Tags » Weather

 
 
 

Watering

July 24, 2012 by
Categories: Landscape

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.

Tags: , , , , , ,
No comments »

Season Creep

March 21, 2012 by
Categories: Blooms, Landscape

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.

Tags: , , , ,
No comments »

A Better Weather Forecast

February 23, 2012 by
Categories: Weather

Thanks to an Environmental Grant several years ago, the Landscape department has been running a personal weather station down at the track off of Porter Field Road, with a second more recent station up at Breadloaf campus. We depend on these stations for primarily for snow removal and IPM strategies. The data are also streamed to the Weather Underground, a weather web site that accumulates and posts data for over 10,000 stations across the US.

Any compulsive weather addicts know how tricky it is to forecast weather for a region-most people say the forecasters are “wrong”. A better interpretation would probably be to say they aren’t accurate, and Vermont is a great example of why. The National Weather Service has various offices, and ours is in Burlington at the airport. They cover a large area, from Lake Placid to Montpelier, and from the Canadian Border to Killington. The only way to accurately forecast an area this large is to break it into regions. For example, our region is number 9, Western Addison, including the cities of Vergennes and Middlebury. And here lies the problem with forecasting, particularly in the winter. Middlebury campus is under the same forecast as Lake Champlain, and Vergennes shares the forecast with Brandon. It’s a huge geographical area, and one forecast for such a space is bound to lose accuracy across the region. Addison may get an 1″ of snow, low in the valley, while East Middlebury may be getting hammered with 6 times that, under the same forecast.

The Weather Underground has been taking the National Weather Service forecast, and re-packaging it on their website, along with access to some great radar maps, blogs, photos, etc. Recently, however, they’ve starting forecasting themselves, called Best Forecast, and what makes this different is the data, not only from all of the NWS weather stations, but all of the personal weather stations such as ours. Slate just wrote a great article explaining this. Suffice it to say that Best Forecast is now taking into account microclimates, so when pulling up a Middlebury forecast on the WU, we are getting a Middlebury campus forecast.

How accurate? We’ll find out tonight and tomorrow. The NWS is forecasting a dusting to 2″ of snow tonight, with an additional 3-5″ possible tomorrow before it changes to rain. Temperatures mid 20′s tonight, mid 30′s tomorrow. Best Forecast? Lows of 28 tonight, 50% chance of snow or rain, high of 45 tomorrow, snow than rain in the afternoon, snow accumulations of 1″ possible. I’m not placing bets on who is correct here, but the Best Forecast feels right to me. I’ll post an update when all is said and done.

UPDATE 4PM: The NWS issues forecasts at fairly regular times, 3 PM or so being fairly regular. Their update for the western addison zone has changed slightly, 2-4″ during the day tomorrow, changing to rain in the afternoon, back to snow Friday night with an additional 1-3″. Mid 30′s tomorrow, mid 20′s tomorrow night. Best Forecast has changed little-snow and rain tomorrow, accumulation 1″, chance of ice pellets, snow and rain friday night, only 60% chance, no accumulation mentioned.

UPDATE 12 NOON FRIDAY: The NWS has changed their forecast, as the storm seems to have slowed down from the west. No snow last night, and only light snow now at noon, not accumulating. So do we call this a win for Best Forecast? Both forecasts now are in line with each other for snowfall tonight, 4-6″, but Best Forecast is calling for temps today around 45, with the NWS saying mid 30′s, which it is now. I’d be surprised if temps rise today.

Tags: , , , ,
No comments »

Lightning 1, Spruce 0

December 7, 2011 by
Categories: Landscape, Trees, Weather

Anyone around this summer, or past readers of this blog, will remember a large thunderstorm that ripped through Middlebury two days after Independence Day.  Several trees were struck by lightning, which I wrote about after the storm.

The largest tree struck was the Norway spruce in the Main Quad, one of the ones remaining after we removed part of the line. I wrote this summer how the tree was struck at the top, and exhibited a spiral shaped scar all the way down the trunk, exiting at the root flare. We didn’t know if the tree was going to make it or not, but had hopes.

It’s not the voltage that kills trees, but the water. Over 100 million volts strikes the tree, but it is the water heating quickly turning to explosive steam that causes failures. (Another blog post, on a lightning stuck Ginkgo, has much more detail) Damage in trees can be tricky, often with the worst of the damage unseen.

There was damage seen immediately. Long strips of bark went flying across the quad, and a scar opened up, spiral shaped, following the grain of the wood down the trunk. The high sap content of spruce makes it susceptible to such long scars.

