Snow – should it stay or should it go?

It’s snowing here in Seattle – always a fun event, especially when we’re expecting up to 10 or more inches. I know…many of you laugh at our “big” snow, but the hilliness of Seattle makes driving in snow an adventure. (In fact, I’m supposed to be flying out tomorrow for a Connecticut presentation, and my flight’s already been cancelled and rebooked. Sigh.)

But what about the plants? This time of year people often ask whether they should leave the snow on their trees and shrubs. I covered this in December 2010 (and in a podcast in December 2011), but now I’ve come up with easily memorized advice:

If it’s light, leave it – if it’s heavy, heave it.

Light snow helps insulate trees and shrubs from winter dehydration, but heavy snow can permanently bend or worse, break, tree and shrub branches. Use a broom or rake to knock heavy snow off branches.

Bending is bad…

…but breaking is worse.

A dirty little secret

Like many, I was interested last week by the announcement that a University of Connecticut professor responsible for some of the research on resveratrol, a plant-based phenolic compound linked to various health benefits, had been accused of falsifying and fabricating data.  According to published reports, UConn officials found 145 cases of faked data that turned up in 26 published research articles by Dr. Depak Das.  Resveratrol occurs in many plants but most notably in grape skins and seeds, and one of the compounds associated with health benefits of red wine.

Needless to say, reports of Dr. Das’s wrongdoing were disappointing to those of us that enjoy an occasional glass of Caberbet Sauvignon or Merlot.  More importantly, although Dr. Das’s research was a relatively minor part of the resveratrol story, these types of reports invariably provide grist for the mill for those that like to question the motives and veracity of scientists.  Only Dr. Das can ultimately comment on his motivation for the con job.  Dr. Das is a tenured professor and head of his university’s Cardiovascular Research Center so presumably career advancement was not a primary factor in the ruse.

In theory, a well designed and well executed study that provides useful results should be publishable.  In reality, the adage that ‘it’s difficult to publish negative results’ often proves true.  I’m not familiar with Dr. Das’s studies or the data he’s reported to have faked, but suppose, for example, he had found that resveratrol did not reduce heart attack risk.  Assuming the trials were experimentally valid, there is still value in that knowledge; it could save others from conducting expensive but likely fruitless research or it may suggest other avenues of research.   Unfortunately, it’s often easier to publish positive results and use those data as the basis for future grant development.  I’m not privy to all the details at this juncture, but I wouldn’t be surprised if this started off as fudging a few numbers, which, in turn, formed the basis for other proposals and started a self perpetuating cycle.

As I noted, Dr. Das is an established scientist near the top of his game.  But the need to keep science clean extends to all levels.  In some regards, the pressure to fudge data is greatest at the entry level.  At research intensive universities, young assistant professors must generate enough grant funding and publications to secure tenure within six years of their hire.  Denial of tenure means time to hit the road.  Many universities are even opting to not reappoint some new faculty at the three-year mid-point review, which was often perceived as a ‘rubber stamp’ in the past.

Falsifying data in science is analogous to gambling in sports.  Both represent the ‘third rail’.  People wonder why baseball came down so hard on Pete Rose.  Once gambling is introduced in sports, fans assume the outcome is predetermined and the sport is done.  Likewise, science runs the risk of becoming irrelevant if the public assumes that researchers are only going to conclude whatever will get them published or help them land the next grant.  It sounds like UConn and the US Office of Research Integrity are preparing to throw the book at Dr. Das.  If he’s guilty as charged, they have to.

Noxious or not? A continuance of the Canada thistle discussion

Ray Eckhart, Master Gardener and loyal blog reader, wrote a long response to Alan’s request for research for the ongoing debate on Canada thistle started a few weeks ago by Jeff. Because he has a lot of links to research in his response, I thought it should have its own posting. So here’s Ray:

Here is a brief summary of the results of a google search of .edu and .gov or .us sites on the subject of Canada thistle or Cirsium arvense as a noxious weed, examining the “whys” by a mostly volunteer* Master Gardener reliant on published literature by reputable sources and charged with fulfilling the Land Grant University charter to bring science based information to the local level.

(* about $6500 of my annual salary and benefits comes from fulfilling Master Gardener responsibilities.)

From the Minnesota pdf referenced above:
“Noxious weeds are difficult to control and injurious to public health, the environment, roads, crops, livestock and property. By law, these weeds must be controlled on all public and private lands.”

