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This ‘n That

Grading finals, looking at roots, and planting seeds is consuming my time this spring, but I have just a few things to share today which might be interesting.

So, as those of you who follow this blog know, I love peanuts. This year we’re planting out a bunch of new varieties, a few of which are extremely interesting. Believe it or not there are not only red and pink peanuts but also black, white, and mottled peanuts. We have these on order — when they come in I’ll post a picture. When we introduce Minnesota Boiled Peanuts at the State Fair in a few years (that’s the goal anyway) the plan is to introduce a wide variety of really unique looking peanuts. Fingers crossed they can live here!

Here, at the University of Minnesota, we do a really great job of telling people that, when they fertilize their grass, they should keep the fertilizer on the grass and not on the sidewalk — SO WHY CAN’T THE UNIVERSITY TEACH THE KIDS WHO APPLY THE FERTILIZER TO THE UNIVERSITY’S LAWNS TO KEEP THE DARN FERTILIZER OFF OF THE PAVEMENT?!? Last week as I walked in I heard a crunching sound coming from my feet. When I looked down there was a little pile of fertilizer on the sidewalk.

Believe it or not, judiciously fertilizing your grass actually helps prevent fertilizer run-off. That’s because grass with a weak root system (as occurs in the typical lawn when you don’t fertilize at all) won’t be able to hold the soil as well — so you get more erosion. So do fertilize your lawn, just don’t go nuts.

About that whole tree in the lung thing which I posted last week? Yeah — It’s BS. How do we know it’s BS? No obvious roots on the tree and the tree’s needles were green (you don’t get green plants without sunlight). Personally I think this is some kind of odd cry for attention, but I guess it’s possible that the guy swallowed a cutting while he was shearing/pruning trees. HOWEVER, there are documented cases where seeds will germinate in a persons lung — Usually the person has a compromised immune system.

These are a few of my (least) favorite things…

Spring clean-up came in earnest this weekend at Daisy Hill farm. Everything will be downhill from here as my least favorite yard chore; cutting back our ornamental grasses, is done for the year. I know, I know, there are all kinds of shortcuts and tricks for this job including lassoing grasses for the last round-up (see Holly’s March 8 post), duct-taping them, and cutting them down with hedge-trimmers or a chainsaw. Unfortunately, between our winter snow beating them down and our dogs using them as their own personal jungle playground, standing the grasses up neatly to await a trim just isn’t an option. So I dive in and do it the old-fashion way; armed with a set of hand-loppers, every piece of personal protective equipment I can find, and the entire repertoire of swear words my Army sergeant Old Man taught me. Between hacking, cussing, and hauling it’s a two afternoon job. On the plus side, it did give me time to ponder my top five list of least favorite yard jobs. See how it compares with your list…

Cutting back ornamental grasses
Picking up black walnuts (this is to Fall what no. 1 is to spring)
Weeding (the only redeeming factor is instant gratification)
Deadheading (yeah, it’s not the hard but you know you’ll have to turn right around and do it again (and again and again…)
Leaf raking (Actually, this wouldn’t be so bad but I went out and bought a chipper-shredder a couple years ago and feel compelled to use it. Works like a champ – shreds leaves as fast as I can feed them in. Too bad the bag needs to be emptied approximately every 43 seconds…)

What to do when it’s still raining?

It’s almost May…and it’s still raining. Even for our normally wet spring climate, this has been an unusually soggy year. I’m also blaming the weather on my 3rd or 4th cold so far this year, which has knocked me flat for the last 6 days (which was why I had no Friday puzzle posted). So in between blowing my nose, hacking my lungs out, and generally feeling sorry for myself, I started looking over 10 years’ worth of photos of our home landscape.

You’ve seen bits and pieces of this before in some of my postings. But one of the spots I’m most proud of is the tiny east-facing side yard that originally contained lawn, a lilac, and a border of arborvitae. Within the first few years the lawn came out and plants started going in. In 2004 I’d installed some small rhododendron, a redbud (left foreground), and a whole lot of woodchips:

Since then we removed the lilac (it had been planted too close to the garage and was a powdery mildew magnet), put in an arbor and wisteria (on the right), and added a few more plants (ferns, bleeding hearts, various bulbs and tubers, etc.). Here it is two (2006) and five (2009) years later:

This year we’ll finish off the area with some flagstone pavers.

