The Garden Professors™

Master Gardeners are Great, And They Deserve Better

If you’re looking for cat videos, birthday reminders, and a method for spying on old friends then Facebook is pretty useful, but for cold hard facts?

Not so much.

Well, actually we’re overstepping here. It’s really not Facebook. After all, Facebook is kind of like a blank sheet of paper. The paper doesn’t tell the truth or lies, it’s the person who writes on the paper. On the Garden Professor’s Facebook page we do a pretty good job of offering science based information to people. It’s not perfect, but it isn’t bad either. And there are certainly other good Facebook pages too, mostly associated with various Universities.

Another page that did a pretty good job was the Extension Master Gardener’s Facebook Page. This Facebook page is run by a group of Master Gardeners who generally do a great job of telling it like it is, but recently something happened and the posts have been…softer. And those that are science based seem to have some science that we would call questionable at best. For example, they posted links to articles which include information such as this:

“These are natural pest control agents. The bitterness of cucumber peels will ward off ants, moths, mites, wasps and silverfish. Lay cucumber peels in corners of the kitchen, on windowsills or in cabinets … wherever you are having a bug problem. Refresh them frequently, though — decomposing cucumbers will actually attract pests.”

http://farmersalmanac.com/food/2014/04/21/dont-toss-those-peelings/

And this

“It is widely supported that tomato leaves can be poisonous, as they’re in the nightshade family. Tomato leaves, however, are not dangerous if ingested in small quantities, and in fact can be used as an infusion, much like tea leaves.”

http://food52.com/blog/4048-just-eat-it-using-all-of-the-crops-you-grow

Wow. OK.

Is this information, which comes from popular press articles, really research based? We’re not sure….can’t seem to find it in the literature.

The thing is, until recently, The Extension Master Gardeners felt that it was appropriate to post links on Facebook to things that were science based, thought provoking and meaningful. For example, they weren’t afraid to share articles like this:

http://www.slate.com/articles/health_and_science/science/2015/07/are_gmos_safe_yes_the_case_against_them_is_full_of_fraud_lies_and_errors.html

http://www.forwardprogressives.com/6-things-didnt-know-monsanto/

http://www.quora.com/Is-Monsanto-evil/answers/9740807?ref=fb

http://www.geneticliteracyproject.org/2015/05/10/mandatory-gmo-food-label-not-backed-by-science/

http://www.geneticliteracyproject.org/2015/05/18/myth-busting-on-pesticides-despite-demonization-organic-farmers-widely-use-them/

http://www.forbes.com/sites/henrymiller/2015/07/29/why-organic-agriculture-is-a-colossal-hoax/

http://www.nytimes.com/2007/08/28/science/28crop.html?pagewanted=all&_r=0

http://www.geneticliteracyproject.org/2015/02/02/how-your-food-would-look-if-not-genetically-modified-over-millennia-2/

http://entomologytoday.org/2014/06/11/genetically-modified-honey-bees-a-key-technology-for-honey-bee-research/

http://www.geneticliteracyproject.org/2015/01/22/gmo-myth-farmers-drown-crops-in-dangerous-glyphosate-fact-they-use-eye-droppers/

Here’s the funny thing, as far as we can tell, with very few exceptions these articles have been “unshared” by those in charge of the Extension Master Gardeners Facebook page (we checked last week — and we do acknowledge that facebook does some funny things — but we know these were shared and we now can’t find them) — and all of those articles came from one person, Sylvia Hacker.

That’s a shame because these articles make you think, and they’re based on science. I’m not going to say all of the conclusions are correct, but Master Gardeners are supposed to be thinkers and certainly have the mental capacity to read these articles while critically balancing the arguments presented against other things they’ve read. Additionally, Master Gardeners are often asked questions about this kind of stuff. Since they’re asked the questions, isn’t it appropriate to be conversant in what the public at large is hearing about the topic as well as what current mainstream science writers are saying about it?

Look, some people complain or make nasty comments about articles like this because they have strong feelings about certain things. For example they’re strongly anti-GMO or pro-organic. But the thing that separates Extension Master Gardeners from a gardening club is that they literally have a duty to promote science based information such as that contained in the articles which Sylvia posted. To back away from this duty by removing already posted science based articles on Facebook is to allow science to lose.

