Uncategorized – Page 46 – The Garden Professors™

Happy Holidays!

Relaxing at the in-laws in Ohio for the long Christmas weekend. Hope all of our blog readers are having a enjoyable holidays. In other words, I hope you didn’t have to fly anywhere over this Christmas weekend!

I’ve been catching up on some reading including recent articles on invasive alien plants that should be of interest to our readers. I’ll share some thoughts when I get back on schedule next week. In the meantime there’s still another football game to watch this evening and another plate of my mother-in-law’s cookies that need some attention.

Have a safe and happy New Year!

Bees and Pesticides

I had the opportunity to read a disturbing post over at Garden Rant the other day about the insecticide clothianidin and how the EPA required its producer, Bayer, to run tests on the safety of using plants grown from seeds treated with clothianidin for bees. Tests which were, apparently, never carried out appropriately. This post sent me over to another site, AlterNet, which explained the problem in detail. In a nutshell what happened is that the EPA asked Bayer to run some tests on how its new pesticide might affect bees. Bayer was unresponsive at first, but eventually did run some tests (which were not what you would call robust) which showed that bees did fine when flitting around in a field of plants which came from clothianidin treated seeds – at least for as long as the test was carried out.

Then one of our commenters asked for our opinion, and heaven knows, I am always more than happy to offer my personal opinion! So here it is. I am extremely unhappy with both Bayer and the EPA in this instance. They didn’t do what they were supposed to do. It’s as simple as that. Tests were supposed to be run to demonstrate that it is unlikely that clothianidin affects bees. This wasn’t done in a reasonable period of time. Period. As long as stuff like this occurs nobody is going to trust the EPA or the chemical manufacturers. In terms of whether the tests were sufficient (basically some hives in a field of treated plants), well, I would have liked to have seen more depth, but they didn’t seem to be bad studies.

The implication is that, because we don’t have enough testing, clothianidin could be causing bee colonies to collapse. This goes hand in hand with the suspicion that imidacloprid is leading to colony collapse since both of these chemicals are neonicotinoids. We know that these pesticides can get into flowers where bees come into contact with them. The question is whether the bees contact enough to cause hives to collapse (There is no question that these chemicals, at some level, are poisonous to bees – just as almost anything can be poisonous to humans at a high enough dose – even water).

One thing that is lost in this discussion is that SEED TREATMENTS were being examined. A seed treatment is when the seeds which are planted are treated with a pesticide (in this case clothianidin) to protect the seed itself and the young plant from insects. As the plant grows the insecticide will break down and become diluted – And so it is probably not going to be present at high levels in pollen that the plant (which comes from the treated seed) produces. Still, there is potential for this to happen and so it is best if the plants which come from the seed are tested – hence the EPA’s request.

Historically, there are pesticides which have clearly and unambiguously lain waste to bee hives, the most infamous of which was Penncap-M. This was a unique pesticide because it was a microencapsulation of the very dangerous insecticide methyl parathion. The microencapsulation process made this pesticide last longer, and made it somewhat safer to handle, but it also made the pesticide into tiny little beads – about the same size as, you guessed it, pollen. In fruit trees in particular this stuff would become attached to the bees (just like pollen does) and you can imagine the disastrous results. The answer was to limit the use of this poison to certain times of the year and certain situations when bees were not likely to be around. Why wasn’t it just banned outright? Because it worked well and, when used appropriately, it didn’t affect bees (Here I’m giving you the official line – In my opinion its use should have been even more restricted than it was). Penncap-M is not closely related to the neonicotinoids chemically, though it does affect insects’ nervous systems as many insecticides, including the neonicotinoids, do.

You can count me as one of the people who suspect that the neonicotinoids have something to do with colony collapse. I’m not a bee researcher — but it is easy to see how the use of these chemicals might weaken a hive to the point where mites or disease could come in. One of the things that drives me a little nuts though are those people who think that banning neonicotinoids is going to save our bees. It seems quite obvious at this point that these chemicals are definitely not the sole cause of the disease and perhaps not even one of the major contributing factors. They essentially banned these pesticides in parts of Europe, and guess what? They still have bee colonies collapsing. An interesting side note is that historically large-scale losses of bees isn’t as odd as we might think – in fact, we might have seen this disease (CCD) before. Perhaps even in the 1800s. In short, it seems that the answer to this problem is not as simple as banning some pesticides (though restricting their use may be a piece of the solution). I wish it were.

What fir?