From Montana:
“Canada thistle threatens productivity in both crop and non-croplands. In cropland, Canada thistle causes extensive yield losses through competition for light, nutrients, and moisture. It also increases harvesting problems due to seed and forage contamination. In Montana, it is estimated that two shoots per square yard can reduce wheat yield by 15 percent and 25 shoots per square yard can reduce wheat yield by 60 percent. Other Montana crops seriously threatened by Canada thistle include peas, corn, beans, alfalfa and sugar beets. Heavy infestations are also commonly found in overgrazed pastures and ranges and may crowd-out and replace native grasses and forbs, decreasing species diversity in an area.

“By 1795, Vermont enacted noxious weed legislation against Canada thistle and, in the early 1900’s, the currently named Noxious Weed Act gave a person the right to eradicate this species wherever they found it without fear of trespassing.

“In alfalfa stands grown for seed production, Canada thistle can reduce yield by 48 percent. An extra ten percent yield reduction can occur in alfalfa seed production due to seed cleaning. In pastures, Canada thistle reduces productivity by crowding out forage species with spiny leaves that deter cattle from grazing. In non-cropland ecosystems, Canada thistle can crowd out and replace native grasses and forbs limiting land’s recreational use. In gardens, flower beds, and lawns, Canada thistle’s extensive root system makes it a hassle to control. Mowing or pulling this weed is not effective because it grows again from vegetative buds on the roots. In fact, improper cultivation can even worsen Canada thistle problems!”

From Pennsylvania:
“In the Northeast, several weeds including bull and musk thistle, Canada thistle, purple loosestrife (Lythrum salicaria), mile-a-minute (Polygonum perfoliatum), and garlic mustard (Allaria petifolia) are receiving attention [for biological control efforts – ed.] because of their invasive nature.”

2nd Cite for Pennsylvania:
ECOLOGICAL THREAT: Natural communities that are threatened by Canada thistle include non-forested plant communities such as prairies, barrens, savannas, glades, sand dunes, fields and meadows that have been impacted by disturbance. As it establishes itself in an area, Canada thistle crowds out and replaces native plants, changes the structure and species composition of natural plant communities and reduces plant and animal diversity. This highly invasive thistle prevents the coexistence of other plant species through shading, competition for soil resources and possibly through the release of chemical toxins poisonous to other plants.

“Canada thistle is declared a “noxious weed” throughout the U.S. and has long been recognized as a major agricultural pest, costing tens of millions of dollars in direct crop losses annually and additional millions costs for control. Only recently have the harmful impacts of Canada thistle to native species and natural ecosystems received notable attention.”

“Some noxious or invasive weeds are highly toxic to equines, however, and can cause tremendous problems if allowed to invade horse pastures. This may be partially due to the extensive taproot in many broadleaf weeds that allow them to remain green longer into the dry season, thereby appearing potentially attractive to horses grazing in poor pastures. This list includes tansy ragwort, yellow starthistle, Russian knapweed, Canada thistle (Cirsium arvense), poison hemlocks, field bindweed, houndstongue, Scotchbroom (Cytisus scoparius), horsetails, leafy spurge, black henbane (Hyoscyamus niger), Klamath weed or St. Johnswort, kochia, yellow toadflax or butter-and-eggs (Linaria vulgaris), silverleaf nightshade (Solanum elaeagnifolium), and puncture vine.”

Colorado: “Canada thistle (Cirsium arvense) is an aggressive, creeping perennial weed that infests crops, pastures, rangeland, roadsides and noncrop areas. Generally, infestations start on disturbed ground, including ditch banks, overgrazed pastures, tilled fields or abandoned sites. Canada thistle reduces forage consumption in pastures and rangeland because cattle typically will not graze near infestations. In 2002, the Colorado Department of Agriculture surveyed counties and while incomplete, the results showed more than 100,000 acres infested with Canada thistle (Figure 1).”

2nd cite Colorado:
“Impacts Agricultural: Canada thistle is an aggressive, creeping, perennial weed. It infests crops, pastures, rangelands, roadsides, and riparian areas (Beck 1996).

“Ecological: Canada thistle spreads rapidly through horizontal roots, which give rise to shoots (Moore 1975). Its root system can be extensive, growing horizontally as much as 18 feet in one season (Nuzzo 1998). Most Canada thistle patches spread at a rate of 3-6 feet/year, crowding out more desirable species and creating thistle monocultures.

“Human: Spiny thickets of Canada thistle can restrict recreational access to infested areas.”

South Dakota:
“Noxious weeds are found in range and pasture as well as noncrop areas and cropland. Troublesome statewide noxious weeds like Canada thistle, leafy spurge, perennial sow thistle, Russian knapweed, and hoary cress can be serious problems in pasture and rangeland.”

“Weeds can reduce the quantity and the stand life of desirable forage plants in pastures and hayfields. These unwanted plants are often more aggressive than existing or desired forage species and compete for light, water, and nutrients. Weeds can also diminish the quality and palatability of the forage available for livestock grazing, and certain weed species are potentially poisonous to grazing animals. The aesthetic value of a pasture is also impacted by weeds.

