Costs and benefits of pre-plant root manipulation

Spring has sprung here in Michigan; time to get cracking on lots of projects. One of our new projects is an investigation of pre-plant techniques for dealing with root systems on container grown trees. As many of you know, Linda Chalker-Scott is advocate of bare-rooting trees before planting to correct potential root defects before planting. As some of you may know, I’m skeptical of this approach. It’s not that I think root systems are perfect – far from it. But we lack sufficient information to know whether the costs of bare-rooting (time/effort, stress on the trees) warrant the benefits. We also have little information on how species vary in responding to bare-rooting. From the experience of foresters and bare-root liner nurseries we know that some species are highly sensitive to storage and handling when they’re bare-rooted. When I worked for International Paper, we had little difficulty transplanting sycamores bare-root; whereas we often encountered severe dieback or mortality with sweetgum. Likewise, shade tree nurseries often encounter difficulty establishing oaks, baldcypress, and hackberry from bare-root liners. In fact, J. Frank Schmidt and Sons nursery, one of the largest producers of shade tree liners has discontinued production of bare-root hackberry lines and only produces them as container stock.

As I said, I’m skeptical that putting a tree through the trauma of bare-rooting is worth the potential benefit. But I’m also open-minded and willing to conduct an objective trial to see what’s what. As an aside, I was skeptical about root-shaving before we conducted our own trial and was impressed by the results. For our current study we planted 96 container-grown shade trees last week at the MSU Horticulture Teaching and Research Center. Trees includes three cultivars: ‘Bloodgood’ London planetrees, columnar tulip poplar and ‘October glory’ red maple. We assigned the trees at random to one of four treatments: Control (no root treatment), Shave (outer roots removed before planting) and two bare-root treatments – Bare root – Wash (trees were bare-rooted by washing the roots with water) and Bare root – Airspade (trees were bare-rooted using an airspade). The planting crew consisted of my technician, Dana Ellison; my new Master’s student, Riley Rouse; my undergrad assistants, Becky Pobst and Alex Love; and Linda, who was on-hand to provide quality control on the bare-rooting operations.

For her M.S. project, Riley will be tracking performance of the trees over the next two years. Her measurements will include tree survival and growth as well as measures of physiological responses such as plant water potential and photosynthetic gas exchange. Next fall, after two growing seasons, we will dig a subset of the trees with a tree spade and inspect the root systems to determine the effect of treatments on root system development. In the meantime, here are some photos from last week’s festivities.

 

Right tool for the job. MSU Beaumont Nursery provided a big assist by augering the planting holes.
Tulip poplar roots before shaving
Tulip poplar after shaving
Alex cleans up a planetree with the airspade
Dana’s excited to be washing roots.
Riley washing up a maple – don’t worry the cicling roots come off next…
Light and easy. Becky after airspading a tulip poplar
Wait’ll purchasing sees this… A wading pool is perfect for pre-soaking roots before washing and for storing until planting.
Easy to smile when it’s a Control tree…
Getting a little kinky… Root at the end of the felco’s bending back on itself – corrected after the photo-op.
Looking a little wilty. TheBare-root maples required the greatest root removal and correction
Trial plantation at the end of the planting
Can’t pull off something like this without an awesome crew!

My New Project — The Plants We Eat

By Jeff Gillman

The logo!

I love stories, and my favorite stories, as you might guess, are true stories about plants. One of the things that I’m best known for here at the UNC Charlotte Botanical Gardens is telling random stories about some odd tidbit or another to students trapped in my classes or visitors locked into garden tours, but recently I found a new way to share my collection of those eclectic plant stories: Podcasting. Not only do I get to talk about all the things that I love to talk about, only those people who really want to hear about them have to listen. It’s a win-win!

Recording the podcast!

From apples and artichokes to digitalis and peyote, our world is full of amazing plants that we interact with on a daily basis. This greenery can sustain us, intoxicate us, cure us of disease, and even kill us.

I have had the opportunity to read about and work with an incredible variety of plants, but the ones that I find most fascinating are those we ingest as food or medicine, and that’s what this podcast is about. From toxic honey made from Rhododendrons to the incredible photosynthetic efficiency of sugar cane and the natural genetic modification of sweet potatoes there are an incredible number of stories that the plants around us have to tell, but if you’re just interested in growing these plants then we have you covered there too. I am doing these podcasts with a friend of mine, Cindy Proctor, who loves to talk about how to grow these plants, so there’s plenty of that in the podcast as well.

Rhododendron from which Mad Honey is made

So to make a long story short, we would love it if you would take the time to listen to our podcast. You can find it on the podcast app on your iPhone or on Sound Cloud, or here at the Botanical Gardens website.

And since we’re new at this we would love it if you would let us know what you think. You can comment on the blog post here, or on the post on Facebook, or feel free to write to me at jgillman@uncc.edu.

