Thursday, October 11, 2012

Maynard Walking Tours

In 2012 the Maynard Historical Commission, with the aid of a grant from the Maynard Cultural Council, compiled five self-guided historic walking tours of Maynard. Each two-page guide can be picked up at Town Hall or the Maynard Public Library or downloaded as a PDF from townofmaynard-ma.gov/resources/walkmaynard. There is no app.

Walking Tour #1 (Main Street and the Mill): For newcomers to town this stroll along Main, Summer and Nason Streets is a great way to become familiar with downtown storefronts. Estimated distance is two miles. Starts and ends at Memorial Park, on Summer Street, with free parking adjacent in the town's parking structure. Restrooms at various restaurants en route. What is interesting is leaning how many sites have been repurposed over the years. At the entrance to #11, look down for evidence that this town once had a Woolworth's.

Walking Tour #2 (Assabet Village): Estimated distance is two miles. Mostly older houses (1830-90). Starts and ends near the Library, so free parking. This stroll west on Summer Street passes by remnants of farms (barns, one silo), Victorian era mansions and several repurposed school and church buildings.

Orthodox Church dedication plaque

The return (eastward) trek on Summer and then Concord Streets was the line of march for the Stow Minutemen heading toward Concord the morning of April 19, 1775. Do not miss the blue-domed Holy Annunciation Orthodox Church at 15 Prospect Street.

Walking Tour #3 (New Village and Maynard's Hill): This tour starts and ends off Main Street, but most of it meanders through what was mill worker houses constructed circa 1900-1920, on the streets named after Presidents. Estimated distance is two miles.

Lorenzo Maynard's mansion, built 1873
The first part of the walk ascends Walnut Street and then Dartmouth Street to the site of Lorenzo Maynard's mansion - still standing but now divided into apartments. A bit farther along Dartmouth Street (not on the tour) is the site of what was Amory Maynard's even larger mansion - since burned to the ground and replaced by a brick apartment building. From this hill father and son could look down on all they commanded. 

Walking Tour #4 (Great Road): This is actually two walks, each of an estimated distance of two miles. Together, the tours encompass Route 117 from Erikson's Ice Cream, near the Stow border, to the Glenwood and St. Bridget's Cemeteries, near Sudbury.

The Smith family were early settlers along Great Road, which served as a stagecoach route to points west. Sons and grandsons owned houses, many still standing. The dam across the Assabet River is the Benjamin Smith Dam because it was his property, sold to Amory Maynard and William Knight to provide water power for the initial mill.

Town's winter storage crypt
Glenwood Cemetery has a receiving crypt, albeit no longer in use. Frozen ground made digging graves near-impossible in the years before power equipment. Caskets were parked, so to speak, in this structure until the spring thaw. Look for a small structure facing Route 27 with "1888" over the door.

Walking Tour #5 (Assabet River National Wildlife Refuge): ARNWR can be accessed from five parking areas; one of those, in from the main entrance off Hudson Road, is adjacent to the Visitors' Center, which has restroom facilities. Bicycling is allowed on approximately half of the fifteen miles of paths. No dogs allowed, nor any motorized vehicles. The Refuge is open from sunrise to sunset, but the Center's hours are limited to THUR-SUN, 10-4.

All this was active or abandoned farmland until seized by the U.S. Army in 1942 to be made into an ammunition and explosives storage area. After the war this site, referred to as the Fort Devens-Sudbury Training Annex, served as a troop training ground, ordinance testing and laboratory disposal area. Subsequently, it was designated an Environmental Protection Agency “Superfund” clean-up site then turned over to the U.S. Fish & Wildlife Service in 2000 for a wildlife refuge.

Click on photos to enlarge.      

Friday, September 7, 2012

Invasive Plants: Bittersweet, Knotweed, Garlic Mustard...

One plant species a year is written about as "Invasive Species of the Year."  Tree-Of-Heaven for 2013; Garlic Mustard for 2012; Japanese Knotweed for 2011; Oriental Bittersweet for 2010. All four columns are consolidated below. Click on any photo to enlarge. 