OK, it’s the middle of December so I get to indulge my passion for Christmas trees. One of the most interesting projects I’ve gotten to work on during my time at Michigan State is a study to look at alternative species of firs (Abies spp) for Christmas trees and well as for landscape conifers. Firs are fascinating trees that are distributed throughout temperate regions of the northern hemisphere. There are about 50 species, many of which are important for timber, landscaping or Christmas trees.

For those of you that put off your Christmas tree shopping until the end (or want to start thinking about next year’s tree) here are three trees to keep an eye out for.

Korean fir Abies koreana We have several growers in Michigan that are now growing Korean fir. It has relatively short needles that have a bottle-brush arrangement on the stem. The color is often described as dark green, but I’d say the needles tend more to a true green or Kelly green with a silvery underside.

Concolor fir also makes a great landscape conifer

Conolor fir Abies concolor I grew up in the Northwest so I always knew this tree as white fir until I moved to the Midwest. In any case, it’s a great tree. Long, soft-blue needles. Depending on the seed source they can be as blue as a blue spruce. The main draw-back here in Michigan is that concolor tend to break bud early, which makes them susceptible to frost damage in the spring. Their citrus-like scent is hard to beat.

Danish growers compete for the best Nordmann fir in the “Fight for the Golden star” at their annual tree fair.

Nordmann fir Abies nordmanniana Denmark is the leading producer of Christmas trees in Europe and Nordmann fir is their principle species. The Danes like Nordmann because of its deep, dark green color and natural form and symmetry. Europeans don’t like their Christmas trees sheared so they rely heavily on genetics and selection to find trees that naturally have good form. We’re starting to see more Nordmann in the US, both here in the Midwest and in the Northwest. Growers complain that the trees are slow-growing to start but I think some US consumers are looking for a more open, natural-looking tree and Nordmann can fill this niche.

Balanced fertilizers are usually out of balance

I’m in the midst of grading papers for my nursery management class, and something that I’m running across is an incredible number of papers where the students are recommending balanced fertilizers. Why are they doing that? Or maybe an even better question is, what is a balanced fertilizer? A balanced fertilizer is a fertilizer which has three numbers which are about the same, like a 10-10-10. The problem with balanced fertilizers is that they are much higher in phosphorus than what most plants need — at least in relation to the amount of nitrogen and potassium which plants need. Especially here in Minnesota, where there is usually plenty of phosphorus in the ground, this extra phosphorus serves no purpose except to pollute waterways. We have got to break the cycle of just assuming that a balanced fertilizer is the way to go. I get to see a lot of soil tests from old agricultural fields where balanced fertilizers were used for years and years. Usually 10-10-10. What I usually see — with very few exceptions — are phosphorus and potassium levels which are either very high or off the charts entirely. Phosphorus and potassium don’t move readily in the soil while nitrogen does, so every year that you add 10-10-10 in the appropriate amount for your plants needs for nitrogen you’re adding too much phosphorus and potassium. Any extra nitrogen which you add will move through your soil, but P and K will build up year after year (and some will run-off into gutters and drains). So what do I recommend? I like a ratio of about 5-1-2 or 5-1-3 for an N-P-K ratio in a general use fertilizer.

The decline of Extension and the increased need for science-based information

I hate to be the downer this week, given Bert and Holly’s inspired posts, but reality continues to hit – or bite. The budget crises in Washington state continues to gut higher education, and one of the hardest hit areas at WSU is Extension. Land-grant institutions have a federal mandate to provide Extension services, and this sets WSU and similar universities apart from other state schools. Unfortunately, Extension generates relatively little in terms of outside grants and contracts. Land-grant universities like WSU tend to put their dwindling faculty resources into hiring those who can bring in multi-million dollar grants. And as we’ve bemoaned in past posts, that isn’t in gardening or urban horticulture or arboriculture or any of those great topics that you all love to hear more about.

Let’s look what’s happened with Extension specialists at WSU. Before I came in 2004, the Extension plant pathology specialist had retired. The position was refilled with someone else. The Extension entomology specialist retired last year. His position will be refilled with someone to work with the structural pest control industry (there is some money there). The questions that come from the public are shuffled around among other faculty, who may or may not have some partial appointment in Extension. In any case, the public outreach and education aspect of land grant universities everywhere is taking the back seat to bringing in grant dollars and teaching college students. That means fewer Extension Bulletins published or updated and more reliance on well-funded companies to provide their versions – good or bad – of agricultural sciences.

I’m not going to rail about the idiocy of letting public higher education fail in this country through lack of state funding – I’m sure you can see that for yourselves wherever you live. Instead, I want to point out an effort to gather the remnant state forces to have a national impact.