It’s all about location, location, location

Whenever we (the Garden Professors and our community) answer garden questions, we almost always will ask the location of the garden.  I’m sure this frustrates some people who think that plants act the same wherever they are.  However, this is not the case.  There isn’t a one-size-fits-all to most garden questions.

For example, I work on the east side of Nebraska in Omaha, along the Missouri river.  The environment (weather, soil, etc) here is vastly different than where I’ve spent most of my life in West Virginia.  I had to re-learn how to answer questions when I moved.  The soil pH is different (I’m still lamenting the fact that I can’t grow blueberries in Nebraska), the precipitation is much lower.  Even now when I appear on the statewide gardening show Backyard Farmer, I have to keep in mind the location of the incoming question.  The western side of the state is even drier than the eastern side, the growing season much shorter, and recommendations are vastly different.

The difference of where plants can grow and can’t is even more apparent when you travel to vastly different climates.  I recently came back from a trip to the tropical paradise of Costa Rica.  Many of my traveling partners and friends back home were blown away with the abundance of plants growing in yards, farms, and even in the wild that cannot grow “back home.”

The most common bedding plant in lawns were a popular holiday favorite here in the states – amaryllis.  They were planted in abundance along sidewalks and driveways.

Amaryllis prolific in a Costa Rican yard

I visited a diversified coffee farm that was using Dracena (a common houseplant) as living fence posts in their vegetable garden. (And did I say coffee farm – nothing like drinking a farm fresh cup of coffee right on the farm).

Living Dracena fence posts at a Costa Rican coffee and vegetable farm

Tillandsia air plants were growing like weeds (which is basically what they are) on the trunks of trees.

These are all tropical plants that won’t survive in colder or drier climates of the US.  (The southern US states can grow more tropical stuff, but is is a small portion of the country.)

Many of the plants we grow both indoors and out here in the states come from different areas and grow differently in those areas than they do here.  Our vegetables come from all over the world.  So do our flowers and houseplants.

Plants from warmer areas either have to be grown indoors or as annuals even if they are perennial or evergreen in their native environments.

This is why the location of your garden, environment, and even the microclimate in your yard is important to know when selecting plants.  Aside from the difference of what can grow, plants grow much differently in Florida than they do in Minnesota or Virginia. And why it is important information when you’re asking questions about how to grow plants or control insects and diseases – because its all about location, location, location.

Bonus: Cashew apples!

 

Master Gardeners at a crossroads

{Warning. Today’s post is a rant. So I’ve illustrated it with pretty flowers in soothing colors to make it more palatable.)

Hydrangea

Anyone who gardens in the United States will be familiar with Master Gardeners. The Master Gardener program was started by Washington State University in 1971, when Extension agents in the largest urban counties found themselves overwhelmed with questions from the gardening public. These agents proposed training volunteers to help with educational outreach efforts, and with support from the university the first Master Gardener program was born. The history and function of Master Gardeners is further detailed in a couple of articles I co-authored (Chalker-Scott and Collman 2006 and Chalker-Scott and Tinnemore 2009): the more recent article also raises concerns about the decline of programmatic support in Washington state and elsewhere. If you’re a Master Gardener, the repercussions of this should alarm you.

Iris

What makes a successful Master Gardener? According to Sharon Collman, the last surviving founding agent of the WSU program, it begins with this:

  • A commitment to basic and advanced training program;
  • An open-minded approach to continuing education of themselves as well as others;
  • A willingness to provide science-based, unbiased information regardless of personal beliefs. (From Chalker-Scott and Collman, 2006)
    Pink fawn lily

    To be successful, volunteers need high-quality education consistently provided by university discipline experts. And that’s where the model is starting to fail in Washington state. Extension specialists who used to provide training to Master Gardeners in plant pathology, entomology, lawn and turf management, soil sciences, and other important fields have not been replaced by the university when they resign or retire.  More and more training is left to the devices of individual counties, whose Extension funding from WSU has been gutted over the decades. The previous university-centric approach to Master Gardener training has devolved into volunteer-driven county programs with little educational oversight.

Morning glory

While counties should be commended for keeping programming alive in the face of crippling budget cuts, the lack of meaningful curricular oversight by the university means that volunteers often don’t get the most current and relevant information pertaining to the science of gardening. Worse, they may be taken in by popular products and practices with no basis in science. Other volunteers may let their personal beliefs interfere with their pledge to provide objective, science-based information on topics including pesticides, GMOs, and other controversial topics. This undermines the credibility of the county program and ultimately the university who claims these volunteers.

Oregon oxalis

If you are a Master Gardener in Washington state or anywhere else in the U.S., it’s really incumbent upon YOU to insist that your land-grant university live up to its public outreach mission. You DESERVE access to Extension faculty specialists whose primary focus is to educate the gardening public.  The university takes credit for your volunteer hours when they make reports to the state legislature. Make them earn it.

Rose

Don’t waste your time contacting the university – you’ll get nothing but platitudes there. The place for change to start is with your elected state representatives.