Sylvia Hacker was recently released from her responsibilities on the Extension Master Gardener Facebook page where, over the course of only about 2 years, she helped raise the number of likes from about 3,000 to over 13,000 because she thought it was important to be proactive and to spread relevant science based literature which the general public was reading and responding to – regardless of whether it was controversial or not. Here is the letter she received regarding her dismissal. We leave it up to you to decide whether her release was appropriate or not.

Sylvia

The Cooperative Extension Services across the United States are tasked with disseminating objective, research-based information. Some of your recent posts to the Extension Master Gardener Facebook page have not met that standard. Some have been needlessly confrontational while others have linked to popular press articles with insufficient scientific documentation. You noted in a message on the National EMG Social Media Team “that Extension isn’t timely, can’t respond to trends or current issues” and that its content is “too boring.” Given your apparent lack of respect for Cooperative Extension as a whole and its affiliated program, Extension Master Gardeners, I regret to tell you that you will be removed as an administrator of the Extension Master Gardener Facebook page.

Posted by Jeff Gillman and Linda Chalker-Scott

When Plants Attack! (each other)

When you talk about killer plants, your mind may conjure images of a man-eating plant in “Little Shop of Horrors,” insect-eating Venus flytraps or poisonous plants like deadly nightshade.

While all of those scenarios are interesting in and of themselves, what about plants that attack other plants?

I’m talking, of course, about parasitic plants. These plants thrive on stealing nutrients from other plants, either weakening them or, quite possibly, killing them.

Parasitic plants connect themselves to a host plant and siphon off the sugars that plant produces and the nutrients it pulls from the soil. These plants often bend the definition we have in our heads of plants, since they don’t have to behave like other plants that make their own food.

Probably the most well-known (and beloved) parasitic plant is mistletoe. The plant that gives us the warm fuzzies and romantic feelings around the holidays makes its living by feeding off of the trees in which it lives. They don’t talk about that aspect of the plant in all those Christmas songs. It doesn’t kill the tree, but a heavy infestation can weaken a tree and slow its growth.

Indian pipe (Monotropa uniflora). Photo courtesy GP Raymond Eckhart

While they are few in number, there are some parasitic plants you may run into. Another parasitic plant in our part of the world is the Indian pipe (Monotropa uniflora), a white, chlorophyll-free plant that resembles a smoking pipe as it unfurls from the forest floor. Without chlorophyll, it can’t make its own food, so it connects itself to a nearby tree (usually beech) for nutrients.

Another plant, called a beech drop (Epifagus americana), also makes its living in the same manner. A plant called squaw root or bear corn (Conopholis americana), because it resembles an ear of corn growing out of the forest floor, is a parasitic plant that connects with the roots of oak trees.

An infestation of dodder beginning in an annual bed. Photo courtesy Ann Berry.

These plants may cause a little damage to their host plants. This week, though, there seems to be something more sinister afoot. I received two different calls about the same parasitic plant this week, from different parts of West Virginia (one of which came from Ann Berry, associate vice president for marketing and outreach at WVU). It seems that the problem here was with a parasitic plant called dodder (Cuscuta sp.). Despite the name, I assure you that this plant does not dodder around when it comes to feeding off other plants. This plant can severely infect and potentially kill any plant it touches.

Seeds of the plant germinate in the soil, so it starts life just like any other plant. Once germinated, though, the seedling has about 10 days to find a host plant to attach to and begin feeding. But this is not left to chance — it seems that dodder is a pretty good hunter. Scientists have determined that dodder can, in a way, sense chemical signals from nearby plants and grow directly toward them.

Dodder is an odd-looking plant, and many people don’t even know to classify it as a plant. It grows in long strings, often without leaves (or only having inconspicuous ones). Different species can be different colors. The one that is most common here is often a yellow-orange color.

cuscuta Haustorium — Dodder, above, inserts a haustorium into its host plant.

Once the dodder touches the soft tissue of a plant (leaves or stems), it inserts a structure called a haustorium into the plant. Haustoria insert themselves into the plants vascular tissue (veins) and siphons off the water, sugars and nutrients. After the connection is made, the dodder plant detaches its roots from the ground and becomes completely reliant upon the host plant. Luckily it has trouble attacking woody plants, so it mainly goes after herbaceous ones.

One connection is bad enough, but the dodder twines its way around the plant as it grows, resembling what some would call “silly string.” Everywhere the dodder touches the host, it sends in new haustoria to strengthen its connection. If other plants are close enough, the dodder will grow outward through the air to ensnare another host. It can easily grow to encompass many plants, covering them completely and eventually strangling them or starving them out.