I’d been worried about this tree all summer, and was watching it closely. All the limbs near the scar started to die, and the color of the remaining ones seemed a little off, but still green.

During a closer hazard evaluation this summer I discovered two things, one bad, the other worse. The first was the size of the scar, and while this shouldn’t have surprised me, it did.

The scar that formed in the summer seemed minimal. While very long, it only seemed an inch or so wide.

Scar in summer

The bark hid quite a bit of damage, and another small crack that wasn’t even open this summer showed another major wound. Peeling away at the wound showed extensive damage, much larger than we’d first thought. Overall, it seems about 1/3 of the sapwood (the live wood beneath the bark that conducts water and nutrients) around the trunk has died, severely compromising the tree.

I’ve seen trees limp along with scars like this for many years, most often in a forest setting. Trees in communities are connected in several ways, relying on each other for support and nutrients. They also tend to be the best trees for the site, adapted to soil and weather conditions. Trees in an urban or landscape setting are under more stress, either from a singular status in the landscape, more exposed to wind by themselves, or stress from poor soil conditions its genetics just can’t handle gracefully.

This fall was a good one for fungus, with cool moist conditions. The base of this spruce showed a colony of fungi following along one of the major roots of the tree. Later that same month the same fungus appeared following a different root. This indicates a root rot, a type of fungus eating away at the roots of the tree.

I’ve spoken with an arborist friend of mine who suggests immediate removal. He’s seen similar cases, where trees exhibiting root rot like this suffer from wind throw, heaving over in a storm. The clay soils of our quad make this species very susceptible to this, spruce not being a deep rooted tree to begin with, in clay soils even more so.

While I like this tree quite a bit, the chance this tree could suffer a catastophic failure in such a busy location on campus is too much of a chance to take. The remaining tree, the large Norway spruce with the interesting trunk, will remain.

Tags: , ,
3 Comments »

Irene Still Hanging Around

September 1, 2011 by
Categories: Weather

Like a guest that just won’t leave, the effects of Irene the Hurricane still seem to be around Middlebury. Primarily what we’re watching now is the Otter Creek.

South Street-flooding in the fields

It takes a while. All the headwaters that feed into the creek have been slowly dropping, like my own muddy Lemon Fair River, and so the Otter Creek is rising. How fast? The football team, at Middlebury for pre-season practice, skipped the weight lifting today and went to fill and stack sandbags at Jackson’s on the River (the old Tully and Marie’s to you alumni) ( The old Woodie’s to you older alumni). (Great little article here).

Another stream feeding the deluge is the North Branch River, the one that falls along Route 125, heading up to Breadloaf and the Snow Bowl. Last I heard, the road is still closed (picture here), although Breadloaf is still accessible by back roads.

Otter Creek Levels-via National Weather Service

As I write, the Otter Creek in Middlebury is at 6.9′, within the top 20 crests of all time, and is thought to reach peak tonight around midnight. Not wanting to wait that long, I took some pictures downtown to try and capture the feel of a simply amazing amount of water, brown and muddy, crashing through town. One of our seasonal landscapers was a dairy farmer in Orwell for 30+ years, and in his experience he’s never seen water so muddy. Another guy in our shop is at home, an island experience, surrounded by water on all sides unable to come to work.

On Battell Bridge Looking East

Jackson's on the River

The Falls

Looking under Battell Bridge

The Bottom of the Sluice

 

 

Tags: , ,
No comments »

Irene visits Middlebury

August 29, 2011 by
Categories: Weather

Given all the flooding and destruction in the state, I feel very fortunate here at Middlebury, and at my house overlooking the Lemon Fair (flooded, but looks like a normal spring). While we certainly had some damage on campus, it feels relativly minor compared to friends in East Middlebury in need of a new backyard.

Irene brought 3.21″ of rain to the main campus weather station, to bring a wet August total to about 7 3/4″ of rain. The peak wind registered was 37 mph, at about 6:30 yesterday. Breadloaf campus saw 5.13″ of rain, bringing their August rain to 11.27″. They saw a peak wind gust of 39 mph, later in the evening than down in the valley.

No major problems occured on campus. Facilities was busy with their usual leaks here and there, but it didn’t seem any more significant than another big rain. We’d spent a chunk of Friday mobilizing for the storm; gassing and sharpening chain saws, getting wet vacs ready, checking pumps.