This year I’ve become associated with eXtension (a national group of Extension personnel) in the Community Horticulture Community of Practice. This is a fledgling effort to construct a national web presence containing relevant, current, science-based information on all things horticultural. If you check out the link above, you can click on Garden Myths, where you’ll find information from…Jeff Gillman and myself.

It’s going to take a long time to get this web resource organized and populated with good information – but it’s a start. If you, or someone you know, is interested in helping, be sure to post a comment or email Karen Jeannette, our intrepid coordinator in Minnesota. (I can provide her email if you are interested.)

Not your father’s extension service

We recently received a question on one of my old posts (Dec. 12, 2009) from a blog reader in Iran (yes, Iran) regarding agricultural extension and asking what’s new in how we disseminate science-based information. There’s no doubt that things have evolved in agricultrual extension over the years. There’s an old joke: Guy walks into a county extension office and the agent is sitting behind his desk, crying. The visitor asks, “What’s the matter?” Agent replies, “My farmer died.”

Hey, I said it was an old joke, I didn’t say it was a funny one. Point is, the days of field extension agents or campus-based extension personnel going out and holding a farmer’s hand are long gone. While some may still think of dim-witted Hank Kimball on “Green Acres” when they think of extension (go to http://www.hulu.com/watch/140842/green-acres-my-husband-the-rooster-renter if you miss the reference), most university extension is going increasingly high tech. I’m sure each on my colleagues can provide several examples of recent extension innovations in there area. I’ll provide one that we have just launched here at Michigan State.

Obviously the single biggest tool we have for outreach and extension is the internet. Recently, Dr. Pascal Nzokou, one of the lead members of our Christmas tree extension team launched the MSU Christmas Tree Channel on youtube http://www.youtube.com/user/MSUChristmasTrees

On the Christmas tree channel members of our extension team provide short (1 ½ – 4 minute) videos on various aspects of production: site selection, species selection, pest management, irrigation, nutrition.

There are several advantages of using youtube for these types of videos. First, uploading the videos is easy and straightforward. We had a professional shoot the videos and do the editing but anyone with a digital video camera can shoot videos and load them on to youtube. For short videos it’s easy to upload videos for viewing even at HD resolution eliminating the ‘Invisibale Gardener expereince’. Once the video is loaded you can send the link out to people you think will be interested or include the link on your website. People may also find your video using the search feature depending on the information you include in the description. Lastly, most people that use the web regularly are used to searching and viewing on youtube so there’s high consumer acceptance.

Published: 11/22/2010 2:21 PM

BlogTitleForUrl: not-your-father’s-extensio

DMSO

A few months ago I was interviewed for an article where they asked me whether I thought that a deer repellant which was taken up into a tree would be a good idea. I said sure, great idea. It would last a long time — something that most repellants currently don’t. Well, I just saw the article and I must say that I’m not so sure that it’s a great idea any more.

It seems that the repellant that they’re talking about is basically a combination of hot peppers and DMSO. The hot peppers have been around for a long time. The DMSO not so long — just a few decades really (though there is very small quantity of naturally occurring DMSO in fruits) but DMSO has some properties that concern me. When I was younger I was a competitive runner and I recall certain other runners using DMSO as a treatment for aches and pains. I also remember a run-down house along one of my regular runs selling the stuff via a cardboard sign on the porch. Looked kinda shady. I haven’t seen much DMSO around recently, maybe because it isn’t legal everywhere — at least as far as I can tell.

DMSO is a solvent which crosses membranes, such as skin, very easily. Apparently, if you use it anywhere on your body, it will make your breath garlicy. In terms of toxicity — it isn’t considered very toxic. However, it has the ability to dissolve things, such as poisons (the insecticide imidacloprid for example), and anything which it dissolves can then cross the skin barrier very rapidly right along with the DMSO.

So to me this is a little worrying. I don’t have much experience with DMSO, and I don’t have a problem with professional pesticide applicators who have the proper equipment applying DMSO, but I can’t help but wonder whether this stuff might be just a little too tempermental for the average homeowner to use. Apparently the EPA has it now. Here’s hoping that they’ll make the right decision, whatever that is.

Pesticides and Wildlife

If you follow this blog then you know that I write a lot about pesticides. They’re something that I enjoy reading about and studying. For whatever reason, I find them fascinating. That said, they can be some of the worst things for wildlife. But there are pesticides that are more “wildlife compatible” than others, so today I’m going to cover some of the worst pesticides that you can use in terms of wildlife, and some of the pesticides that might be more acceptable (though far from perfect).

First, here’s a brief rundown of pesticides that have been some of the worst wildlife offenders over the years. Fortunately most of these are gone.