“The state regulations of the Kentucky Seed Law classify certain plants such as Canada thistle, johnsongrass, and quackgrass as noxious weeds and prohibit their presence in commercial seed sold in Kentucky.”

National Park Service:
“Thistles are pioneer species and are most often found in sites where the ground cover has been disturbed by grazing, erosion, traffic, or other means. Thistles reduce the use of an area for grazing or recreational purposes because of the prominent spines on leaves, stalks, and blooms. Livestock do not eat thistles and will not graze between thistle plants on more desirable forage (Batra 1982).” (linked from .gov sites):
“THREATS POSED BY THIS SPECIES: Natural areas invaded by Cirsium arvense include prairies and other grasslands in the midwest and Great Plains and riparian areas in the intermountain west. Cirsium arvense threatens natural communities by directly competing with and displacing native vegetation, decreasing species diversity, and changing the structure and composition of some habitats. Species diversity in an “undisturbed” Colorado grassland was inversely proportional to the relative frequency of Canada thistle (Stachion and Zimdahl 1980). Canada thistle invades natural communities primarily through vegetative expansion, and secondarily through seedling establishment. Cirsium arvense presents an economic threat to farmers and ranchers. Infestations reduce crop yield through competition for water, nutrients and minerals (Malicki and Berbeciowa 1986) and interfere with harvest (Boldt 1981). In Canada, the major impact of Cirsium arvense is in agricultural land, and in natural areas that have been disturbed or are undergoing restoration (White et al. 1993). In the U.S., it is a host for bean aphid and stalk borer, insects that affect corn and tomatoes (Moore 1975), and for sod-web worm (Crampus sp.) which damages corn (Detmers 1927). In Bulgaria Cirsium arvense is a host for the cucumber mosaic virus (Dikova 1989). In addition to reducing forage and pasture production, Canada thistle may scratch grazing animals, resulting in small infections (Moore 1975).”

Washington State:
“Why is it a noxious weed? Once established, it spreads quickly replacing native plants. It grows in circular patches, spreading vegetatively through roots which can spread 10 -12′ in one season. It poses an economic threat to the agriculture industry by reducing crop yields.”

“Threats: Canada thistle’s rapid growth aggressively competes with native plants and crops for nutrients, moisture and light. It releases chemicals toxic to other plants. The result is a loss of natural diversity. It is known to harbor other pest species, e.g., insects, and has long been recognized as an agricultural est. Both natural and human caused disturbances can create the opportunity for Canada thistle to become established in natural communities.”

“PROBLEM: The extensive root system of Canada thistle allows it to out-compete and displace many native species, especially in degraded prairies where native species are not well established. Spreading both by seed and rhizome, Canada thistle can create monocultures covering large areas. The wind-dispersed seeds may remain viable for 20 years or more, allowing it to spread quickly and making it difficult to eradicate.”

There are more, but I stopped on page 3 of the 120 page result of the google .edu search. I’ll leave it to others more qualified than I am to further debate the relative merits of why or why not a more cavalier (heh!) approach other than current government regulatory action is or is not warranted.

Eco Plant Pals?

Last Monday a friend of mine stopped by the office and dropped off a couple of plant "kits" for my kids.  I didn’t spend much time looking at them at first, but I brought them out that night when I got home to show to the family and…they’re really neat!  Called Eco Plant Pals, these little kits include a container, some media, and some seeds for one of 18 different plants.  Each of these plants has their own names, like Chris Catnip for (you guessed it) a catnip plant and Laura Lobelia.  It’s all about the marketing with cute pictures and names.  See all of the cute kits here.

 I’ll tell you right from the start that they cost too much (retail anyway), but they’re cute, and the girls are excited to plant them, so what can I say?  I believe that anything that gets kids excited about planting is a good thing.  Everything in the kit is biodegradable which is nice.  I do have one complaint though.  Not a huge one, but one worth mentioning all the same.  Plant number 18 is Butterfly Beth and it’s a butterfly bush.  As many of you know I absolutely love butterfly bush, but I am also aware that in certain parts of the country this shrub is considered an invasive plant.  While all of the other plants are, as far as I can tell, pretty benign (most are annuals — there is a Robert Redwood though!) I have to question calling Butterfly Beth a good choice ecologically.

Yes, she’s an invasive, but isn’t she cute!

