December 2012 – The Garden Professors™

Happy New Year

As trite as it sounds, I try to slow down and enjoy the simple things around the holidays. We are starting to get some more seasonal weather, which means cold temperatures and occasional snow flurries. Once we get our first real snow cover I pull out my birdfeeder from beneath the shop-bench in the garage, fill it up and set it in a beech tree outside our kitchen window. No one in our family is a birder but it’s interesting to see how nearly everyone takes time to linger over their morning coffee or tea to watch the steady parade of chickadees, nuthatches, cardinals, and jays at the feeder. The feeder itself has some sentimental meaning as well. I bought it at an auction for the Arboriculture Society of Michigan meeting several years ago and it was handmade by Dan Kurkowski, longtime city forester for Detroit. Dan was a tireless tree advocate for the Motor city who passed away, much too young, six years ago but I always remember his passion for people and trees. And every time I set out the feeder he built I remember how he closed every e-mail with the line for the Lorax, “I speak for the trees for they have no tongues.”

I hope everyone enjoys a quiet and restful end of their holiday season.

Final Exam of 2012?

Actually, just a pop quiz.

Continuing the "flowers that look like Christmas ornaments" bit as started on our Facebook page…here’s another, as seen a couple of days ago in our visit to the conservatory at the Biltmore Estate, Ashevegas, N.C.

You can probably guess the family by the leaf shape.

Nice dangly peduncle, no?

Let’s have some guesses, temperate-zone readers! This had me stumped, and I’m not unfamiliar with tropicals. And yes, I want one.

(Zone 9-10 west-coasters: please sit on your hands for a bit, then you can tell us how common it is and "I pull this weedy thing out of my garden by the handful." Ha!!!)

An Interesting Video

Every once in a while someone sends us a news story or a video to look at critically. A couple of days ago Michael got in contact with us through Facebook and asked us to take a look at a video he saw recently and let him know what we thought of it. This video was posted on Russ Bianchi’s website (he goes by the name Uncle Russ). He includes a short note with the video which says “ALL Genetically Modified Organisms, Ingredients, Crops, Livestock, Food, Drugs, Cosmetics, Beverages, Packaging, Flavors, Fragrances, Colors! Soaps and Detergents are UNSFAE AT0ANY EXPSURE LEVEL and are proven to cause cancers, disease and premature DEATH”. Wow. All that from a video? Must be a heck of a video.

Here’s the video.

As far as I can tell, The party responsible for this video is Media Roots which is defined as “a citizen journalism project that reports the news from outside of party lines while providing a collaborative forum for conscious citizens, artists and activists to unite.” Too bad they didn’t include scientists who know something about genetically modified crops. According to Youtube this video has been viewed over 250,000 times.

I can’t tell you exactly what the other garden professors think of it (it may not be printable), but from my end, much of this video is absolute hogwash.

But, having said that much of this video is hogwash, I must give credit where credit is due. The first part of the film which explains how genes are moved from one organism to another was, in my opinion, pretty well done. Sure, there were parts of it that a serious molecular biologist would complain about, but for the average person I thought it was a nice explanation. In fact, after seeing this first part of the film I was expecting to see some really serious and thoughtful critiques of genetically modified organisms – because there absolutely are some good critiques of genetically modified organisms out there. Unfortunately I was sorely disappointed. Let me go through the major problems that this video raised one by one and explain why they’re faulty arguments (I won’t go through all the problems, just the major ones):

Genetically Modified crops show lower yields – Yes, this is sometimes true, genetically modified crops aren’t genetically modified to produce more, just to resist certain pests that might reduce yields (or resist certain herbicides that help control pests). So the maximum yield for genetically modified and non-modified crops are usually pretty similar if the farmer growing the non-genetically modified crop controls pests with pesticides, or doesn’t see the pest for some reason.
Genetically Modified crops have poisons in them – Yes, this is sometimes true. Genetically modified crops may have genes from Bacillus thuringiensis in them (In the video this name was misspelled and the species was capitalized – which is a big deal to a scientist). What the video didn’t mention is that this is an organic pesticide that has been used for years with, as far as we can tell, no adverse effects to humans. The report about people being hurt in the Philippines is a complete red herring. This supposedly occurred in 2003 and all of the data that we have points to a problem besides GMO corn pollen – in fact, the data points to a flu outbreak. This conclusion is strengthened by the fact that GMO corn pollen hasn’t been implicated in a similar incident since then.
Genetically Modified Insulin is bad! – This one does have a grain of truth. GMO insulin is cheap and available, which is why it is used. In the vast majority of patients there appears to be no difference between it and naturally acquired insulin. But it does seem as though some people do have a negative reaction. It terms of deaths, I can’t find much that is trustworthy to corroborate what was said on the video.

