa. But I certainly can’t fault the idea of supporting the Arbor Foundation, declining their trees, and buying trees from a local nursery.

On the Google + Hangout discussion no one was ‘booted off’. These were straight and simple technical issues. If people watch the Youtube video, the audio sounds like Neil Armstrong on the moon. This is a new technology for most of us and we are dealing with some growing pains. I would have much preferred even numbers on each side. Having an imbalanced debate can work against the majority, too. As Wilt Chamberlain famously observed, “Nobody roots for Goliath.” That said, we did have a lively and cordial debate and I hope people will bear with the grainy images and tinny audio and take a look.

Kentucky coffeetree

I haven’t watched the video but I don’t think I said there were no natives that could be used as street trees here in Michigan. If I did, I misspoke. That might be true for Linda in the Northwest – if you look at the native tree list for King county you’d be hard pressed to find anything that could be recommended in good conscience as a street tree. We have a few more options here in Michigan. If we were looking for a street tree for Lansing or Detroit the list could include hackberry, honeylocust, Kentucky coffeetree, tulip poplar, swamp white oak, and red maple. But even this list makes urban foresters cringe because they think red maples are already over-planted, tulip poplar is weak-wooded, and hackberry is difficult to transplant. With regards to Mary Wilson’s comments, there is a distinction between street trees and landscape trees. Landscape trees could be anywhere on a residential or commercial landscape where they could receive irrigation or other care so there is broader list, in contrast to street trees found on street sides in tree lawns or tree pits. Street trees are subject to the ‘worst of the worst’ in terms of environmental conditions; minimal rooting volume, compacted soils, road salt, and reflected heat load; but they provided the ‘biggest bang’ in ecosystem services, especially cooling buildings and sidewalks.

Swamp white oak

This has been an interesting discussion and clearly I have touched a nerve. I have to confess I have never been vilified so much in my life, which has been a little discomforting but also strangely flattering. When I met with Jeff and Linda earlier this week Jeff commented, “Wow, I’ve never been able to sit across the table from the devil incarnate before!” Fortunately, I work in academia where we spend most of our days telling one another how stupid the other is. People that seek to avoid criticism generally don’t do well in this line of work. Peer review forces us to critically examine our statements and sharpen our arguments. I was pleased and gratified to see some of the changes proposed for FNPS website and literature – why leave ‘low hanging fruit’ around for critics? While I didn’t appreciate some the comments made about me, if I’ve caused this group and others to strengthen their arguments and re-examine some of their assertions regarding natives, then the slings and arrows I’ve taken these past couple weeks haven’t been in vain.

Poisoned bird seed and trust

Over the years I’ve said some nice things about Scotts Miracle-gro products, such as one of their potting soils, and some not so nice things, such as with their Round-up resistant Kentucky bluegrass. I’ve never thought of them as a particularly good or particularly bad company, just a company trying to do the best it could while being reasonably honest about what it was doing (You could argue that they tried to pull something fancy with the Round-up resistant Kentucky bluegrass, but I’m going to give them the benefit of the doubt and say they were just exploiting an obvious governments loophole – not exactly good, but hey, it’s a dog eat dog world out there).

But then the news broke that they had applied insecticides illegally to their wild bird food products, falsified pesticide regulation documents, distributed pesticides with misleading and unapproved labels and distributed unregistered pesticides. If you haven’t seen the article yet you need to look here.

Damn.

Anyone who has read much of what I write knows that I try to tell the truth about products to the best of my ability, to do this I rely on a lot of different sources of information, including information provided by the company itself. I trust that, for the most part, companies try to do what they say they’re doing (or not doing) in terms of letting us know what’s in their products. At the least I assume that they follow the government’s rules and regulations.

This is a serious breach of my trust.

How am I supposed to deliver the facts about Scotts Miracle-Gro products when I can’t trust them to do what they say they’re doing?

I mean really? How can I talk about their products again? I have no idea what’s in there.

I’m trying to think of something pithy to say next – but I’ve got nothing. I’m deeply disturbed that this could happen, and, at least for the time being, I just can’t, in good conscience, trust this company or its products. Sure, the company is saying all the right things now, but that’s not enough.

Here’s a thought – maybe they could publicly state that they’re not going to release the Round-up resistant Kentucky bluegrass – you know – to prove that they really are serious about avoiding doing things that might disturb the environment. And then actually do it. Yes – that would be a good start.

Wandering in the Woods

This past week a friend of mine, Carol Reese, an Extension Specialist at the University of Tennessee (and one of my favorite speakers), told me that she’d like to post a little something about natives. I said sure, no problem, just send it along. And she did. But before posting it sometime next week, I thought I’d post another article that she sent along — one that isn’t quite so sciency and which will let you get to know Carol before you hear what she has to say about natives.

