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The Botany of Syrup

Categories: Midd Blogosphere

Any kid will tell you maple syrup is special, but how special? Is tapping a maple tree like putting a spigot in the trunk? And why maple?

In a wonderful book I’ve written about before by Nalini M. Nadkarni called “Between Earth and Sky-Our Intimate Connection to Trees” she writes of how botanists and tree physiologists have been looking at how sap is produced within maple in the last couple of decades. Like many things, the wild world of maple syrup seems like a freak chance, a perfect random combination of physiology.

A tree’s goal, aside from reproduction, is to feed itself-it’s tough being an autotroph, and a whole lot of work. Photosynthesis takes place all summer long, making sugars for respiration, growth, reproduction, and a little extra. This extra, in a sugar maple, gets stored as starches within the sapwood of the tree. The sapwood, as the name sounds, is the area of the trunk and branches where water and sugars move around, located within the first couple rings of the wood.

As my winter term class hopefully remembers, Sugar maple is one of our “live slow, die old” species of trees. These trees are more shade tolerant, in life for the long haul, and have the foresight to save extra sugar for lean times, such as the introduction of shade or competition. Other tree species, such as Poplar, live fast and die young, and burn through all their sugar like a hyper 3 old, just as prone to growth spurts as an Aspen in the spring.

Early spring brings sun, a little higher in the sky, and better able to warm. Cats in our house know this, moving away from the woodstove and into little patches of sunlight on soft surfaces. Trees know this too, as the sun warms the bark and the wood. The air may be below freezing, but tree surfaces and interiors could be well above freezing. Once the wood gets to be above 40 degrees, enzymes turn these stored starches into sugars, mostly sucrose, and the sugar is now within the sap. This explains the magical sugaring temperature of 40, any warmer and this process stops.

The other freak chance miracle of maple is getting the sap flowing out of the tree. Not all trees can do this. Water is moved throughout the xylem of the tree by capillary action and transpiration, meaning the leaves need to be on the tree for water to move very effectively. That  would ordinarily make for tough sugaring in March and April, except in Maple.

In maple trees the space around the wood fibers is filled with gas, not water like most plants. When the temperature drops, this gas contracts, making space for the sap laden with sugar in between the cells. So water can move upwards from the roots by capillary action without the benefit of transpiration from leaves. This water freezes at night between the cells.

The day brings warm temperatures, melting this ice and expanding the gas, forcing water down the branches into the stems and trunks of the tree. The taps put into tree trunks to collect sap pierce the xylem all this sap is moving through, and water flows down the tap into the bucket or plastic line.

Interested biology students should read another blog, The Botanist in the Kitchen, http://botanistinthekitchen.wordpress.com/2013/03/18/maple-syrup-mechanics/ , and a cool roadtrip would be the Proctor Maple Research Facility of my old school UVM.

 

The Butternut Seed Orchard

Categories: Midd Blogosphere

I’ve learned this summer a wonderful way to get attention is to build a one acre, 8′ high deer exclusion fence out on South Street past Eastview, brush hog down the existing corn, and not tell anyone what we are doing.

The landscape department, working with the State of Vermont, the US Forest Service, and a local researcher from UVM (Dale Bergdahl, father in law to local Middlebury College hero Mike Kiernan) applied for and received a grant from the Vermont Department of Forest, Parks and Recreation to erect the fence to grow Butternut trees. Butternut is threatened by Butternut Canker, a fungus with the potential to wipe out all Butternut across the United States. When found, disease resistant trees are grafted and grown for seed. An orchard was already established in Brandon, but another in a different locale (geographical as well as horticultural) is always preferred.

Deer love young butternut trees, hence the fence.

I’ve written a large explanation on the project on the blog here, it’s an entire page-Butternut Seed Orchard. I should give profuse thanks to Barbara Schultz, the forest health program manager in the Vermont Dept. of Forests, Parks and Recreation for an immense amount of work to make it possible,  Chris Casey  of the US Forest Service and Tom Simmons of the Vermont Dept. of FPR. And also, most importantly, local volunteer Sally Thodal for helping plant Butternut trees on one of the hottest days of the year.

Feel free to email any questions you have, and say hi to the trees as you drive by.