My advice to both of the callers this week was to remove as much of the plant as possible, as soon as possible. Unfortunately, the plant can regrow from the connections it makes with the host plant, so you often need to remove whole parts of the plant or the whole plant itself. If it has only made one or two connections, you may be able to control it just by removing the dodder from the plant.

Dodder is hard to see on the ground as it germinates, so it is only usually spotted after it has attached and grown on a plant. If you do happen to catch it before it attaches to a plant, cultivating the soil to break it up and removing as much by hand as possible will help. Unfortunately, there is no spray or control method that will kill the dodder without killing the host.

Dodder is definitely a bizarre plant that many have not seen. Keep an eye out for it this year, since it seems to be cropping up in unexpected places. It just goes to show you that sometimes it’s a plant-eat-plant world out there.

This article was originally published 08.09.15 in the Charleston Gazette-Mail. You can find more article at wvgardenguru.com.

It’s the Next Best Thing Since Draft Beer: New Plants and Their Proper Evaluation

'Graham Thomas' rose — ‘Graham Thomas’ rose

With many new nursery catalogs arriving in my mailbox at work for 2016 introductions, I thought I would focus this blog on “new” plants. With all the publicity and marketing that goes on for new plant introductions, you would think that they are the next best thing since draft beer or even bread! I am a bit cynical and question whether these new plants really live up to their performance expectations and ornamental attributes. With so many new hydrangeas, coneflowers, coralbells, spireas, etc. released each year, you may ask why am I so cynical? Why would I not jump on the bandwagon and promote all of these new plants like so many garden centers are doing across America? Let me explain.

A decade ago, I conducted research trials evaluating 20 new or recently introduced cultivars of “hardy” shrub roses, many of which are not even on the market anymore. I chose three locations in the state of Wisconsin, each having their own unique soil types, pH, soil drainage and fertility, rain/snowfall and cold hardiness zones. I replicated each of the 20 cultivars ten times at each location and arranged them into blocks with each cultivar represented in each of the ten blocks. The roses were randomly selected for each block and planted, mulched, watered with an application of a slow-release fertilizer. Plants were watered for the first year only as needed. To properly analyze plants for various traits, I allowed the roses to establish for a year with evaluation initiated the following spring. The only care the roses received the remaining years were application of a slow-release fertilizer, weeding and pruning of dead wood following winter. I was trying to replicate conditions that are common in most landscape settings. I did not spray any insecticides or fungicides to any of the roses, regardless of how bad they may have looked due to pests.

After the first winter, I evaluated the roses for winter injury, which they all experienced. The roses were all on their own root systems so if they died back significantly, the new growth would come from the same root system and produce flowers that spring. To some extent, they all grew, though voles killed some of the roses. After the roses starting growing, I evaluated them monthly at all three locations for insects and diseases as well as flowering (amount, size, duration of bloom, etc.). I also measured the plant’s height and spread. A few roses had good fall color. The first year of the trial, the roses all bloomed prolifically. So, one would think that all 20 cultivars are ideal. Not so fast, or “but wait, there’s more” as the television salesman would say to viewers in TV land about a new product. The “real” evaluation started in year two.

In year two, amount of dieback and winter survivability was recorded. To my surprise, the roses in the zone 3 location (boy, that’s cold) had better winter survival than the roses in my zone 4 and 5 location! This is due to consistent and significant snowfall in the most northern location compared to sporadic snowfall and lower amounts in the other two locations. I also evaluated the roses during the summer and fall for flowering, pests, and hip production. Contrary to the catalogs, many of the roses had hips, but some of them never colored up before the cold temperatures arrived at the three locations. Flower production was cited as being continuous all summer by their introducers, however, this was not true for some of the cultivars evaluated. Disease resistance was the most alarming quality I evaluated with many of the so-called “disease resistant” roses being the exact opposite. I explain all these variables to demonstrate what is involved in proper plant evaluation. For a complete report of my rose research trial, see: Jull, L.G. 2004. Hardy Shrub Rose Research Trials. Combined Proceedings of the International Plant Propagators Society vol. 54:429-434.