TREE-OF-HEAVEN 

Ailanthus altissima is the Latinate name for tree-of-heaven, a tree native to China, and thus invasive in the United States. The common name refers to its extraordinary growth rate. Ditto the Latinate name: Ailanthus derives from an Asian word for sky-reaching-tree while altissima has Latin roots in altus, for high or highest.

As with many invasive plant species the initial introductions were deliberate. By the 1840s these trees were being sold commercially for garden plantings. One route was China to England, thence to the eastern United States. Tree-of-heaven was a popular city planting because it thrived in poor soil and is resistant to drought and pollution. In California, immigrant Chinese workers at mines and railroads brought tree-of-heaven with them for its traditional medicinal purposes - the bark used to make an astringent tea.

Trees are either male or female. Both have flowers, but only the female trees create seed clusters. A mature tree can produce more than half a million seeds in a single season. These disperse by wind, and are rarely eaten by birds, mammals or insects. Deer will not eat the leaves nor nibble on the bark of saplings. Trees - both male and female - also are producers of new shoots from a far-reaching root system, so what starts as one tree can easily become a thicket.

This species does not play well with others. As with garlic mustard, this plant produces chemicals which inhibit the growth of other plants, a trait that is referred to as being allelopathic. Combine that with prolific seed production, a growth rate much faster than any native tree, plus resistance to pollution and drought, and this tree is a nuisance in urban and semi-urban environments unless vigorous combated.
  
Young trees have smooth bark
Tree-of-heaven smells bad. One disparaging nickname is 'stink tree.' Anyone who has tried to pull up seedlings or cut sprouts knows this tree has an offensive odor - sometimes described as having overtones of rancid or burnt peanut butter.

Tree-of-heaven is difficult to kill. Cutting results in new growth from the stumps that can exceed ten feet in the first year. Cutting will also stimulate a massive production of shoots from the surviving roots as far away as ninety feet from the original trunk. Any site where a mature tree was cut down will require follow-up cutting of new shoots several times a year for at least five years.

Systemic herbicides that kill roots (for example, triclopyr and glyphosate) currently provide the best chemical control for tree-of-heaven. These can be sprayed on shoots, or holes can be drilled in the stumps of freshly cut trees and the high concentration herbicide products applied directly. Both application methods can cause collateral damage to nearby plants. 

GARLIC MUSTARD

No, "Garlic Mustard" it is not some vile genetic modification experiment escaped from the laboratories of agri-business. Rather, garlic mustard (Alliaria petiolata) is a European plant naturalized to New England and other parts of the United States more than 100 years ago. It is in the mustard family, but the leaves of this sub-species have a mild garlicky smell when torn or crushed.

Garlic mustard is one of the few woodland plants flowering in early May. The plant has a two-year life cycle: close to the ground the first year, than taller and with flower stalks topped with small white flowers the second year. The flower stalks are one to two feet tall, capped in bouquets of four-petaled white flowers in the shape of a cross. The plant prefers full or partial shade to full sun.

Garlic mustard: second year plants 1 to 3 feet tall
The problem with garlic mustard is that it is displacing native woodland species. Invasives, by their nature, do not play well with others. Once transported these species find themselves in a new land not populated by their natural enemies. This plant in particular not only physically displaces native species but is suspected of waging chemical warfare. According to a Michigan State University website "Several compounds isolated from garlic mustard were shown to depress growth of both grasses and herbs in laboratory experiments. Researchers concluded that release of these compounds from garlic mustard root systems might account for its dominance in forest ecosystems. Others have suggested that such compounds might also disrupt mutually beneficial relationships between plant roots and certain fungi in the soil, known as mycorrhizal associations. These fungi are used by most North American forest ground-layer plants and are critical for nutrient and water uptake in many trees."

