What Are Those Lines On The Duxbury Marshes? Theory 2: Mosquito Control

The Great Salt Marsh, east of the Cut River, Duxbury MA

We did a whole article yesterday about the man-made lines in the Duxbury marshes, an article where we thought we had figured out a mystery. Then, a guy on Facebook steered me towards the possibility that I was 10000% wrong, and I became convinced that he and not I was correct as I did additional research.

Now, I'm torn between a mea culpa tone, and just making the old article be about about salt marsh hay. Either way, my man (I'll leave his name out, unless he wants to claim credit) gave me a hella tip, and I got in another few hours of fun research.

Historians have a different definition of fun than most people operate with, I just thought I'd work that in somewhere.

We were blaming those lines in the Duxbury marshes on salt marsh hay harvesting, but then some Old School guy pointed out that he watched canal work being dug in the marshes in the 1950s. He put the focus on mosquito control efforts. The more I read about Massachusetts mosquito control history, the more I knew that he was right and that I had just needlessly wasted 7500 words.

Let's straighten out the mess I caused yesterday with the mess I will create today.

Massachusetts, and Duxbury in particular, have a lot of salt marsh. These marshes fill and empty to some extent with sea water. During a full moon tide, Duxbury's marshes overflow their water into the surrounding neighborhoods. Daniel Webster has writings about the full moon tide encroaching upon his garden.

The marshes fill and empty with the tides, but it is not a 100% complete expulsion of water with the outgoing tide. A lot of water remains pooled in the marsh after the tide recedes, and that standing water is the breeding ground for mosquitos.

"Marshfield Meadows," Martin Johnson Heade

Several things went down around the same time, some involving Duxbury directly and some more national or worldly in scope... and they led up to the marsh getting lined out in this theory which I'm exploring.

First, a series of construction projects made the beaches inhabitable. Chief among them were the construction of a dyke in Green Harbor, the installation of a series of jetties in Green Harbor, and eventually the seawall that lines the beaches.

The dyke changed the course of the Green Harbor River, which used to empty either closer to Duxbury or in Duxbury. Not long after the dyke (1872, I think) and the jetties (1898) went up, cottages began to spring up on the northern end of Duxbury Beach.

The cottages were indicative of a change in American social behavior, as oceanfront recreation became popular. While the aristocracy had been at the beaches for centuries (I doubt that The Great Gatsby bought his oceanfront mansion from a clamdigger), regular folks didn't or couldn't go to the beach for laughs. They didn't even invent swimsuits until society wasn't so afraid of a women's shin being displayed in public.

Bourne, MA

Even after they invented cars and trains, they didn't get around to running highways or tracks down the South Shore until as late as the 1950s. The highways, and the newfound desire to flee the teeming cities, pretty much wrote the check that paid for the Irish Riviera. They also turned Duxbury from a farming community to a bedroom community of Boston commuters.

At the same time, they were building a Canal in Panama. The French had tried, and were losing 200 people a month to malaria. The US took over, and they eventually were able to identify the skeeter vector and nearly eliminate it... granted, with some ugly environmental effects.

The US had their own mosquito problems. Yellow Fever outbreaks happened in New Orleans and Florida, Dengue Fever was going on in the hundreds of thousands from Florida to Texas, forms of encephalitis ranged from California to Cape Cod (Massachusetts lost 38 humans and 200+ horses to something spelled sort of like Eastern Equine Encephalitis in 1938), and it also itches really badly when they bite you.

Mosquito control methods that worked in the former Colombia were imported into the USA, and implemented all across the nation. Some things were simple, like putting screens on your window or using a topical repellent. Others, like the removal of standing water in which skeeters breed, ranges from simple to arduous.

"Simple" means "kicking over buckets that collect rainwater." "Arduous" means "draining 1000 acre salt marshes."

The marshes were formerly very important to local commerce, allowing for settlement to be built. No hay, no cows, no Duxbury. However, the industrial age and the automobile era ended the importance of salt marsh hay. The deathblow was the transition of Duxbury from a farming region to a bedroom community.