1. DDT – long gone (though I know people who still have old bottles locked up in chemical cabinets here and there). Modern evidence points to it not being as bad for human health (cancer) as many made it out to be, but it was a mess in terms of environmental effects — it built up in the environment (it is stored in the body and is not rapidly excreted — in large part because it isn’t water soluble — so when a predatory bird ate a small mammal who had DDT on (or in) it, all of that DDT would stay in the bird — and the DDT from the next mammal it ate, and so on — this is called biomagnification) and resulted in predatory birds producing thin-shelled, barely viable eggs. Another problem with DDT was that it lingered for a long time — it doesn’t break down quickly. It had other problems too – but the biomagnification and persistence issues were the most obvious and, at least to me, the scariest.

2. Endrin – Relatively closely related to DDT, but a lot more toxic to a lot more animals and so a lot scarier. Once upon a time this stuff was used to all but sterilize fields. Toxic to everything that moves, and, like DDT, it built up in the environment. This stuff was (fortunately) never really used by homeowners.

3. Temik (aldicarb) – Nasty, nasty, nasty. EXTREMELY high acute toxicity, AND it’s water soluble. A pesticide which I have had to use in the past. Apply it to a tree (I was working with pecans when I used it) and that tree’s foliage would be free of any insects. And, amazingly, the stuff didn’t translocate to fruits and veggies – if it weren’t so darn toxic to things besides insects it would have been a great insecticide – some people still consider it a great insecticide. This stuff was known for its misuse. Apply it near a weed which deer eat and that weed would absorb the pesticide and poof! No more deer. Agonizing death too. Wolves and coyotes could be poisoned with just a little bit of tainted deer meat. This stuff wasn’t supposed to be used by homeowners, but, again, it is known as much for its misuse as its use.

Fortunately most of those over-the-top killers are gone or on their way out. Still, in your garden you do have the opportunity to use some poisons which it would be best for you to avoid if you’re interested in saving/protecting wildlife. These poisons are called “broad-spectrum” poisons and they are preferred by many because they kill so many different types of pests. Unfortunately being able to kill many kinds of pests usually also means that they’re able to kill many types of good creatures. Many pesticticides such as sevin (carbaryl), pyrethrin, orthene (acephate), and sulfur are broad spectrum poisons that you should avoid, but here are some that, if you want to conserve wildlife, you should be especially wary of.

1. Permethrin – This is probably the most used broad spectrum insecticide used around gardens today. It will kill just about any insect which it touches and it lasts for about 10 days. It is certainly effective, but it shouldn’t be used by anyone who wants to encourage insects or the birds who eat insects in their gardens.

2. Metaldehyde – This is a very effective slug poison. It is both attractive and deadly to dogs and cats, and is thought to affect birds and small mammals as well though there aren’t as many documented cases of wildlife poisoning as there are of domesticated pets being poisoned.

3. Copper sulfate (Bordeaux mix) – This is an organic fungicide that is often overapplied because it is considered safe. It can limit the plants which grow in an area, and it is extremely toxic to aquatics – keep it away from water. Finally – copper doesn’t break down – as you use it over the years it will build up in your soil – so try to stay away from it.

And finally, here are some which, if they are used properly, are less likely to affect wildlife.

1. Kaolin clay – it’s not popular, but it’s out there if you look for it. This is a type of clay which it sprayed onto plants to protect them from insects. It tends to work pretty well (it’s not perfect), but it has minimal effect on wildlife.

2. Insecticidal soap – It will kill some insects that you don’t want to kill, but it’s a heck of a lot better than permethrin. It is unlikely to hurt mammals or birds.

3. Roundup – The controversial part of me wrote this. Roundup has been implicated as doing all kinds of things to aquatic organisms, but, if it is only sprayed on the leaves of the plant you want to kill, it is not going to cause any significant environmental damage (besides removing a plant that wildlife may want for food).

Want more bird visitors? Nonnative plants may be the answer

We’ve posted before about the native vs. nonnative conundrum, especially as it relates to invasive species. So let’s complicate the issue a bit more by considering how birds are affected by our landscape choices.

About 10 years ago my UW colleague Sarah Reichard and I collaborated on a literature review on the interaction between birds and non-native plants. While we know that invasive plants can displace native plants and create less biodiverse environments, the resulting impact on species like birds is not so cut and dried. And what about noninvasive, nonnative plant species? How do they affect bird populations? Here are some of the practical bits of information that we found:

1) Nonnative shrubs and trees are often chosen for their brightly colored fruits, especially those that produce them in a different season than native plants. Winter color is highly valued by gardeners.

2) Frugivorous birds (those that eat fruit) generally benefit from the introduction of fruiting species as an additional food source, even if the species is invasive.