Monday morning dawned clear and fresh, and revealed a mid September amount of fallen leaves, along with a plethora of sticks. Some large branches broke in the wind, as well as having a couple of trees topple over. Overall, however, I was pleased with the relative lack of tree damage. This late in the year weak trees are already shedding their leaves, or have thinner than usual crowns, so the more storm prone trees have less “sail” to catch the wind. A large limb heavy with black walnuts fell behind Turner house, but other fruit bearing trees did fine.

The immense rain in a short amount of time causes the most damage for trees. The soil below the tree turns to soup, roots lose their holding capability, and trees can topple in the wind. A good example is a Basswood lost right below Gifford, at the base of the ledge. All the water percolates a little ways down the soil profile, until it hits the ledge, then drains downhill right towards this tree. Combine that with the lack of roots on the ledge side of the tree, and the reason this tree fell is pretty clear.

Basswood below Gifford Hall and Mead Chapel

Another tree with a compromised root system was a Poplar growing out of a stone wall behind the Hadley House Barn. One of our crew members commented how the roots went right through the wall, and this was a good reason to remove sucker trees before they get too large.

Poplar Tree at Hadley House

The rotting root system in the wall

Overall, we did fine. Here’s another couple of pictures of some damage, we’ll have it cleaned up in another day or so.

Blue Spruce by Fletcher House

This one was tricky. A Black Maple on the east side of Old Chapel lost a large limb, breaking another couple, but the limb was held up in the tree by an old cabling system, so extracting the limb from the tree involved some minor rigging and rope work.

Last picture-weeping willows always look so dramatic when broken. This one, located behind the esteemed Francois’ house, lost two major limbs, but had the good grace to avoid the power line right below. He and his dog watched it fall. No, the dog was not in the crate at the time…

Tags: , , ,
1 Comment »

A Wednesday Thunderstorm

July 10, 2011 by
Categories: Trees, Weather

Last wednesday we had a rip-banger. Thunderstorms developed in the hot summer air over Northern New York, and built as they tracked across the lake. The line continued to build once across the lake, and erupted on top of Middlebury.

I was sitting at home, (I was at work early), watching lightening strike all around us, many up on the ridge of Snake Mountain, some in the fields below. The wind was howling, and sheets of rain poured down. The Middlebury weather station recorded a 20 degree temperature drop in less than a half of an hour, and more than a half an inch of rain in the same amount of time. Peak wind gust came in at 40 mph.

The college weathered the storm ok, but 3 trees took it quite hard. A Green Ash behind Emma Willard (Admissions) took a lightning strike-that was interesting, as it was the shortest tree around, but it was all by itself in the center of the back yard.

Another tree we lost, not surprising, but still sad, was a large Weeping Willow on the northwest side of Battell Beach (the upper Quidditch Pitch). We almost always see Adirondack chairs underneath this tree. The center two stems of this tree had a fast moving fungus that caused a rot in the sapwood of the two center trunks. The sapwood is what carries water upwards to the branches, as well as nutrients throughout the tree, so having this vital structure rot away was a irrecoverable death in waiting. High winds torqued one of the trunks, and broke it away to lean against one of the remaining ones. We removed the tree the next day, before it broke further on someone sitting in a chair.

The final tree may or may not be a casualty, time will tell. One of the large Norway spruces we left in the Main Quad Tree Removal, the most southern one, was hit by lightning. Friends at work in the service building told me it was the most impressive lightning strike they’d heard in a long time. The tree shows a classic spiral scar from the top of the tree all the way down to the bottom root flare. Bark like shrapnel was scattered all over the quad in long 3′ strips, and filled the back of one of our gators. The prognosis of the tree is unknown. The roots seem to be intact-while there is bark peeling on the root flare, it does not seem too bad. Certainly I’ve seen trees recover from worse. We’ll know in a couple of weeks-if the tree is going to die quickly we’ll know soon.

Tags: , , , , ,
No comments »

Lake Flooding

May 8, 2011 by
Categories: Weather

We’re a little removed from Lake Champlain up in Middlebury, but probably not as far as you think. My own house sits above the Lemon Fair River, draining into the Otter Creek north of Middlebury, which empties into Lake Champlain just north of Vergennes. The lake itself also drains to the north, out the St. Laurence Seaway, which seems counter-intuitive. Everything is supposed to flow south and down, right? Wikipedia says the residence time (the amount of time the lake turns itself over) is 3.3 years. That’s some serious water flow.

The lake peaked a day or so ago at 103.25 feet, that’s the elevation above sea level. It is considered above flood stage at anything over 100′, and seems to spend most of the summer at about 95.5′ above sea level. That means the lake is 7 3/4 feet (!) higher than normal. The previous record, which I remember from a job being a caretaker on a lakefront property, was 101.88′. So all that snow we were cursing this winter? It’s still around.