Knockout® rose is very disease resistant with non-stop blooms, but not hardy in zones 3-5 without significant winter protection Photo credit: http://www.gardeningknowhow.com/wp-content/uploads/2011/08/knockout-rose-400x600.jpg — Knockout® rose is very disease resistant with non-stop blooms, but not hardy in zones 3-5 without significant winter protection Photo credit: http://www.gardeningknowhow.com/wp-content/uploads/2011/08/knockout-rose-400×600.jpg

Now, you may ask, “Why are these new plants, including roses, promoted by these large nurseries as being the best plant around when in effect, they are not?” Many new introductions are from nurseries that trial their plants in their location only. So a plant that performs well in the state of California might not perform the same in Michigan and vice versa. There isn’t the scientific rigor applied to these new plant evaluations that would occur by non-biased, university researchers who have no stake in selling or promoting plants to the public. This is where the beauty of applied, scientific, university-based studies can play a huge role.

Also, these new plants should be evaluated over numerous years, at various locations/soil types, climates, with appropriate replications of each new plant in a random arrangement (not all planted together). This type of quality research is done by a few large nurseries but it is seldom done this extensively by others anymore as demand for new plants is never satisfied and the cost of trialing over several years and locations is too costly.

Unfortunately with increased costs and significant budget/program cuts, most university research is now geared toward larger, basic science studies that have high indirect costs built into the grants. These funds, usually 50% or more of the grant total, go directly to the university to cover overhead. The researchers do not see or can use overhead funds. Ornamental plant evaluation research is now considered either non-fundable by granting agencies, not “scientific or scholarly” enough by their own departmental colleagues or provide significant overhead funds back to the university.

Some researchers rely on their various nursery and landscape associations for small amounts of research support, while others try to piece meal together small amounts of research funds. With the increasing costs of land (yes, we do have to pay for research space at university research stations), plants (not all are freely given to the researchers), labor, supplies, etc., it is becoming critically important to seek alternative funding sources as most federal and state granting agencies do not fund ornamental plant evaluation research. Many of the new initiatives for federal grants seek to fund food crop based research, especially in organic and sustainable food production. Applied ornamental horticulture plant evaluation research at universities has plummeted with most new plant evaluations conducted by the large nurseries that introduce these plants.

There is another source for evaluation of these new plants. Various arboreta and botanical gardens around the U.S. are conducting evaluation trials. I am a fan of these studies as these gardens and evaluators are also not in the business of selling plants and can provide some analysis, though it is usually only at one location. Richard Hawke, Chicago Botanic Gardens Plant Evaluator and Horticulturist, has done an excellent job of evaluating many species of herbaceous perennials and a few woody plants. He publishes Plant Evaluation Notes: (http://www.chicagobotanic.org/research/ornamental_plant_research/plant_evaluation), a series of wonderful publications that help both the amateur and professional gardener to choose appropriate plants for the Upper Midwest. There are other botanical gardens and arboreta that do the same, with evaluations based on their local climatic conditions. I often rely on Mr. Hawke’s recommendations when choosing herbaceous perennials in my Wisconsin garden and have yet to be disappointed.

Chicago Botanic Garden Plant Evaluation Notes Source: chicagobotanic.org — Chicago Botanic Garden Plant Evaluation Notes
Source: chicagobotanic.org

So the next time a new plant comes across your way, think twice before buying it. There is the philosophy “Buyer Beware”, and I do recommend people to buy plants, but instead of buying 10 of one cultivar, try one or two of the new plant and make a judgment call the following year or two after you planted it. This is especially important for landscapers who design and plant large amounts of plants. You might be surprised to see the “best thing since draft beer” plant being anything but that. As some of us know, there is nothing better than draft beer (or whatever beverage you really like).

Laura Jull, Ph.D. aka The Lorax

When half a flower is the wrong color…

If you’ve spent enough time around flowers, you’ve probably seen this. It isn’t exactly common, but it happens, and is so distinctive that you’ll almost always notice when it happens, as I did on one of my gladiolus the other day.

Everything else is as normal, but a chunk of the flower is white instead of the usual soft peachy white.

What we have here is a sectorial chimera. Chimera means an organism with two (or more, I suppose) genetically different cell types, and a sectorial chimera is when there is one distinct section of the plant made up of a different cell type.

And why is this showing up in my usually pink gladiolus? Well, somewhere early in the development of this flower spike, there was a chance mutation in a cell. That mutation stopped those cells from producing the usual pink pigment, so the mutant cells make white flowers. The new mutation and the original cells continued to grow and divide, so some of the flower is from the newly mutated white form, and some is the original cell type.