One of the main reasons I’m so pleased with this area is that it was inexpensive to redo and it established quickly. We bought the redbud, the wisteria, and the bulbs, but the rest were donations from friends’ gardens, or volunteers that popped up elsewhere in the yard, or plants that someone else wanted removed (like the larger rhody in the far left corner and the dogwood in the right foreground, 2006 photo). The chips were free; the flagstones were a major score from craigslist (free to whomever would pry them up and lug them out). All the purchased trees and shrubs were barerooted; and root-pruned if needed before planting. Upkeep is minimal except for a bit of pruning and spot watering during the hottest summer months; we’ve lost no plants other than the occasional bulb poaching by squirrels.

It’s just a little bitty sideyard…but I enjoy walking through it every time I’m outside, even in the rain.

Who you gonna call?

As I noted last week, this has been a long winter in Michigan – OK, Jeff, no chortling from the frozen tundra of Minnesota… Most gardeners in this area have only been able to do their spring yard and garden clean-ups in fits and starts as the weather allows. We’re finally warming up a bit this week but now strong storms are in the forecast. One of the things gardeners will want to do is to size up any winter damage that has occurred since they put things to bed last fall. Although our winter was long, it was otherwise unremarkable with few temperature extremes – low or high – that would likely cause problems. In fact, aside from some heavy snow in February, the winter of 2010-11 was probably the closest thing we’ve had to a ‘normal’ winter in the 11 years I’ve lived in Michigan. Nevertheless, we will still be taking numerous extension calls on what we would consider ‘typical’ winter damage to trees and shrubs.

In this neighborhood not too far from my house, deer have declared open season on arborvitae.

One of the biggest issues we face is wildlife damage. The two biggest sources of problems are small mammals and deer. Small mammals such as mice, rabbits, squirrels and voles cause damage mainly by gnawing on trunks and branches. Despite their small size, these animals can kill trees by removing bark and underlying tissue around the circumference of a tree trunk, a process referred to as ‘girdling’. If a large portion of trunk circumference has been girdled, trees are unable to move energy reserves between roots and shoots, and will eventually die. Deer can cause extensive damage to trees and shrubs due to feeding and also through rubbing their antlers. Deer feeding is often indicated by a ‘browse line’ based on how high deer can reach. Rub damage from deer antlers can cause major deformation to trunks and can even kill trees by girdling. I was in a new subdivision in the East Lansing area this weekend and well over half of the trees on the tree lawns will need to be replaced due to extensive deer rub damage.

At least half of the trees in this entire subdivision will need to be replaced due to deer-rub damage.

Dealing with wildlife damage is a complex issue and varies with local conditions and wildlife pressure. Fortunately, wildlife experts from several universities (Cornell, Clemson, Nebraska, Utah State) have organized the Internet Center for Wildlife Damage Management. http://icwdm.org/ This site is one of the best resources I have run across for assessing and dealing with wildlife damage issues. If you’re in a position where you have to deal with wildlife damage or advise clients about damage, this is a useful site to add to your bookmarks.

Invasive plants, politics and science

I’ve had a hectic week (taxes! financial aid!) and haven’t had a chance to think about posting. Fortunately, yet another colleague just sent me an interesting link that’s worth sharing and discussing.

For those of you who aren’t familiar with how Master Gardener programs work, they are built on volunteers who receive training in garden-related sciences and then contribute a significant number of hours to outreach education. Many MGs work in plant clinics, and others volunteer in public gardens. Regardless of where they spend their volunteer hours, they are always representing their sponsoring university and therefore dispense advice and follow practices based on the best available science.

This will help explain why the Master Gardeners who volunteered at the Racine Zoo felt they had to resign their volunteer positions.

(Note that the zoo is losing out on 1300+ hours/year of donated garden upkeep, but the zoo president and CEO is confident that the zoo staff can pick that up. Wonder if he’ll be out there weeding and watering?)

Interesting and useful web site about invasive insect pests

Just heard about this from a colleague. This website has a link to a great image gallery of exotic insect pests. Though it’s primarily geared towards forest pests, the urban forest is just as susceptible.

Invasion of the killer earthworms

It sounds like a B-grade horror movie. Millions of earthworms, moving silently beneath soil, wreaking havoc until the entire planet is uninhabitable. Sound a little far-fetched? Not to ecologists that study northern hardwood forests. While most of us grew up thinking earthworms were ubiquitous, turns out they are not native in parts of North America that were covered with ice during the last glacial period. Most of us also grew up thinking that earthworms where the good guys/girls (they’re hermaphroditic), churning up compacted soil and leaving nutrient-rich castings behind. In many northern hardwood forests, however, exotic earthworms, have become invasive and ecologists believe they are having profound effect on ecosystems.