The Lake Champlain Basin Program has a picture gallery up of flooding and sediment flow that’s worth a look, and below is an animated GIF from the National Weather Service of Hi-Res satellite pictures of the snow melting off the Green Mountains.

Tags:
No comments »

Some snow

March 10, 2011 by
Categories: Weather

The most remarkable thing about this last snow storm on Monday is probably the fact I almost didn’t write about it. After this punishing winter of snow removal, yet another storm didn’t seem worthy of taking the time to whine. But, after setting some records, I thought I’d write about it, if only so students can brag to their parents.

We don’t know how much snow we got here on campus, as the wind was drifting the snow so radically that some places were devoid of snow, while others were 6′ deep in drifts. I asked the guys in the landscape department how much snow we got, and the answers are unprintable. I measured 20″ in my driveway, but that was pretty windblown too. According to the National Weather Service, Cornwall got 22″, Bridport 24″, so we’re thinking somewhere in that neighborhood sounds about right.

Snow Totals Map-click for larger version

This is one for the record books, both the storm and this winter. The Burlington Weather Service office recorded 25.8″ of snow, beating our Valentine’s Day storm of 2007 by a tenth of an inch. (Incidentally, the record storm was last year, January 2-3, where they got 33.1″. I’ve erased that from my memory) This is the largest March storm, however.

In terms of our yearly records, we’re at 124.3″, third highest total. Number two comes in at 132″, in 1886-87, and the record holds at 145.4″, in 1970-71. I can see us beating 1886, but if we break the ’70 record there is going to be some sore shovelers at Middlebury.

Speaking of sore, yes, there are still some sidewalks not cleared yet. We’re trying! The problem with massive snows like this is that our regular plows just can’t handle it. You can only push a huge pile of snow for so long before the wheels start spinning or you have nowhere to put it. For these types of events we put large snowblowers on a couple of our tractors, but that’s slow going too. And because classes were still being held, the extra sidewalk traffic impeded progress all the more. Uncleared sidewalks means snow shovelers are walking through snow from building to building, dragging a snowblower through drifts.

And on top of all of that, a lot of us couldn’t even get to work. For the most part, the only workers that made it in lived in Middlebury, except for snow miraculous sidewalk tractor operators, who I’m thinking were airlifted in. My own road was roughly plowed by a Monument Farms tractor half the size of my house-the cows have to be fed-but the town plow didn’t make it until the end of the storm Monday evening.

Tired of the snow? If it makes you feel any better, the stake at the summit at the top of Mount Mansfield says they’ve got 90″. That’ll be there a while.

Tags: , ,
No comments »

This Winter, explained.

February 25, 2011 by
Categories: Weather

Some of our winter weather is controlled by a weather oscilliation know as the North Atlantic Oscilliation, or NAO. This is defined by the difference in atmospheric pressure between an area above Iceland and above the Azores. Ordinarily, low pressure in the winter sits over Iceland, and high pressure over the Azores, and this creates the Polar Vortex, which is simply wind and weather spinning counter-clockwise around the north pole. Picture the two pressure systems as gate keepers, keeping the cold wind spinning around the pole. This strong low pressure over Iceland also draws air from the south west across Eastern North America, giving us somewhat more mild air. Weather scientists call this a teleconnection, or linking of pressure systems across broad geography.

This winter, extraordinary high pressure sat over Greenland, matched by high pressure over Alaska. This caused a breakdown in the polar vortex, causing cold arctic air to dump southward, on top of us. This cold air spilling south is replaced by warmer continental air. A similar event happened last winter as well. Scientists are blaming our colder than normal temperatures and our increased precipitation on this unusual pattern.  Much research is taking place now on this event, known as a Warm Arctic/ Cold Continent.

Average Pressure Pattern

High Pressure, February 2010

The reason for this is a disturbing lack of arctic ice. In January, there was a record setting amount of missing ice in the Arctic, about twice the size of Texas. In the summer, more heat is absorbed by the ocean, which releases in the fall, warming the air above and causing the high pressure. Ocean temperatures are well documented to influence weather patterns, such as the El Nino events, or even hurricane patterns in the Atlantic ocean. And most weather researchers are laying the blame of the lack of arctic ice right at the feet of global warming.

This weather pattern has been breaking down the last couple of weeks, as low pressure is forming in the arctic, creating more sea ice, keeping the cold air locked in the polar vortex. It may be that the groundhog was correct, and our exceptionally snowy and cold winter may be coming to an end.

Tags: ,
No comments »