Cultivating Hope, Wisdom, Compassion, and a Tree

Categories: Midd Blogosphere

Nature can teach us many things. Life, death, love. And Hope, Wisdom, and Compassion. How appropriate the 14th Dalai Lama uses ‘cultivating’, the act of promoting growth, to describe his wish for the dissemination of his main tenants for the human race to strive for.

Sogyal Rinpoche, the Buddist author of the Tibetan Book of Living and Dying, writes of trees:

Think of a tree. When you think of a tree, you tend to think of a distinctly defined object. But when you look at it more closely, you will see that it has no independent existence. When you contemplate it, you will find that it dissolves into an extremely subtle net of relationships that stretch across the universe. The rain that falls on its leaves, the wind that sways it, the soil that nourishes and sustains it all the seasons form part of the tree. As you think about the tree more and more you will discover that everything in the universe helps make the tree what it is; that it cannot be isolated from anything else and at every moment its nature is subtly changing.

A Bur Oak is planted next to the Garden of the Seasons just south of the main library, waiting to be blessed by His Holiness the Dalai Lama. Think about this tree, as it grows tall and wide, its roots spreading far across the quad joining its companions, and be reminded that like a tree, we all depend upon each other as well: we all share a subtle net of relationships. Let the small oak show our hope, our faith in growth and long life, as our grandchildren will see the large tree. And let it teach us wisdom, like the timeless ‘wise old oak’ of our childhood stories, and learn from it compassion, as no tree stands alone.

Bur Oak by the Garden of the Seasons

Watering

Categories: Midd Blogosphere

Pick up any plant biology book, and they consistently list the three macro nutrients all plants need as N, P, and K, the chemical symbols for Nitrogen, Potassium, and Phosphorus. But really, what we share with plants is a need for ‘macro’ macro nutrients, something so profoundly necessary that the books don’t even feel the need to list them, and they form the backbone of all life. We’re talking about C, H, and O, or Carbon, Hydrogen, and Oxygen.

The carbon and the oxygen are easy, the plants are getting that in the air we breathe. It’s the Hydrogen that’s been stressing me out lately. Plants obtain it solely from water, through photosynthesis. I always remember my snide remarks in the retail garden center world, when a customer would ask me what kind of fertilizer to buy with their new purchases. For the most part, I’d tell them the single greatest thing they could do would be to water.

How much? It’s a good question with no real definitive answer. I remember from who knows where that gardens in the northeast need about 1/2″ of rain a week in the growing season, and an article on strawberry production I found says about the same (actually .63″). Trees need quite a bit more, though, as they have much more extensive roots throughout the soil horizon. Plan on 2″ of rain a week. I found a handy online calculator to do the math, but here’s a quick answer. A newly planted tree with about a 2″ trunk, should have a 5′ x 5′ zone watered around it, so that’s about 30 gallons, pretending to be a 2″ rain.

Sounds a little high, but the wild and woolly world of plants is never easy.  Last year we were averaging 4″ of rain a month, and we didn’t have to do any supplemental watering. On cloudy days plants don’t transpire, or lose water, at as great a clip, so maybe last year it was fine.

Or not. We’re running around like chickens with our heads cut off right now, watering every tree we’ve planted for the last 3 years. (that’s a lot) All of our recently planted trees are showing drought stress, and I’m wondering if I hadn’t watered enough in the last 2 wet years to well establish the trees. When watering, it is best to water a lot all at once, so that the roots have ample moisture and can grow long and deep. Too little water, and the tree keeps its roots near the surface, where the water is, and this makes it less drought resistant in the long run.

Gator Bags for Watering

We water all trees with 40-50 gallons of water about every 2 weeks. We use two gator bags zipped together, and they drain over the course of about a day. We hand water any tree we missed, and then gator bag it. In this heat and drought, I’d like to water weekly, but I’ve been checking the ground around the trees, and I think we’re keeping up.

Another good trick I learned once when hand watering is to watch the ground as it absorbs water from the hose. I think this is the one of the Eliot Coleman gardening books, but I loaned my copy out and now it’s gone. Once the ground starts to get saturated, the top gets glossy. Take the hose off that spot, and the glossiness will disappear. If you can count to 3 before the glossiness is gone, the ground is moist enough.

