As some of you know, my background is somewhat different from most faculty members in Horticulture in that my roots (no pun intended) are deepest in forestry. I’m sometimes asked to compare and contrast various aspects of horticulture and forestry. There are certainly differences – some of which I’ll get into in later posts – but there are also a lot of similarities. One of the truisms that seems to pervade both fields goes something like this: “When all else fails, blame the nursery”. Whenever a tree dies, whether it’s a 2-0 bare-root seedling or a tree that was spaded in with 60” tree space, the first reactions is “Must’ve been bad nursery stock”. Um, could it have been that the tree planting crew left the bundle of seedlings in the 90 degree sun all afternoon or that 5” caliper red oak really doesn’t belong in a bathtub? I bring this up because often we see suspicion, if not downright hostility, aimed at landscape nurseries. I thought of this as I was touring J. Frank Schmidt and Sons nursery this week near Boring, Oregon (yes, there really is town called Boring). J. Frank Schmidt and Sons is one of the largest wholesale producers of shade trees in the country. If you walk into virtually any garden in the northern half of the US, chances are you will see trees that began their life in the Schmidt’s fields under the shadow of Mt. Hood. J. Frank Schmidt nursery is among the most progressive nurseries in the industry, investing in new plant development, in-house research, and supporting university research through the J. Frank Schmidt Family Foundation and donating thousands of trees for research trials. During the tour, our host. Jim Ord, was excited to show us an air-slit container that Schmidt had developed for to reduce circling roots in container-grown trees. As I mentioned at the outset, we are often quick to blame nurseries for causing problems, here’s an example of a nursery working to solve problems. And this is just one example, Schmidt and other nurseries are working to develop and promote new elms and other species to provide a wider array of trees to replace ash trees in the wake of the Emerald Ash Borer. In some ways Schmidt is unique due its size and progressive stance but other ways it is very similar to a large majority of wholesale nurseries which with I interact. While there are certainly issues that trace their roots to problems in nursery production, most nurseries take great pride in their products and work constantly to refine and improve their growing techniques.
Author: Bert Cregg
Evaluating ‘Scientific’ Claims
Whenever I give talks to landscapers or gardening groups some of the most common questions that come up deal with various products promoted to provide ‘miracle’ results in the garden. These are usually various soil amendments; fertilizer additives, bio-stimulants, mycorrhizae, and the like. My initial reaction to these inquiries is, “What does your current basic plant maintenance look like?” Are you mulching? Irrigating when needed? Fertilizing if needed? Pruning properly? Have you matched the tree to the site conditions?
As a culture we seem oblivious to the tried and true and gravitate to the quick fix. Look at late-night infomercials for weight loss products. Hoards of people are willing to shell out $39.95 (plus shipping and handling) for a bottle of pills guaranteed to miraculously ‘melt away pounds’. Apparently “Eat less and exercise more” is a tougher sell. For garden products claiming to produce bigger, better plants there is sometimes a grain of scientific rationale and for a few, such as mycorrhizae, there are specific situations where they can be a benefit. Nevertheless the basic rule of caveat emptor is the best guide. Remember, just about anyone can get on PowerPoint and develop some slick looking 3-D bar charts and put together a glossy brochure or cool-looking website. Here are some things to consider when evaluating ‘scientific’ claims.
English 101
Words such as more, greater, bigger, faster are comparatives. They compare one thing to another. They need to be followed by a ‘than something’. Without an object they are meaningless. Advertisers use this all the time: “New Shill gasoline gives your car more power!” More power than what? Not putting any gas in your car at all? So what does a claim that a stimulant produces ‘more and stronger blossoms’ really mean?
What’s compared to what?
Some manufacturers go further and compare their product to an untreated control. This is a step in the right direction but can still be somewhat misleading. A common example is various bio-stimulant products, which often contain various enzymes and nutrient elements. Compared to an untreated control these may indeed improve plant growth. But is this due to a unique and patented blend of dung beetle excrement and papaya extract or simply the fact that a product contains essential plant nutrients? A better comparison would be to compare plants receiving the miracle product and plants receiving a conventional (and less expensive) fertilizer containing similar nutrient elements.
The bottom line, as always, is if something sounds too good to be true, it probably is. Before reaching for an exotic concoction of eye of newt and wing of bat, consider the basics of site selection and landscape plant management. Chances are there is a lot more to be gained from mundane matters such as putting the right tree in the right place than from trying to remedy the situation by sprinkling some magic dust over the roots.
Introducing Bert Cregg
Welcome to the Garden Professors. I am currently an Associate Professor and Extension Specialist in the Department of Horticulture and Department of Forestry at Michigan State University. I am also about the last person I thought would be doing a blog. I have often wondered who has time to read blogs, let alone write one. But I was intrigued when Jeff Gillman invited me to participate in this one. I have a lot of respect for Jeff and for Linda Chalker-Scott. Both have contributed a lot to landscape horticulture by critically examining the various myths that pervade gardening.
My background: I’m originally from the great Pacific Northwest; born and raised in Olympia, Washington. I was fortunate to go to Olympia High School, which offered courses in Botany, Ecology, and Forestry. Mr. Walt Chance, who taught Botany and Ecology, sparked my interest in plants and trees in particular. I got my B.S. in Forest Management from Washington State University and then did graduate work in tree physiology at Oklahoma State University (M.S. Forestry) and at the University of Georgia (Ph.D. Forest Resources). I began working on tree nursery and urban forestry-related issues with the USDA Forest Service and continued to research tree nursery issues as a scientist with Union Camp/International Paper. Since 1999 I have been on the faculty here are MSU developing research and extension programs that deal with landscape, nursery, and Christmas tree issues. I am currently involved in production issues related to container-grown trees and issues related to the Emerald Ash Borer outbreak. I also write and speak on landscape conifers. If you are interested in some of my research and professional publications you can wander over to my faculty web-page http://www.hrt.msu.edu/faculty/cregg.htm I live on a 5-acre farm in Dewitt, Michigan with my wife (Terri, whom I also met in Athens), our daughter (Hannah), two dogs, two horses, and an undetermined number of barn cats.
For my part, the theme of the blog follows Will Rogers’ famous line, “It’s not what we don’t know that causes us trouble, it’s what we know that ain’t so.” As Jeff and Linda have documented in their books and articles, there is a lot of science related to landscape horticulture that we choose to ignore. So, if you don’t like the facts getting in the way of a good story then this blog is probably not for you.
As we launch this blog, I’d like to add another quote from Will Rogers, the one he used to end every show. He stated simply, “I never a met a man I didn’t like.” The quote is remarkable because Rogers certainly met a lot of people that didn’t like him as he used his razor-sharp wit to carve up politicians and public figures of every stripe. But Rogers’ too-short life proved that we can disagree without being disagreeable; something sorely lacking in all forms of discourse these days. As we grope our way through the electronic age, many people hide behind the anonymity of the internet to spew all sorts of venom. By intent, this blog will touch on some controversial issues and we don’t expect readers to agree with everything we write. Our goal is to raise the level of dialogue about Horticulture; put some ‘meat’ and some science in the mix. This blog has a ‘comment’ bar and we encourage you will use it, but ask that we keep the focus on content not character.