So, you have throngs of people moving out of the cities, even just for the summer, and they are moving into Mosquito Village. Fortunately, they were doing so when means to combat mosquito-based illnesses became prevalent. Let's even throw in the added bonus of Great Depression WPA busy work.

Marshfield Meadows (redux), Martin Johnson Heade

Prior to DDT ( I mean the insecticide, not Jake The Snake's infamous finishing move, which was actually named for the poison), the best way they had to fight mosquito infestation was to drain the bogs and swamps and marshes.

This is where we get to the lines in the marsh.

By 1930, 90% of the marshes on the Eastern Seaboard had been drained to some extent. Duxbury, if this current theory is correct, used a method where small channels were dug, all running into tidal rivers and tributaries. In theory, they drain the standing water from the marsh and eliminate the mosquito breeding grounds.

Looking at the picture above, that does seem to be the case. Each line cut in the marsh runs to one of the tidal creeks. It looks like a clear win for the mosquito control theory, as Duxbury hosts one of the largest tidal marshes in the area and would have merited immediate attention from the skeeter control people.

Whether or not they dug out channels that were already in the marsh from the salt hay days, I can not say. The channels may have been cut to irrigate the meadows in the salt hay days (salt hay harvesting also needs the channels for the marsh to drain with the tide, as well as to float the product to the other side of the bay), and then re-dug to drain the standing water that breeds skeeters.

I hope there's not an Option C on the menu, because I've wasted a lot of keystrokes on this topic.

The Great Salt Marsh, Duxbury MA

There were some bad side effects. This was a brutal assault on a natural resource, and all of the Liberal superpowers were used up getting the government to pay for the avoid-starvation busy work.

The mosquito population was blunted. You can still see a mosquito here and there, just not in the numbers you'd expect living next to a thousand acre salt marsh. We should be swarmed. The fact that we aren't tells you a lot about how well it worked.

The drainage did nothing to blunt the greenhead population, nor that of the midgies. Greenheads lay their eggs on land, not in water, and the drainage was like a baby boom to them. The traps you can still see out on the Duxbury marshes are designed to capture the greenheads who flourished after the removal of the competitor skeeters.

The meadow was devastated. God and Mother Nature had sort of agreed on a water/land balance, and the drainage project blew that out of the water. A formerly abundant meadow was now a relatively barren wasteland... still ecologically important, but with far less impact.

Plants accustomed to a certain water level died out. Birds accustomed to mosquito dinners died off. Fish who would feed on the skeeter larvae starved, and the fish who ate those fish starved, and the effects were felt up the food chain to my many fruitless childhood fishing trips in the 1970s.

Duxbury, MA, from Bill M

By in my childhood, other than a few heron and a solitary owl, most of the marsh life was made up of greenheads and horseshoe crabs.

At least one study found that waterfowl, formerly abundant on the Duxbury marshes, had fled the region. It stated that the same area was now "dry, and devoid of birds." While sucking the Marsh out of Marshfield, the project also drove the Dux out of Duxbury.

I did, during my travels, get to West Island in Fairhaven. I saw a similar marsh with a similar to-the-creek channel pattern. The marsh was way too small to work commercially, as it would have fed maybe one horse. It would, however, have bred a lot of skeeters.

As much as I like the salt marsh hay theory, I have to go with the mosquito control theories in the end. I can hack yesterday's article into a salt marsh hay piece.

So, unless someone from the salt marsh hay lobby has a higher bid, I'm going to blame those lines on mosquito control programs from the first half of the 20th Century. 

I'd also blame the out-of-context mud flats which dot Duxbury Beach on the mud-dumping from these insect control programs. The engineers dumped the mud they dug out for the channels over the dunes and onto the beach, where it wouldn't seep back into the freshly-dug channels with the next flood tide.

The mud flats could also be the result of the Green Harbor channel dredging, that's a mystery for another day. For all I know, the whole of Duxbury Beach is a marshy mud covered by centuries of washed-down sand. Our mud flats may just be those trying to assert themselves.

We still love the Salt Marsh Hay people, however. We'll end with a pic of them in their faithful gundalow, bringing home the bacon rakin'......courtesy of the Duxbury Rural And Historical Society.