While immigrants to America get most of our attention, American species can be invasive after crossing in the other direction. Poison ivy now exists in the wild in the United Kingdom and Australia because it was planted as a garden ornamental. Bullfrogs are a spreading menace to native amphibian species worldwide. Grey squirrels are displacing native red squirrels in ItalyIreland and England; in the last an "Eat the enemy" campaign has received lots of media attention.

Cross-shaped flowers appear in May
Garlic mustard is relatively easy to pull up, roots included. Hand pulling, however, is very labor intensive, and can result in soil disturbance, damaging desirable species and putting soil at risk for erosion. An alternative is to cut the plant as close to the soil surface as possible, either with pruning shears or a weed wacker. Pulled plants should not be composted, especially those in seed, as the seeds are resistant to temperatures reached in compost piles and remain viable for years.




JAPANESE KNOTWEED

 Japanese knotweed (Polygonum cuspidatum), also known as Japanese bamboo, is a winter-hardy transplant from Asia. It is water- and sun-loving, and so can be found alongside marshy areas and roadside drainage ditches. Knotweed’s hollow, smooth stems and rapid growth gives it a superficial appearance akin to bamboo, hence the common name, but the species are not related.

New stems grow from the roots each year, quickly reaching heights eight feet or higher. The main-trunk stems are more than one inch in diameter. The plants branch into narrower stems that are horizontal or drooping towards the ground, with large leaves to either side of the stems. Fall finds these branches topped with wispy white flowers. At first frost, the leaves die, but dead stems remain standing, orange-brown in color, all winter and into next spring. An example of a colony of these plants can be seen at the northern edge of Tobin Park, which is behind the Blue Coyote restaurant. 
Japanese knotweed clusters spread from roots



As with many invasive species, Japanese knotweed was first introduced to the United States towards the tail end of the nineteenth century as an ornamental plant. Its dense growth crowds out native species while providing little in the way of sustenance or shelter for native animals.

Knotweed is extremely difficult to eradicate. Cutting stimulates new growth. The root system is very broad and very deep. After any attempt to remove it by digging it out, even small remnant sections of roots can start new plants. According to at least one report, even cut stem pieces can form roots, so cut material should not be added to piles of plant material intended for composting and reuse in gardens. 

Success in removing knotweed usually involves a multi-pronged approach involving cutting, digging, herbicides and covering the afflicted areas with tarps for the entire growing season. Experimental testing is underway with biological management using either insects or leaf fungus disease apparently specific for knotweed.

A little-known fact – knotweed roots are used as the source material for the popular dietary supplement ingredient resveratrol. Thus, while resveratrol is widely known to be found in red wines and (mistakenly) attributed all the health benefits of red wine, what is sold in most dietary supplements is not grape-derived. Resveratrol, whether grape, knotweed, or synthetic, does not yet have any proven health benefits in humans. Researchers are still in the preliminary stages of figuring out safety. There is evidence resveratrol prolongs lifespan – in mice.

ORIENTAL BITTERSWEET

Volunteer cutting large bittersweet vines on Summer Hill
Oriental bittersweet is a slow-motion disaster for the trees of New England. This ornamental plant “gone wild” was introduced to the  U.S. in the mid 1800’s and widely naturalized by the early 1900’s. When fully grown it can overtop sixty foot tall trees, breaking branches with its weight, and finally, killing the trees. Examples of its extent and damage can be seen in Maynard along Rockland Avenue and from the footpaths on Summer Hill, and in Stow along Pompisitticutt Street.

Infestations of bittersweet are easiest to see in the winter, when the red berries are a colorful haze across bare treetops. In spring the over-wintered berries are consumed by birds, contributing to the spread.

Bittersweet likes full sunlight. It tends to grow fastest on trees bordering roads and open spaces. Growth rates are 5-10 feet/year. Stems up to an inch or so in diameter are smooth, with increasing roughness as mature stems thicken to 3 to 4 inches in diameter. These vines are easy to differentiate from other vines. Poison ivy clings to the bark of the trees with thousands of fuzzy rootlets and rarely exceeds 15-20 feet in height. Wild grape vines have a brown, flaking bark.