I have been chastised previously for being pro-pesticide, pro-GMO, pro-Monsanto, etc. I don’t blame people for saying this because, let’s face it, I do end up defending these things sometimes because their opponents often use bad science. But saying that I’m for these things is going a little far. There is good science and information out there that calls into question the value of certain pesticides, GMOs, and even Monsanto. Look up the new genetically modified Kentucky bluegrass that may be coming out soon. Look up atrazine. Look up how Monsanto protects its patents. These are things I’m opposed to. Another thing I’m opposed to is saying that something is bad without having a good understanding of it. If you’re going to make a video that 250,000 people watch then do your homework and get as much of it right as you can.

Buried alive – the roots version

Bert’s post yesterday inspired me to share one of my own timelines that I followed for 7 years. As many of you know, I am a proponent of bare-rooting container and B&B shrubs and trees. One of the benefits is that you can prune away malformed roots, but another is that you can ensure the roots come into contact with the native soil as soon as possible. It’s interesting to see what happens over time with the more typical “pop and drop” method.

I saw this rhododendron being planted in 2002. If you look closely, you can see that it was originally balled and burlapped – the burlap is up around the multiple trunks. Then the burlapped bag was put inside a contained filled with media. You can see that, too. So a hole was dug that exactly mirrored the plastic container and the whole works was lifted out and plugged in.

Visualize a giant jawbreaker with different colored layers. At the center, we have the roots surrounded by clay. This is encased in burlap and twine. Then there’s a layer of container media. And finally we have the native soil. Rather than making it easy for this rhododendron to get established, we now have several barriers for new roots to overcome.

The primary problem here is all of the different textures of stuff in this planting hole: clay, soilless media, and native soil. Water doesn’t move easily through different soil types (remember Jeff’s demo on drainage?) and if water doesn’t move, neither will the roots. And as you follow this time line, it becomes quite apparent that the roots never established into the native soil. Look in particular at the size of the leaves (they are markedly smaller as time goes on – a great indicator of chronic drought stress). The line in the masonry wall makes it easy to see changes in height – or lack thereof.

Installed in 2002 (year 0)

Early 2004 (Year 2)

Late 2005 (Year 3)

Early 2007 (Year 5)

Note the leaf necrosis from chronic drought stress. Having a ground cover competing for water does not help. And neither does pruning off dead parts of leaves.

Now unfortunately I was not able to make it back again until 2009. And here is what I found:

Why oh why? (Buried alive version)

Sometimes when I’m stumped for ideas for blog posts, I get in my car and drive around my neighborhood. Usually within 10 or 15 minutes I’ll see something stupid enough to write about. Today was no exception. We live in a mostly rural area north of East Lansing but development is slowly but surely encroaching around us. Part of that development includes a couple of golf courses. One of the golf courses recently announced they were going to develop a high-end RV park adjacent to their course. If you’re like me, ‘high-end’ and ‘RV park’ don’t sound like they belong together in the same sentence but I’ll take their word for it. In any event, when the project was announced the developers placated local residents by noting they would install a large berm around the RV park to screen it off from two highly traveled roads next to the park. Said berm was installed about a month ago.

Anyone see anything wrong with this picture? There are about a dozen trees in similar straights. Doesn’t give me much faith in the rest of this project…

I think the one on the right will be OK (it’s a telephone pole). The one on the left, not so much…

“Quit yer bitchin’. Ya wanted a berm, we built ya a dawgone berm!”

Planting Edibles in Cities

The snow has just started falling and I’m already thinking about what I’m going to be planting next spring. Most of my plantings won’t be at my own house, they’ll be out in the cities of St. Paul and Minneapolis. We’ll be looking at all kinds of fun stuff like growing trees in various new types of containers, adding compost to planting holes in different circumstances, and even pruning methods. But one of the big things that we’re starting to look at are new trees for the urban environment. Cities have always spent time considering what they plant, but with the emerald ash borer ravaging the Midwest, now they’re thinking even harder. And because of the local food movement, suddenly the cities are at least considering trees like apples and hazelnuts on a trial basis (sure, there are some places that use them here and there, but they’re less than common). Of course, if this movement stalls, the cities would be upset at having so many “messy” plants around (that’s their big concern about edibles right now), but I don’t think it will. I’m actually pretty optimistic about using fruits and nuts on public property. Sure, some plants will fail because they get too many diseases or insects, or because they’re weak wooded, but some will make it too. I think hazelnut has a great chance in the right place (it would be too bushy for most boulevards….). Do any of you have a favorite edible that you think might work well in a city? Let me know, maybe we’ll try it!

Closing the loop

Just a short post today as I am participating in an Extension planning meeting for most of the day. One up-side to the meeting is we are meeting and having lunch at Brody Dining hall here at MSU. If you’re around my age and attended college in the 80’s, the thought of eating at a dormitory dining hall might elicit memories of a hair-netted cafeteria lady glopping amorphous slop on your tray next to the mystery meat of the day. Boy, how times have changed. Today, the quality of dining hall food is point of competition for universities angling for students. The Brody dining center is set up like a food court, daily choices for students include a fresh salad bar, southwest food, sushi, made to order pizza, home-style comfort food, even kosher food.