Now, when people hear the word “mutant” they either think x-men or nuclear fallout, but the fact is mutations are a perfectly common, normal part of everyday life for organisms, and of course are critically important to continuing evolution.

This type of bicolored flower is cool looking, but certainly a one-off. Sectorial chimeras are very unstable. Next year, most likely, the flowers will just be pink again, or possible a branch will send off pure white flowers. So when you see a sectorial chimera in the garden, take a picture, put it on facebook, and enjoy it because it probably isn’t coming back.

Scientific Beekeeping

Honey bee (Apis mellifera), Courtesy of Charles Sharp at Wikimedia Commons

When I first moved to the country in the late nineties, one of the first things I wanted to do (after establishing several vegetable gardens to indulge my tomato obsession) was to become a beekeeper.

So I took a six week course sponsored by West Virginia University, read the full documentation available from the University of Maryland and Penn State as well as back issues of beekeeping magazines, and checked with some hobby beekeepers in the area.

Unfortunately, at that time, honeybees were being devastated by an invasive species … the Varroa mite (Varroa destructor), and the amount of effort needed to keep colonies free from them discouraged me, and the message I was getting from experienced hobby beekeepers was one of “be prepared”, and “I’m, regretfully, giving it up because of the effort involved.”

Basically … too much work … not something I was willing to commit to.

But I never lost my fascination with them (and other bees and wasps, for that matter.)

Then in 2006, I started hearing about Colony Collapse Disorder, or CCD, and it was while researching it, that I found the site of Randy Oliver, a biologist who also made his living beekeeping.

The site is Scientific Beekeeping.

From his About tab.

I started keeping bees as a hobbyist around 1966, and then went on to get university degrees in biological sciences, specializing in entomology. In 1980 I began to build a migratory beekeeping operation in California, and currently run about 1000 hives with my two sons, from which we make our livings.

In 1993, the varroa mite arrived in California, and after it wiped out my operation for the second time in 1999, I decided to “hit the books” and use my scientific background to learn to fight back.

The site is not a beginner’s “how to”, but a way to share what he has learned with others:

What I try to do in my articles and blogs is to scour scientific papers for practical beekeeping applications, and to sort through the advice, opinion, and conjecture found in the bee magazines and on the Web, taking no positions other than to provide accurate information to Joe Beekeeper.

(If you’ve been following my blog posts here, then you’ll probably recognize the pattern of places that rise quickly in my judgment, as ones I like)

The site has become my “go to” source for all things related to honeybees, and I recommend it to others who want to stay abreast of the subject.

Scientific Beekeeping

Robbers in the garden

Salvia azurea (maybe my favorite salvia in the world — sky blue flowers in late summer/fall, hardy to zone 5) is blooming in the garden, and the bees are all over the flowers. But while some are poking their heads into the flowers to drink nectar and transferring pollen as they do so, others are up to something more sinister.

This carpenter bee looks like it is pollinating. It isn't. — This carpenter bee looks like it is pollinating. It isn’t.

The evidence of what they are up to is clear if you look closely at the side of the flowers after they leave.

The little hole at the base of the flower is clear sign of an illegal break in.

See the little hole in the base of the flower? That is where the carpenter bee bit a hole in the flower to get access to the nectar instead of going in the front of the flower as one would expect.

This phenomenon is called nectar robbing because it is an evolutionary betrayal of sorts. Flowers have evolved nectar to lure bees and other pollinators into the flower, so the bees will pollinate while getting their sugar fix. When the bees nectar rob, they’re getting the payment without doing the actual pollinating.

So why bite a hole in the side of the flower instead of just going in the front? Well, many flowers have evolved flower forms that make the nectar hard to reach by anything but their preferred pollinator, the species that most effectively moves pollen from plant to plant. In the case of this salvia, the nectar is down at the base of the flower, and only accessible to bees with long tongues, like whatever species normally pollinates it in its native range in the US plains. In other words, it is out of reach of the carpenter bees to save it for another bee, probably a bumble bee. Which works great to avoid wasting nectar on sub-optimal pollinators… unless, of course, those bees become robbers.

So next time you see bees on your flowers, take a look… they might just be robbers, not pollinators.