Wreath, showing bittersweet berries
Combating bittersweet is both a private and public virtue. Property owners can begin by policing their own property. Vines should be cut as close to the ground as possible and also as high up as it is easy to reach. The gap makes it harder for the new shoots to reach the old vine ends and get back into the trees. In time, what is left up in the tree will rot and fall. For those who would complain that the vines will just grow back, so does grass – but you commit to cutting that twice a month. Hardware stores should have products that can be applied with a brush across the cut stems to block regrowth. Small vines can be pulled up roots and all. The roots are identified by a reddish-orange color. Just take care that you are not pulling up poison ivy, which can also be a ground based, woody-stemmed plant.

Volunteer-minded individuals could approach the Conservation Commissions in Maynard and Stow for guidance on addressing our bittersweet problems. Much as there are organizations committed to cleaning the Assabet River and picking up trash, towns need a coordinated effort to save the public woods. The Friends of the Assabet River National Wildlife Refuge periodically schedule work events to combat invasive plant species in the Refuge. Details are on the website (www.farnwr.org).

Invasive species are noteworthy based on how much they disrupt the ecological balance of their new land. Various world lists of the one hundred worst invasive species are not limited to plants. Insects populate the lists, as do mollusks, crabs, birds, reptiles (Burmese pythons in Florida!), and even a smattering of mammals such as pigs, goats, cats and rats. Our international travels and trade continue to promote accidental or intentional introduction of species. An outbreak of Asian longhorned beetles is being combated near Worcester. In 2009 an outbreak of zebra mussels was found in Laurel Lake in the Berkshires, and a “late blight’ fungal infection damaged much of the tomato plants bought for home vegetable gardens.

Thursday, September 6, 2012

Tobin Riverfront Park

Update (April 2017): Construction on the Assabet River Rail Trail, which runs through Tobin Park, has resulted in much of the park being enclosed in a construction fence, the wooden footbridge removed in 2016 and a replacement bridge installed but not open as of April 2017. Trail consruction should be completed by fall 2017, and the park to get new landscaping and plants either late 2017 or early 2018. See entries in 2017 for construction updates. 

Dedication marker
John J. Tobin Riverfront Park encompasses greenspace on either side of the footbridge over the Assabet River, located at the east end of the parking lot behind the Post Office. Maynard's smallest park, so small it is not even listed on the town's website map of open spaces and trails, turns 23 years old this month (Sept 2012).

According to an article in the October 5, 1989 issue of the Beacon, in the microfilm collection of the Maynard Public Library, the park was dedicated in late September 1989. Close to 60 Tobin family members, friends and local dignitaries attended. The park project cost $142,036 and was partially funded by the Executive Office of Communities and Development Small Cities Program, and the Department of Environmental Management. 

Prior to the park's construction the area had been a brownfield eyesore. Long after the trains had stopped running the deteriorating trestle bridge and bordering land were overgrown, neglected, and had become a hang-out for town drunks, derelicts and homeless. Men slept in corrugated cardboard shanties.

Wooden footbridge over Assabet River 1989-2016
Bridge was 6' wide, replacement 16' wide
Tobin had been a long-time resident of Maynard. He was a Board of Public Works member for over 30 years, and also active at times on the town's Finance Committee, School Building Committee and the Board of Appeals. Tobin was instrumental in starting the Boys & Girls Club of Assabet Valley. He was so active in town that many people referred to him as "Mr. Maynard." His death in 1986 was a catalyst for the town's government to choose some means of remembering his contributions.

In addition to Tobin's involvement in town government, he and his family ran the very successful Tobin Vending Service, which among other clients, had a contract for vending machines for Digital Equipment Corporation.This pocket-sized park sports a wood-decked footbridge across the Assabet River, two picnic tables - perfect for a weekday outdoor lunch - and ten benches.

Some of the original landscape plantings still grace the park, but around the edges wildness had set in over the years. By 2005 the upstart growth was so thick that it was barely possible to glimpse the river. Maple saplings, poison ivy, Oriental bittersweet vines and Japanese knotweed were rampant. Finally, volunteers stepped in to clear saplings and undergrowth, and the town's Department of Public Works effected some repairs.