As a side note — Carol was bitten by a copperhead in the foot this past year — had to be given 10 units of anti-venom. From what she’s told me she has recovered to almost 100%.

Wandering in the Woods

by Carol Reese

Every morning at dawn, my dog Junebug jumps on the bed and approaches my sleeping form. My eyes slit open to see her just inches away, staring intently at my face. The instant we meet eyes, she bounds happily off the bed and runs around the bedroom, loudly rousting the rest of the dogs, who thump their tails, stretch, yawn, and come to the edge of the bed to see if Junebug is telling the truth about me being awake. I’m allowed one quick cup of microwave coffee, though the flapping of the dog door drives me crazy as they run in and out staring at me impatiently. Why they won’t go on without me isn’t fully understood, but for some reason, they want their slow two footed friend to go, too.

I live on an old farm, and though it’s not mine, I feel as though I’m kin to this land. I am, I guess, since, if I were to fall and molder into this ground, my flesh would be recycled into the plants and the animals that feed on them. That thought makes me comfortable most anywhere, but here, there’s more to make me feel at home. Old farms like this have a lingering sense of long-gone eras and of the people who lived here before. The old Ford Jubilee tractor still sits in an outbuilding, looking identical to the one on the farm in Mississippi where I was raised. Predating that, is a large horse collar hanging in the old barn. The kinfolks tell me it was worn by a Percheron, used for pulling logs from the woods. I imagine the old days, the big horse comfortable in the rolling green pasture, woods for shade, and a lake for drinking.

The dogs and I are drenched by dew these spring mornings. The woodland phlox are almost finished blooming along the edge of the woods, and the bearded tongue (Penstemon) is just beginning to peak. Wild azaleas and dogwood were blooming earlier, but now it’s the bell-like clusters of the tree huckleberry, the tallest member of the blueberry family. The many native ferns are hitting their glory days, and along a sunny creek bank, I come across American wisteria (Wisteria frutescens) and a native clematis (Clematis crispa) This clematis will have wiry blue hanging blooms with four pointed petals that curl back like a rolled up hat brim. Further, in a sunny field, I find oxeye daisies and coreopsis. Though the milkweed and butterfly weed is not blooming yet, I see two monarchs cartwheel among them. Looks like butterfly hanky panky to me, and I will look
here later in the summer for the bold striped monarch caterpillars that feed on those species..

Grinch, my little schnauzer mix, suddenly arches high up off the ground and comes down with both front paws in perfect diving form. Dirt sprays as she digs ferociously at the ground where a mole made the earth bulge. Nearby, I notice several clumps of foliage that were covered with little light pink striped flowers earlier this spring. It’s Claytonia virginica, or spring beauty. With a sharp stick, I pry up the tuber beneath the foliage. It’s one of the wild foods that I find pretty good, either raw or cooked, tasting to me like a cross between water chestnut and boiled peanut. (My brother says they taste like dirt to him!) The dogs assume I must know something they don’t, like the whereabouts of the mole, so they jostle up next to me, ears pricked. A couple of them are willing to help me dig, but don’t take offense when I refuse the offer. I get a pocket full
and we ramble on to more important business. There’s a blue grosbeak nest I’m keeping free of cow bird eggs.

The dogs’ tails sink with disappointment when I turn back, except for the old ones, who have taken to plodding along behind me instead of ranging as they did in years past. One day I’ll have to bury them and let their bodies enrich the meadows they so enjoyed exploring. Another day in the future, some other person will walk this farm and rediscover the pleasures in these fields. It’s a kind of immortality, isn’t it?

Fearless fall color predictions

Happy Labor Day! Hopefully everyone had an enjoyable 3-day weekend. Labor day is the unofficial end of summer, which means fall is just around the corner. In fact, fall may be a little early this year around these parts. We are already starting to pick up some fall color – mainly maples, sassafras, and sumac. I usually get some calls from various media outlets asking for predictions on fall color. It’s always a dicey proposition. Weather going into fall is certainly a factor for fall color, but conditions during the fall itself are the final trump card. As I noted, we’re likely to see an early fall here in the Upper Midwest and, if we don’t start getting some decent rain, I suspect it could be a relatively short season as trees begin to drop leaves early due to continuing drought stress. Of course, all this can change relatively quickly if we get into a different weather pattern.

July 28, 2012. Sumac in fall color near DeWitt, MI.

Speaking of fall leaf color, the Fall Color Guy (aka Dr. Howard Neufeld, Appalachian State Department of Biology) has started his annual reports. http://biology.appstate.edu/fall-colors . This site is a great resource if you’re planning on doing some leaf peeping in the Appalachians. And even if you aren’t, I still recommend this site as one of the best on the biology of leaf color.