I have to admit I hadn’t paid that much attention to the invasive earthworm issue but I attended a seminar last week by Dr. Lee Frelich, Director of the Center for Forest Ecology at the University of Minnesota. Dr. Frelich’s seminar touched on several areas of research, almost all of it extremely depressing, related to climate change and invasive species. He and his colleagues have documented significant changes in soil ecosystem processes and plant succession associated with increasing populations of earthworms. Nightcrawlers, in particular, cause a lot of problems because they consume fresh leaf litter causing it to decompose at a much faster rate compared to un-invaded ecosystems. The net result of these soil changes is that few trees or shrubs can reproduce in the understory. Over time this may lead to a very different looking forest than exists there today.

Of course, we may end up with a very different forest in any event, given some of the climate change scenarios Dr. Frelich presented. One worst-case model predicted the climate of the Boundary Waters area of Minnesota would resemble that of present-day Oklahoma City by the end of the century. But I try not to worry; I figure by that point I’ll be food for the earthworms anyway.

For more info on the earthworms that ate Minnesota, check out these links, if you dare…

http://www.scientificamerican.com/article.cfm?id=invasive-earthworms-denude-forests

http://www.dnr.state.mn.us/invasives/terrestrialanimals/earthworms/index.html

California Flower, Food and Garden Show

I’m giving two talks at the California Flower, Food and Garden Show in Sacramento today and tomorrow: details are linked here. It would be great to meet some of our California readers in person if you plan on being there.

I’ll try to take some photos and share my thoughts about the show on upcoming posts. Maybe I’ll even find my Friday quiz topic lurking there!

Rain barrels

A few weeks ago one of our readers, landscape architect Owen Dell, sent me a link to his blog where he takes on rain barrels. It’s a great analysis of the (im)practicalities of rain barrels and it got me to wondering how many of our readers (and my GP colleagues) use these as supplemental sources of irrigation water?

I have two in our back yard that were made from old olive oil containers retrofitted for collecting and dispensing water. They’re hooked together so that when one fills, the rain is diverted to the second.

We use this water pretty much for watering container plants, especially those on our south-facing front porch that require watering every other day during the summer. The barrels each hold 55 gallons and are always full during the winter and spring. We drain them almost dry over the summer, but even a brief rain results in several gallons collected.

So I think they’re a pretty good deal, since we use relatively little water from the hose to keep our container plants happy. But Owen brings up some valid points in his analysis, as do commenters on his blog.

What do you all think?

Is local always better?

As those that have followed the blog for awhile are aware, among my pet peeves are some of the naïve statements that are repeated ad nauseam by proponents of native plants for landscaping. You know the usual litany: natives don’t need water, don’t need fertilizer, resistant to insects, resistant to diseases, yada, yada… According to the dogma, native plants possess these traits because they’ve evolved here and they belong here. I hasten to point out; I have nothing against natives and think we ought to plant more of them whenever they are an appropriate choice. The problem, of course, with the typical native company line is that these statements are so obviously nonsensical they undermine the credibility of native plant advocates. Adaptations to resist environmental stress, for example, are a function natural selection and evolution. There are lots of droughty environments in the world; why should we assume that only local plants will be adapted to drought? Then there is the obvious problem of disturbed environments. Why should we assume that trees that have evolved in native woodlands will be good street trees? In fact, often they’re not.

Torryea taxifolia

But a new and potentially contentious argument is emerging in the ‘Is native better?’ discussion: Assisted migration. The basic premise of assisted migration (also referred to as assisted colonization) is that climate is changing faster than many organisms, especially long-lived organisms like trees, can evolve. Therefore to prevent species extinctions we should pro-actively move species (typically northward in the Northern hemisphere) so they will be in a better place as the world gets warmer. Sound far-fetched? Some of this is already occurring. In Florida a group called the Torreya Guardians has already taken it upon themselves to establish populations of a threatened conifer, Torreya taxifolia, in the southern Appalachians, outside of its native range in the panhandle of Florida. http://www.torreyaguardians.org/ In British Columbia, the provincial forest service is beginning to incorporate climate change scenarios into its tree improvement and development plans; trying to identify seed sources and species adapted to climates predicted throughout the 21^st century.http://www.msnbc.msn.com/id/32012170/ns/us_news-environment/

Is local better? Foresters often see significant growth gains by moving seed sources northward. Will climate change increase this effect?

Clearly assisted migration is a controversial topic fraught with all kinds of uncertainties. Is climate really changing? How fast will it change? What about unintended consequences? Could the assisted species out-compete a local species that would’ve been OK otherwise? And then there are those who might wonder aloud about the hypocrisy of embracing species movements when they’re done by conservation biologists but not by horticulturists.