As a result, this is one of the few places in town it is possible to walk right down to the riverbank. Barefoot wading is not recommended, however, as while literally hundreds of pounds of broken glass, pottery shards and rusting metal have been removed, much remains.

The river brings many moods to the park. The flood of March 2010 brought water to within a foot of the underside of the footbridge, and a flow rate of 2,500 cubic feet per second. This summer's low trickled by at 20 cfs - not enough to float a boat. Winter adds ice stalactites to the river's borders whenever the water level is slowly falling while temperatures stay below freezing.

Adult Canada goose

Wildlife sightings include many birds, a few species of fish, frogs and crayfish. During summer's low water a lone Great Blue Heron often stalks the river in search of breakfast. Rarer sightings have included snapping turtles, raccoons, skunks and the occasional garter snake. Flocks of geese step out of the river to nibble on the grass. It's a nature oasis in the center of town.


In the future the park will undergo another transformation, as the plans for the Assabet River Rail Trail call for a new bridge and a wider path. The soonest this might happen is 2016. For now, let's all give thanks to the memory of John J. Tobin, and the tiny gem of a downtown park named in his honor.

Friday, February 17, 2012

Age and Peak Athletic Performance

Sarcopenia - age-related muscle loss - becomes more common
and more severe after age 60, but even for 80 year olds a supervised
program of resistance exercise can add strength and improve quality of life

Peak athletic performance is reached at age 30, with remarkably little decline for the next ten years. After 40 there is a slow, steady decline to age 60, accelerating thereafter. The mid-life decline is a consequence of less oxygen being delivered to muscles; the late-life decline to a complex web of less oxygen delivery plus loss of muscle mass, compounded by disuse, obesity and osteoarthritis. But there is hope.

At the direct physiological level, theories span loss of function of nerves that control muscle movement, less oxygen uptake in the lungs, decreased oxygen delivery by blood, lessened availability of fuel, and poorer fuel use efficiency. While lung function can decline with age, especially in smokers or people with occupational exposure to airborne chemicals, the main cause is ever-decreasing oxygen delivery. With age there is a decline in maximum heart rate (roughly estimated as 220 minus age), less blood volume per heartbeat and progressive loss of capillaries delivering oxygenated blood to muscle cells. 

Fuel availability and usage are not part of the problem - muscle cells have adequate access to fuel and do not require more calories to contract. This aspect, known as "exercise economy," is assessed by looking at the metabolic calorie cost of sustained submaximal exercise.

Other changes factor into sarcopenia. Beyond 60 years, sensitivity is lessened to the signals which in younger people will trigger muscle enlargement, for example, vigorous exercise or consumption of a high protein diet.

Indirect contributors to the age decline include disuse, obesity and osteoarthritis. After college age, few people have physical labor jobs or sufficient leisure time for the 20 to 30 hours of training per week needed to maintain a level of physical activity necessary for peak performance. Recovery from sports injuries take longer. Body fat, especially torso fat, is pre-inflammatory, contributing to muscle cell insulin resistance; without this anabolic signal being received, muscles shrink. Osteoarthritis has a chicken-or-egg-first relationship with fitness, as exercise slows the progression of osteoarthritis, but this disease is a major reason people stop being physically active.

Certain sports appear to contradict the "peak at 30" hypothesis, but on closer examination, may not. For many years women's swimming and tennis were dominated by teenagers. These individual-effort sports channeled young girls into early commitment and intense training. The typical result was an early-age peak followed by mental burn-out and/or career-ending physical injury. With wider access to competitive sports via Title IX, a broader pool of women athletes across a wider range of sports finds peak ability reached in close to 30 years, just like men. In the New York City marathon, women in their mid-40s are competitively close to women ten and twenty years younger.

The net result of the direct and indirect consequences of aging? For healthy, well-trained endurance athletes there is a 20 to 25% decline in performance from age 40 to age 65. Evidence comes from bicycling time trials, and 5K and 10K runs. Decline over time is faster for occasional athletes and the sedentary.