Drought stress symptoms in Birch

identifying drought stress in plants can be tricky, especially in herbaceous plants like annuals and perennials. Woody plants are easier. The inner leaves of the tree turn yellow and fall off. I find this remarkable. It isn’t like trees have brains, but here they are smart enough to drop the inner, less efficient leaves, to conserve its precious water for the maximally producing outer leaves. By the time your plants are showing symptoms of drought, obviously much damage is done. Plants are pretty hardy, so even with serious problems the tree will probably be fine.

Season Creep

Categories: Midd Blogosphere

Everybody has their own phenologies, their own timing of spring. First day the snow shovels get put away (unused in my driveway at all this year, I might add), first day of working without long johns on, or maybe the first day of wearing shorts. I’ve always dreamed as a horticulturist of keeping a journal, tracking of events throughout the years such as first frost, peepers in the pond, first robin at the feeder. Yesterday I realized I sorta had one, and that I hadn’t posted to it in a while. So here I am…

One of my harbingers of spring is the opening of forsythia. It’s a plant I grew up with in our backyard, and the bright yellow flowers more than anything else speak spring to my weary winter frame. After arriving to work yesterday I saw the ‘Vermont Sun’ Forsythia in bloom next to the service building parking lot. Early. I first wrote about this hedge of Forsythia when in bloom on April 13, 2009, and wrote about it again in 2010 when it way 11 days earlier in bloom, on April 4. For the record, the bloom date this year was yesterday, March 20. Peepers were in my pond Monday the 19th of March, a blog post on them in 2010 was April 2.

Phenology, not brought to you by the letter “F”, comes from the greek phaino, meaning to show or appear. It’s the study of recurring life cycles of what is around us, the timing of insects, plants, mammals, and the relationship of time to weather and climate. There is even a USA National Phenology Network, using volunteers across the nation to study these cycles. A great example is the Cloned Plants Project, a partnership with the aforementioned  USA NPN and the National Weather Service, where clones of either a lilac or flowering dogwood are planted in an observer’s yard and bloom times noted throughout the years.

Obviously, this is wonderful data for global warming. More inputs than air temperature factor into when trees leaf out in the spring. Daylength certainly plays a part, as well as moisture conditions the previous fall, and amount of cold temperatures in the winter. But air temperature is the biggie. A study of oak leaf emergence in England since 1947 has indicated that a 1 degree rise in global temperature is associated with a 7 day earlier tree leafing. This is called Season Creep, and scientists point to this as one of the first effects of global warming that we can actually see in the present, with most of the other detrimental effects taking place in the future.

So where does this put us right now? I’ve been getting many questions on if this early spring will hurt the trees or landscape, and the best answer isn’t cut and dry. The worry is a late frost or freeze after the buds have opened, or shoots emerged from the ground. Short answer? The plants will be fine.Trees losing their first set of leaves can regrow new ones from secondary buds. Like beer on a worknight, it isn’t something to make a habit, but once in a while it isn’t going to hurt anything. And bulbs and perennials emerging from the ground know just when it is safe to come out-a frost never seems to bother them.

The impact of a freeze will be bad for us humans. For example, apples bloom before the leaves emerge, so should they bloom and get pollinated, a late freeze will destroy most of the crop for the year. There are no secondary buds for flowers.

The mild and early spring will cause other problems as well. Those suffering from allergies are miserable all the sooner. And the short, mild winter did nothing to mitigate the deer tick population, so extra care should be taken. If you are interested in tracking the spring and summer phenologically, I can’t speak highly enough of the UMass Landscape Message, posted weekly.

No-Mow at Richard Stockton

Categories: Midd Blogosphere

I recently received an email from Jessica Okazaki, from the Richard Stockton College of New Jersey, asking about Middlebury’s no-mow program. She is interested in starting a similar project at her school. Read more at her Facebook group called “Lose the Lawn”. I’m sure she isn’t the only one thinking about this on a college campus, so I thought that rather than just responding to her alone I would turn the answers into a blog post. A couple of her questions are below.

 For my project, I am hoping to plant native plants to this pinelands region, (or even better -native endangered/threatened species if they can grow on this soil). In some areas, I think I would like native grass, similar to lawn but needs no mowing… so that the students can walk on them without killing the plants… if that’s possible…..

 I would like your tips / advice on how to prepare the right soil for native plants and some specific plants you might recommend.

 I’ll speak first about the sites you have in mind, and keep in mind I’m looking at this from 300+ miles away, and don’t know much about the Pine Barrens. Your master plan is an excellent document, and has some great insights into your landscape in general.