3) Birds tend to prefer fruits that are red and/or black, or that have red arils or pseudoarils.

4) Birds tend to prefer fruits that offer the most pulp; interestingly, highly invasive plants species tend to have larger fruit displays and therefore higher bird usage than less invasive relatives.

5) Additional food sources can allow frugivorous and omnivorous birds to expand their ranges and/or their breeding seasons.

6) Nonnative shrubs and trees with structural features such as thorns and spikes can provide protection to small birds from predators.

It’s clear that birds are highly adaptive and will quickly learn to utilize new food resources – and in doing so, may contribute to their spread through seed dispersal. It’s enough to make your head spin.

Here’s what I recommend for choosing bird-friendly trees, shrubs and vines:

1) Use native species first if they are adaptable to your site conditions. (Note: many native species, especially those of forested environments, don’t like urban conditions.)

2) Be sure to provide structural diversity in your landscapes – groundcovers, small dense shrubs, larger open shrubs and small trees, big trees, and vines – to provide shelter and nesting habitat.

3) Before choosing nonnative species, check the web for information on invasiveness. The USDA Plants Database (http://plants.usda.gov/) has information on invasive species. If it’s invasive, please don’t plant it!

4) Birds see best in the red end of the color spectrum, so select plants with fruits and flowers that will attract them.

The Garden Professors Go Wild!

It’s ‘Wildlife week’ on the Garden Professors. One of the most common questions that we get when speaking to garden groups is, “What can I do around my home to promote wildlife?” My stock answer used to be, “Throw a party!”, but only a handful of people ever got it so I’ve backed off of that one. Anyway, since the subject of gardening and wildlife comes up so often we’ve decided to dedicate a week to the topic.

Questions about wildlife (the animal kind) always take me back to my undergraduate forestry days at Washington State University and Dr. Zamora’s Wildlife Management course. Even though I’ve always been more of a plant person than and an animal person, I found this to be a fascinating course. In fact, assembling the winter browse twig ID collection was one of my proudest undergraduate achievements. Doesn’t seem like much; but try wandering the Palouse hills in the dead of winter and see if you can indentify 50 browse species without the benefit of leaves, you’d be proud too! In addtion to a notebook full of mounted twigs and a mild case of frostbite, I took away from the course several key principles of wildlife management that have stayed with me over the years.

What do wildlife need? In general, all wildlife need four basic elements: food, cover, water, and space. The specific types and amounts of these elements, of course, will depend on the type of wildlife you wish at attract. Homeowners can provide or enhance these elements through plants or through other, non-living means. Important non-living components include feeders, bird-baths or other water features, piles of rocks or sticks (provide cover for small animals), salt, and standing or fallen dead trees (provide habitat for cavity-nesting birds and mammals). Plants can provide both food and cover. Important plant components in designing for wildlife include evergreen conifers for cover, summer fruits and berries, fall fruits and seeds, winter fruits and seeds, flowers that provide nectar, and trees that provide nuts and acorns.

At this point the questions often turn to the importance natives versus exotics. In light of Doug Tallamy’s book, Bringing Nature Home, many people assume that only native plants can serve these functions. But there are several factors to consider here. First, Tallamy’s discussion is largely focused on co-evolutionary relationships between native plants and native insects, and even here some of the reasoning is stretched thin (see Linda’s Feb. 12 post). There is more to supporting wildlife on a broad scale than insect/herbivore interactions. Non-invasive exotic conifers, for example, can certainly contribute winter cover, vertical structure, and edge effects. And, while some animals have evolved very specific diets (think koalas and eucalyptus), many herbivores are generalists and in some cases even prefer to feed on exotics. So, in thinking about wildlife it’s important to consider function and providing the elements animals need than to simply fixate on whether plants are native or exotic. This is especially true on tough, disturbed sites where natives may be poorly adapted and unable to survive. Habitat provided by an exotic will be preferable to no habitat at all.

Lastly, another factor to consider is whether attracting wildlife around your home is always a good idea. Along with the wildlife we’d like to see, improving habitat may increase the likelihood of running into critters (skunks, raccoons, possums) that we’d rather not encounter on the way to take the trash out late at night. Also, in many parts of the country, people and their pets are encountering large predators such as cougars and bears with increasing frequency. Obviously a lot of this is due to human encroachment into the predators’ habitat, but it may be prudent to consider a ‘defensible space’ strategy as we do for wildfires. Keep the elements that are likely to attract larger animals a safe distance from the house. Stay tuned for more as ‘Wildlife week continues’.

NOTE: Thanks to my high school choir-mate and college soccer team-mate, Tim Schlender for the timely wildlife habitat cartoon.