There is hope. For the approximately ten million U.S. adults who have sarcopenia, i.e., age-related muscle loss, a supervised program of resistance exercise can partially reverse muscle weakness and improve quality of life, even when started late in life. Vitamin D at 1,000 IU/day (many elderly are vitamin D deficient) has been proven to reduce the risk of injury from falls by 20 percent. Flavonoids, chemical compounds found in foods such as red wine, dark chocolate, green tea, nuts, and some types of dark-colored fruits, and are thought to contribute to artery health.

"Article Directory by Category" lists eight other health-related topics, such as recovering from donating blood (March 2011).

Thursday, February 9, 2012

Hibernators Large and Small

Winter strategies for species without central heating span migrating, toughing it out and hibernating. That last option - damping down the metabolism - has been taken up by species ranging in size from large to small.

Black Bears: In the late summer and early fall these New England neighbors double to triple their food intake in order to add an inches-thick layer of body fat. Come fall the bears find a confined space for a den such as under the trunk of a fallen tree. The den offers some physical protection from the elements, but is not warmer than the outside temperature. Body temperature drops to about 90F degrees and heart rate slows to ten beats per minute (bpm). This semi-hibernating state last for months, but if disturbed a black bear can achieve a fully roused state within minutes. One large puzzle is how bears manage the winter-long rest without needing to eat, drink, urinate or defecate, nor suffer from the bone loss and muscle atrophy humans would undergo from the equivalent months of bed rest.  

Woodchucks: Also known as groundhogs, these mid-sized mammals are true hibernators. They gain thirty percent in body weight, almost entirely as fat, before entering a den in late October to begin a months-long state of torpor: body temperature dropped to 40F degrees, heart rate dropped to about five bpm and breathing rate decreased to less than one per minute. Roughly every two weeks the hibernating animals rouse to full awareness, go to the bathroom and undergo a day or two of normal sleep in order to catch up on their dreaming (confirmed by rapid-eye-motion type sleep). If this coincides with February 2nd then it is Groundhog Day. One puzzle: what late summer signal triggers the beginnings of over-eating to gain all that weight?

Chipmunks: These ground-living relatives of squirrels add some body fat in the fall and store caches of food – primarily seeds – in their underground burrows. The burrows extend below the frost line. Chipmunks enter an intermittent hibernating state. Body temperatures approach 40F degrees. Heart rate slows from 200-300 bpm to under 10. Every few days the chipmunk warms back up to close to 100 degrees and becomes active. Separate areas of the den serve as food larder, bathroom and bedroom. Come late winter the males will begin to surface-wander in search of dens of females. One consequence - spring litters tend to have only one father, whereas summer litters are likely to have multiple fathers.  

Yellow Jacket Wasps: In the fall the virgin queens leave their mother's nest to mate. Like honey bees, yellow jacket queens will mate with 3-10 males. The males die. The fertilized females hibernate under tree bark on in another dry place. Insects have a few hibernating strategies to choose from. Some synthesize glycerol (antifreeze) in order to lower their freezing temperature. Some select a dry place to stay and supercool without ice crystal formation. Others allow themselves to freeze, and in fact synthesize freeze-promoting proteins, with the idea that freezing s-l-o-w-l-y and then remaining frozen all winter reduces risk of large ice crystal formation which would poke holes in cells. Yellow jacket queens employ glycerol and supercooling. Coming out from under hibernation is not triggered by an internal signal. Rather, the yellow jacket queens depend on the warming temperatures of spring to bring them back to life.

Warmer winters in Alabama and other south eastern states have led to an interesting phenomenon. Rather than the nest dying from the cold there is enough food and warmth to get through the winter as an active colony. Come spring, the colony re-expands, and related daughter queens set up housekeeping next door. So instead of scattered annual colonies there is a multi-year, condominium-like complex making up a super-colony of tens of thousands of related but not genetically identical yellow jacket wasps.