Middlebury College and Richard Stockton seem to have drastically different landscapes, not only ecologically but from a human standpoint as well. Your beautiful campus is considerably more condensed, surrounded by woods (at least according to Google Maps). Here at Middlebury we have a relatively large but spread out campus. Many of our no-mow zones are many acres in size, while some of the areas you have in mind look quite a bit smaller.

Our no-mow zones are simply that-areas where we have let the lawn go. Native and non-native wildflowers are infiltrating the areas, and we are achieving a nice effect of contrast between mown lawn and no-mow, helping to differentiate sections of our campus. Because of their size, we couldn’t possibly think about re-landscaping these areas with plants, or even reseeding. It would be nice to plant these areas in Meadow plants, but the labor and herbicide needed on this scale would be far too costly. Your campus, though, seems to have many little pockets of lawn that aren’t needed, and these certainly can be re-done in native grasses and wildflowers. I think, though, that I wouldn’t try to find native grass that can be walked upon by students, but think in terms of taking entire areas out of circulation completely, and leaving the trafficked areas in lawn.

The problem is the amount of traffic in small areas, especially on college campuses. We affectionately refer to these as “goat paths”. No plant can take a constant traveled lane like this, particularly fussy native wildflowers. Focus on a healthy lawn in these areas.

In terms of preparing the soil for your project, there is no way for me to give any specific recommendations from here. A soil test would be a crucial first step before anything happens. I do have some general advice, though. Based on many of your pictures posted on the Facebook group, your campus suffers from the same general problem as ours, that of soil compaction. I see in many of the rainy day pictures standing water in the lawn, and you mention that it is the lawn not able to absorb the rainfall. Truthfully, it isn’t the lawn absorbing rain, but the soil. A hard, compacted topsoil cannot soak in a rainfall, and water does tend to run off. The best cure to relieve compaction is to eliminate the stress (probably foot traffic, lawn mowers, etc.), and to add organic matter, such as compost. Aeration would certainly help as well. Rain gardens can be used where water concentrates.

Here’s a photo of a nice pine stand. No lawn underneath, but who cares? This is probably because of the soil and shade from the pines. There probably are wildflowers that would grow in an area like this, but not many. Dry shade can be tricky.

Photo by Jessica

Here’s the same area (I think, remember I’m 350 miles away), after a hard rain. This screams compaction, possibly from foot traffic heading toward the parking lot? Or was this just a heck of a rain storm?

Photo by Jessica

In terms of other soil amendments, I constantly remind myself that I can’t fight geology-you have to play the cards you are dealt. If your soil conditions are radically different compared to the plants you would like, you probably aren’t looking at the right types of plants. Lists abound of native plants and certain well-behaved non-natives appropriate for all types of soil and landscape conditions .When amending soil one really needs to amend an entire bed, not just planting holes, and these can get costly in large areas. Certainly minor adjustments, such as fixing a nitrogen deficiency aren’t terribly difficult. In general, and listen for many other horticulturists gasping in pain as they disagree, wildflowers don’t need super rich soil to thrive, certainly not like our coddled landscape plants of today.

This is the area mentioned on the Facebook group as the first area to plant. I see evidence of compaction here too.

Photo by Jessica

If I’m reading the maps and your description correctly, I like the area you’ve chosen to trial. Establishing a new bed can be difficult, and it is nice to have it surrounded by buildings/parking lots. I always think of weed infiltration-if the area you want to plant is surrounded by lawn, the seeds from those grasses and lawn weeds can blow in and make the new bed harder to maintain, as the weeds need to be removed frequently in the first couple of years to avoid the competition.(They’re called weeds for a reason!)

Another thought is to work closely with the Grounds department. One of the best parts of our no-mow program was the reduction in labor from constant mowing. We’ll be honest-some of our no-mow areas were picked because we didn’t really want to mow them (!). Some small no-mow areas you may like to plant may take 3 times as long to mow as other areas because of obstructions such as trees and planted beds. You can get a larger bang for your environmental buck by removing these slow to mow zones.

Here’s a picture from the Facebook group of an area you think should not be lawn.

 

photo credit-Jessica

To me, extending the bed from the building would add a tremendous amount of weeding that would have to be done, although it is hard to get the right context where this is on campus based on this picture. If the bed were eliminated and the entire area planted in natives the strip would still need to be mown next to the walk (tick control), leaving an awkward area in between that strip and the building.