Perennial Funday: Eriogonum allenii ‘Little Rascal’

I’m going to keep posting about perennials that deserve more attention until somebody makes me stop. The fact that my subject is, once again, yellow… is merely coincidental

Definitely was a crowd favorite during the Perennial Plant Association annual Symposium’s grower tour (mentioned in my previous post). These photos were taken at Emory Knoll Farms north of Baltimore; I believe that they were trialing and/or including it in their plant selection for green roof use.

Eriogonom allenii 'Little Rascal' at Emory Knoll Farms — Eriogonom allenii ‘Little Rascal’ at Emory Knoll Farms

Thanks to Mary Vaananen, Jelitto’s North American operations manager (and goddess of perennial plant knowledge), who just happened to be standing next to it, full of 411, when I squealed “WHAT the (blankety blank) is THAT?!” My compadre Paul Westervelt added more info, as he’s also a plant geek deluxe (and manager of the annuals and perennials section of Saunder Brothers Nursery). D’oh. Plus you rock gardening fanatics probably know this cutie as well (I may have first seen this in one of Joseph T.’s talks, now that I think about it).

Eriogonum allenii, shale barren buckwheat, is native to counties that comprise the Virginia Highlands plus those on the West Virginia side of the line in the same region. Within these counties, the scattered populations reside in the botanical wonderlands called the shale barrens.

This floriferous selection ‘Little Rascal’ is indeed from Jelitto, so you too can obtain seeds of this rarity (along with detailed germination/growing instructions). Jelitto lists hardiness to USDA zone 5. As with most species from the barrens, it requires plenty of sun and excellent drainage.

Stocky and slightly shrubby in habit, the coarse grey-green green foliage was, when I saw it at the end of July, completely smothered in deep gold flowers. Simply gorgeous. It was abuzz with bees of all sorts, including insanely happy honey bees that could barely attain lift-off. I have a plot of regular-old-buckwheat (same family, Polygonaceae), but our spoiled-rotten bees always seem underwhelmed. Wait till they get a load of this!

A new excuse for bad pruning

I spent last week in Orlando at the ISA annual meeting (that’s the International Society for Arboriculture). It’s a great venue for networking with colleagues and hearing about the latest tree research. And once in a while I’ll have a WTF moment. (That stands for Why Trees Fail in case you’re wondering.)

My WTF experience this year revolved around some new terminology and techniques. I learned there are now “environmental arborists” who practice “retrenchment pruning.” In the last few days I’ve tried mightily to find some standard definitions from reputable sources. I don’t know what an environmental arborist is, since it’s not a certification (like an ISA certified arborist) nor is it a university degree program (like urban forestry or environmental horticulture). It seems to be a self-anointed title.

This is what a mature oak should look like. — This is what a mature urban oak should look like.

But the real WTF issue is retrenchment pruning. I looked in vain for published research through my usual data bases and found nothing – other than two articles in Arboricultural Journal (which is not the same as ISA’s journal – Arboriculture and Urban Forestry). Neither of the articles presented experimental evidence to justify this radical approach to pruning trees. Instead, they are more philosophical in nature, with a smattering of ecological theory.

Fortunately, retrenchment pruning methods are easily found on the internet, along with horrific pictures illustrating the results. As described on various websites, retrenchment pruning imitates the natural process of aging. Practitioners remove live branches or partial trunks to reduce the size of the tree and prevent future failure. These aren’t clean cuts, either: they’re “coronet cuts” or “natural fractures.” The rationale described in one of the Arboricultural Journal articles is that these jagged broken branches and trunks “promote specialist habitats and enhance colonisation rates of niche species.” In other words, this technique creates large wounds that are easily colonized by various insects and microbes.

An example of natural fracture pruning (http://www.countytreesurgeons.co.uk/veteran.html)

So apparently we’re expected to ignore the well-established field of woody plant physiology (which happens to be my specialty) and related practical bodies of knowledge (e.g., formal and informal pruning techniques of said woody plants) and start hacking away at mature trees. In doing so, we’re removing live tissue and creating large wounds. This has the effect of both reducing photosynthetic potential of the tree as well as opening it up to possible pest or disease invasion. But nowhere are these possibilities discussed as part of the “natural aging process.” Nor was there mention about how to manage the epicormics shoots that result from improper pruning. And they do need to be managed.

These are epicormic shoots resulting from topping this tree.

I saw some very angry arborists at the ISA meeting who were incensed at the idea that we should deliberately malprune trees. But others seemed quite excited with this new philosophy. To paraphrase one of my plant physiology colleagues, “Give a bad arboricultural practice a catchy name and it magically becomes legitimate.”