Name This Course

Undergraduate enrollment in the Virginia Tech Horticulture program has fluctuated over the years.  The late 70’s saw huge numbers of students interested in all things green and growing – nearly 300. There was a gentle decline through the 80’s and in the 90’s number held around 150. A sharper decline took place over the past 8 years, with enrollment bottoming out at 85 students in 2009. Things have picked up a bit since – we’re currently at 100 give or take a few.  But we really, really need to bump it back up to 150+ or we risk getting combined/rolled into a broader plant science program.

Fewer than half of our students start out as Hort majors their freshman year; the larger portion are transfer students, either from community college programs or internal transfers from within the university. 

A couple of our lower-level courses are what we refer to as “gateway” classes that lead to these internal transfers to our department.  Indoor Plants is a biggie –  anyone can take it as a free elective, and many students get hooked on hort as they learn some basics of identification, care, and propagation.  Floral Design is wildly popular and fills up instantly; credits earned counts toward a university-wide “core” requirement for “creativity and aesthetics.”  Something these classes have in common is the hands-on aspect, plus the student gets to take something back to the dorm or apartment, be it a terrarium or floral arrangement. 

I am in the process of developing a new course which will hopefully serve as a third “gateway” class – an introduction to gardening.

Food and flowers, digging in the dirt, all that great stuff.  I want it to be fun and exciting, not filled with do’s and don’ts.  The kind of class that will spark an interest or set off a light bulb. Or perhaps inspire them to transfer to Horticulture. This generation of undergrads (mostly young people from 18 to 22) is tough to impress. They’re glued to their smartphones, and if I’m not mistaken, attention spans aren’t quite what they used to be.  But I believe I can frame the fabulously broad and deep topic of gardening into something personal, immediate, and enjoyable. 

What I need to further this mission is a NAME for the course.  It can’t be too obscure; someone flipping through the course listings should be able to decipher class content from the title (best name ever for a university class: Magical Mushrooms and Mysterious Molds taught by plant pathologist/legend Dr. George Hudler at Cornell University). 

My working name for the course has been “Successful Gardening.”  Yawn.  "Sustainable Gardening" is also a possibility, but every department in Agriculture/Life Sciences (and beyond) is slapping "Sustainable [whatever] onto new courses. Though that may be the ticket for the immediate future.

Please, dear reader, put on your creative thinking cap and help me come up with something better!

What I did on my Christmas vacation

The week between Christmas and New Years’ is usually pretty laid back around here.  But not this time!  Along with 22 volunteers, 3 family members, and 1 graduate student, I spent that week putting in 80 trees for a long-term experiment.

My long-suffering family and I installing the last of the 80 trees on the fourth day of hell.

My intrepid graduate student Cindy Riskin obtained 40 B&B Japanese maple (Acer palmatum) and 40 containerized mugo pine (Pinus mugo).  Half of each of the trees were installed conventionally, meaning the root balls were not significantly disturbed, and half were bare-rooted by root-washing methods I’ve discussed on the blog previously. Roots that circled or had other flaws were pruned as needed. Over the next several years, we’ll be assessing tree health and comparing the two root preparation techniques in terms of tree establishment.

Installed maple

Installed pine

Look at some of the surprises we uncovered during root preparation!  I will say unequivocally that these were the WORST quality trees I’ve ever seen coming out of a nursery.  And they weren’t cheap.

Yes, that’s a 4" pot still covering the roots inside this "gallon" mugo pine.

The duct tape is where the top of the burlap was in the original B&B.  Every one of the B&B trees we bare-rooted was buried too deeply in the clay and burlap.

Multiple trees?  Multiple messes!

Stay tuned for more…

The fun and the not so fun

Just a quick post today.  Today is the second Monday in January which means: 1) classes resume here at MSU and 2) it’s the first day of the Great lakes Trade EXPO in Grand Rapids, which is sponsored by the Michigan Nursery and Landscape Association and Michigan Turf Foundation.  I’m on tap for two presentations this afternoon.  

The first one is a bit of post-mortem on the Imprelis issue that dominated some of our lives back in the summer.  My talk, "Imprelis: What went wrong?’ looks back over the development of the Imprelis debacle.  The final verdict on how the EPA allowed the registration on an herbicide with such devastating non-target effects probably won’t be fully known until the dust settles on the legal process. Bottom line: the testing that was done was not adequate and either DuPont or the EPA (or both) dropped the ball.

My second talk, thankfully, is a little more upbeat.  In "Little Big Men" I discuss the use of miniature and dwarf conifers for landscaping.  I even get to talk about one of my new interests: railway gardening.  I haven’t taken the plunge yet – not enough time or nearly enough money – but I think I may have found a hobby for retirement.  For those that have access to the Oregon Association of Nurseries Digger magazine, Elizabeth Peterson wrote a very nice feature on railway gardens in their September issue.
Courtesy: Elizabeth Peterson