This is a good area for no-mow-

photo by Jessica

Extending this existing bed/wild area under the trees would lose quite a bit of lawn, and look in the landscape like a logical extension of the area.

Lose the lawn here too-

Photo again by Jessica!

This area looks unused, with no doors or pathways evidenced. It also looks hard to mow, with a lot of weedwacking. A native stand of plants under the trees would look quite attractive. The trees do seem to be planted in a grid, was this supposed to be (or is) an outdoor recreation area?

Your last question, that of specific plants, I’m afraid I’ll be no use. New Jersey is a world away ecologically compared to the Champlain Valley. A little bit of googling while eating my lunch led me toward some interesting sites-like the Plants of Southern New Jersey, and some interesting work on Native Warm Season Grass Meadows, including an interesting PDF here from the New Jersey NRCS.  I liked Professor Jack Conner’s blog.

I wish you the best of luck. Let us know how it goes.

 

 

Squirrel Business

Categories: Midd Blogosphere

I’m primarily a plant person, because I’m slow on the uptake and not very observant. Someone says “Look at that bird!” and by the time I’m looking even close to the right direction, let alone focusing in on what a bird is, said bird has flown far, far away. Trees, wildflowers, landscapes-easy to see, and prone to stay in one place. Since starting at Middlebury, though, I’ve become enamored of our extensive squirrel population.

Photo Credit-Dan Celik (Thanks!)

Aristotle named the squirrel ‘skiouros’, combining  two Greek words, ‘skia’ for shade, and ‘oura’ for tail, or, in some ancient Greek slang, ‘he who sits in the shadow of his tail’. The French created the word ‘esquirel’, from whence came the English ‘squirrel’.

Our breed of squirrel on campus is the Eastern Gray Squirrel, native to the east coast from Manitoba to Florida and eastern Texas. Squirrel fossils date back to 40 million years ago, and know number over 365 species in seven families, including ground squirrels, tree squirrels, and flying squirrels. Clearly, our Middlebury squirrels are tree squirrels. This time of year their nests, or dreys, are seen high in some of our trees, or in the several hollow trees we have scattered about.

We seem to have some squirrel ‘families’, or at least some serious inbreeding going on, although it does not seem to be as notable this year as in past years. While all white or black squirrels can often be seen in urban populations with little to no predation, up by Mead Chapel for the last several years we had a group of gray squirrel with thin, wiry red tails, more like a red squirrel. The difference in the squirrels between Mead Chapel and the library quad was quite striking. Now the Mead squirrels have fluffy tails, but they are still red.

Squirrels are ‘scatter hoarders’, making many small caches of food in various locations. They are known for their spacial memory, remembering where up to 1000 of these sites are. Food types are generally tree seeds, including many nuts, although they’ve been known to feast on fungi and tree bark as well. When food is scarce they will even turn carnivorous, eating insects, frogs, small birds, even other squirrels (!).

They are most well-known for feasting on nuts, however. In fact, their love of seeds started this post. While preparing to remove the lightning struck spruce, we noticed a large cache of spruce cones underneath the tree. Given a sudden abundance of a food source, a squirrel will make a temporary pile to await better burial and hiding later. Spruces were prosperous this year in cones, and if you’re a squirrel you can’t let a good thing go to waste. The seed of the spruce sits at the base of a seed scale, and each cone can have many scales. Squirrels seem to process the cones, flaking away the bracts to reach the seed, and then later burying the seeds for retrieval later.

 

If I were a squirrel, though, I’d be waiting for acorns. A good source of protein, their size is probably a meal unto itself. While humans don’t like the bitter tannins found in many acorns, the squirrel doesn’t seem to mind.

 

I remember my first fall here at Middlebury, and thinking our Red oaks had a terrible disease. The ends of the branches, the new growth, would lie scattered about the base of the tree. Dan Celik, custodial supervisor extraordinaire, has noticed the same thing, and took pictures for the blog. Squirrels, even though they have a brain the size of a small walnut, aren’t too dumb. They go to the end of an oak branch, and gnaw with their teeth until the end falls to the ground, where they can easily and quickly harvest the bundle of acorns attached.

Photo Credit-Dan Celik (Thanks!)