Pollination strategies can lead to allergy woes

This article was originally published in my weekly newspaper column in the Charleston Gazette-Mail. Articles are archived at wvgardenguru.com.

A quick selfie with President Gee. He's perfected the art of the selfie. — A quick selfie with President Gee. He’s perfected the art of the selfie.

A few weeks ago I made my way to South Dakota for the annual meeting of the National Association of County Agricultural Agents (where fellow GP and I made the rounds at the trade show scrutinizing wacky products). It is a fun conference made even more special this year by the fact that WVU President E. Gordon Gee was in attendance as the conference co-keynote speaker and recipient of the Service to American/World Agriculture award. But I digress…..

Two days into the conference something wasn’t quite right. I kept feeling worse and worse, and by Wednesday I was confined to my hotel room (save for a venture out to the conference banquet for dinner). I would not have been functional for the rest of the trip save for the kindness of a co-worker who went through the pharmacy red tape to procure and deliver “the good stuff” to my hotel room.

I thought I had a sinus infection at best (I get them often) and the flu at worst (yes, it was really that bad). But guess what — I’m just really allergic to South Dakota. Two days after my return, I was nearly back to normal (well, my normal, anyway).

Those who know me know that I suffer from the occupational hazard of allergies. Irony dictates that my allergies are only to about two dozen plants and two molds (that occur in mulch/compost). Lucky me!

Lots of corn surrounding my hotel in the outskirts of Sioux Falls. — Lots of corn surrounding the outskirts of Sioux Falls.

My best guess is that I had a reaction to the corn pollen of South Dakota. It makes sense — while we do grow some corn here in West Virginia, the Mount Rushmore State boasts an estimated 4.75 million acres of corn. I don’t think I was tested for corn pollen allergies, but since corn is not a major crop here, it may not be part of the common test.

I tell this story not for sympathy (well, OK, maybe a little) but it brings up a good illustration about pollination strategies of plants.

Scanning electron microscope image of pollen grains from a variety of common plants: sunflower (Helianthus annuus), morning glory (Ipomoea purpurea), prairie hollyhock (Sidalcea malviflora), oriental lily (Lilium auratum), evening primrose (Oenothera fruticosa), and castor bean (Ricinus communis).

You see, plants like corn rely on chance and wind to spread their genes around. In corn, the pollen drops from the male flowers (the tassel on the top) to the stigma of the female flower (the end of the silk sticking out of the cob). The process relies on lots of pollen being released into the air, since there is a good chance that a lot of it will miss the target. Corn pollen is usually heavy, therefore it doesn’t blow too far from the plant (unless there is lots of wind).

This is why you don’t get a good corn crop if you don’t have a big block of corn in the garden — just one or two rows doesn’t drop enough pollen to pollinate all the flowers. When the silks don’t get pollinated, you’ll end up with incomplete cobs missing kernels. This can also happen if the corn is in bloom during a long period of rain — the rain washes all of the pollen off before pollination can occur.

Most of the major allergen-producing plants are wind pollinators — trees, grasses, ragweed. They all release copious amounts of pollen into the air hoping for it to land in the right place.

Some plants still rely on pollen getting moved from plant to plant or flower to flower, but they remove the chance involved with wind pollination. These plants have a stickier pollen that stays on the flower and waits for something to come along and move it — a bee, a butterfly, a moth, a hummingbird, etc. These plants hold on to their pollen and have the more directed approach of getting a courier to make a direct delivery of their pollen between flowers.

Since these plants don’t leave the pollination to chance, they generally produce less pollen. Some good examples are fruit trees (apples, peaches, pears), sunflowers, squash, goldenrod and roses. Since they don’t release it into the air, they usually aren’t considered major allergens.

Still yet, some plants want to take no chance with their next generation. Self-pollinating plants don’t rely on pollen being spread to different flowers — they take care of business themselves. These plants are perfectly fine without crossbreeding with other plants.

Sometimes, these plants are so dedicated to self-fertilization that they make it difficult for the pollen to leave the flower. Bean flowers have a lower lip that curves upward to protect the reproductive parts inside. Tomato flowers are nearly completely enclosed. You may see bees going from flower to flower, but their search for food is in vain — they can’t get into the flower. Their buzzing does help dislodge the pollen inside the flower, but they don’t have access to spread it around. Producers that grow tomatoes in greenhouses where there is no wind to knock the pollen loose either buy boxes of bumblebees to release in the greenhouse, or use something like a vibrating toothbrush to help the flowers self-pollinate (no joke).