The dining halls are also part of MSU’s sustainability initiative. Food wastes from the dining halls are collected and sent to an anaerobic digester and composted at the MSU Student Organic Farm. The compost is used at the recently completed Bailey hoop-houses on campus to produce salad green and herbs for use in the dining halls, providing a closed-loop system. Is the food produced in the hoop-houses going to make the dining halls completely self-sufficient? Probably not in the foreseeable future. But they do provide a good opportunity to promote horticulture. The project has generated numerous press articles and there are posters around the dining hall highlighting the project. In an age when many bemoan the public’s disconnect between farm and fork, the Bailey GREENhouses remind students, especially those that might not think about it otherwise, where their food comes from.

The eternal [gardening] optimist

I’ve gotten better, actually. After slaying hundreds of dollars worth of mail-order and/or inappropriate plants, I’ve learned to curb my urges a bit.

But not this time.

I was overcome by a sale at “Annies Annuals and Perennials” – the most decadent, irresistible, West Coast, Zone 9 catalog ever.

Behold! The impossible-to-grow and majestic Puya*

Mine! Mine! Mine!
It will reside in my greenhouse over the winter.

Packing peanut left in pot for scale.

Now taking bets as to how many years ’till bloom. Side action on years/months until I kill it.

*Can one of you familiar with the genus inform me as to pronunciation? I’m pretty sure my current “rhymes with booyah” isn’t it.

The secret of immortality

Last Sunday’s New York Times had a story about immortal jellyfish. It was interesting, and given my previous life as a marine biologist, it was also a topic that was comfortably familiar. But really, I wasn’t that impressed. Because plants do the same thing, yet no one bats an eye.

Gardeners and other plant aficionados have exploited the plant kingdom’s ability to remain forever young. How many of us have taken cuttings of mature plants, rooted them, and started new ones? I have a couple of miniature African violets whose leaves I can place on damp soil in pots, cover, and ignore. New plantlets emerge from the base within a few weeks. I pot these up and give them away as gifts, but always keep a few for later propagation.

Some of the horticultural oddities we love exist because of plant immortality. The Camperdown elm (Ulmus glabra ‘Camperdownii’) has been perpetuated for almost 200 years from a single original cutting from a tree in Scotland. Particularly pernicious weeds do this on their own thanks to runners and rhizomes. Sure, we call it “vegetative propagation,” but really, it’s plant immortality.

So you’ll have to forgive me for not getting all torqued about immortal jellyfish. I’ve seen immortality, and it’s growing in my garden.

Does fertilization increase insect herbivores?

Always fun when you find a research paper that confirms what you’ve suspected all along. I ran across a paper last week in the Annals of Applied Biology entitled ‘Fertilisers and insect herbivores: a meta-analysis’ (Butler et al. 2012. Ann Appl Biol 161: 223–233). I’m interested in the topic because in recent years a dogma has emerged that if you fertilize a landscape tree it will be immediately devoured by insects. In this study the authors conducted a meta-analysis (basically a compilation of studies on a given topic and then combining and analyzing the aggregated results) and looked at dozens of studies of the response of insect herbivores to fertilization to answer the question, does fertilization increase insect damage? The answer was absolutely no surprise to me: It depends.

What does it depend on? First, what type of insect. Secondly, what kind of fertilizer. For example, fertilizing with nitrogen greatly increases populations of sucking insects. This makes sense when you stop to think that aphids and other sucking insects have to consume a lot of phloem sap –which is essentially sugar water – in order to get sufficient nutrients. Nitrogen fertilization did not significantly increase populations of chewing insects, however. This could be related to off-setting effects of improved nutritional quality of leaves versus increased presence of defense compounds or leaf toughness. For other fertilizer elements Butler et al. found that phosphorus decreased insect populations in 2/3^rd of the studies (14 out of 21) and that potassium decreased insects in 7 out of 10 cases. As with nitrogen only, complete fertilizers (NPK) tended to increase insect populations, especially for sucking insects.

I should hasten to point out some limitations of the study as it relates to tree fertilization. First, of course, is the British spelling of fertilizer. Second, the study mainly dealt with fertilization in agronomic crops, not trees. Lastly, the authors only included studies on insect adults. In many cases insect larvae, not adults, are the most damaging life stage, especially for insects that affect trees. Nevertheless, the study highlights the difficulty of making generalizations when discussing host stress and insect interactions. In addition to type of insect and type of fertilizer, we could have added nutritional status of the plant before fertilization to the ‘It depends’ list. My rule of thumb is that trees shouldn’t be fertilized unless a problems is noted by visible symptoms, a soil test, and/or a foliar test – and preferably by more than one of these.

Bottom line: Before you buy into the notion that fertilizing a tree is going to increase insect problems make sure you know what type of pest you’re dealing with, what type of fertilizer and the current nutrient status of the tree.