This is why you can plant two different tomatoes just a few feet apart and not have them crossbreed, but you would have to plant squash up to two miles apart (or protect the flowers) to guarantee that you get the same variety if you plan on saving seeds. This is why the most commonly saved seeds, at least in this area, are tomatoes and beans — they are easy to guarantee that you won’t get something other than what you plant.

So if you learn anything from this article, check out how plants pollinate before you save their seeds, and take plenty of allergy meds with you if you go to South Dakota.

Cool Plants for Late Summer

I thought today’s post would feature two awesome plants that are relatively new or unheard of in the industry. Both of these plants have performed well in my own garden and survived our two hardest winters recorded since the 1970’s. Many plants suffered severe winterburn or even death due to extremely low temperatures, but not these two plants. They may be harder to find in the nursery/garden center, but are well worth it and have huge ornamental impact all growing season.

The first is variegated fiveleaf aralia, Eleutherococcus sieboldianus ‘Variegatus’ (formerly Acanthopanax sieboldianus ‘Variegatus’). I know, a really horrible, long scientific name for such a great plant. Now before I go on about this particular cultivar, I need to let everyone know that this is the cultivar you want, NOT the species that has all green leaves. The straight species is weedy, grows too large for most landscapes and is not colorful. The variegated cultivar is a real showstopper! It is low maintenance, grows slowly and rarely needs pruning. This medium-sized shrub grows about 5-6’ tall and wide in the northern U.S. growing larger in the south. The natural form is upright, rounded with long, arching branches. Suckering at the base of the shrub is slow, hence the plant does not become a nuisance in the garden. Variegated fiveleaf aralia is adaptable to most soils and pH, tolerates sandy and poor, dry, clay-based soils, will stay variegated in shade and will not scorch in full sun. It is quite drought tolerant with no pest problems. Deer and rabbits seem to leave it alone.

The foliage is quite clean with 5-7, bright, cream to yellow variegated leaflets with an emerald green center. There is no fall color to talk about, however, the brightly colored leaves mix well with other yellow, white or purple flowering/foliaged plants. The stems do have 1-2 curved prickles on them at a node, but they are short. Unlike its straight species, ‘Variegatus’ rarely flowers or fruits so the plant does not become invasive.

This plant is native to Japan and was highly promoted as an outstanding urban tolerant plant by my former graduate advisor, the late Dr. J.C. Raulston of North Carolina State University. He tested and evaluated thousands of landscape plants for adaptability to the southeastern U.S. and a few of those plants are actually hardy up in zone 4b.

Another great plant that I am more and more impressed with each day is a relatively new release from Iseli Nursery, Boring, Oregon. It is NORTH WIND^® maple (Acer ‘IsINW’). This smaller, 15-20’ tall, ornamental maple is part of Iseli’s Jack Frost^® series of hardy, ornamental maples. Through testing across the country, this maple has proven hardy to zone 4a without any dieback, unlike Japanese maple (Acer palmatum). One of the parents of this great hybrid is the Korean maple (Acer pseudosieboldianum), which is also zone 4 hardy.

NORTH WIND® maple (Acer 'IsINW') — NORTH WIND® maple (*Acer* ‘IsINW’)

The beauty of NORTH WIND^® maple is that it combines the cold hardiness of Korean maple with the outstanding leaf qualities and deeper leaf lobes of the Japanese maple, one of the suspected parents, but with one exception. NORTH WIND^® maple new leaves are bright orange! The color of these leaves lasts longer in the growing season in cooler climates. I have a young tree in my yard and the leaves are still orange, even this late into August. The older leaves gradually fade to green in midsummer. The orange-red fall color is superb and makes a real eyestopper in the autumn landscape. For best color, plant the tree in full sun to partial shade.

Closeup of leaves of NORTH WIND® maple (Acer 'IsINW') — Closeup of leaves of NORTH WIND® maple (*Acer* ‘IsINW’)

NORTH WIND^® maple is pH adaptable and grows best in a moist, well-drained soil. I do not know yet how heat or drought tolerant this species is, but if anyone is growing this plant in southern climates, please let me know how it is doing.

Laura Jull, Ph.D. aka The Lorax