Category: Analysis

Anything that I have tested empirically, or explain with detailed calculations, or just generally bother to get all the facts straight.

Post #1804: Speed limits in Fairfax County, how much slack?

 

Background:  A speed limit + 10 rule?

Source:  WTOP.

There was an article today on the local news-radio website (WTOP) regarding speeding in school zones.  I took note, because I routinely drive through one of those zones where Fairfax County VA operates speed cameras.  The zone is clearly marked, and you’d have to be blind to miss it, as shown above.

And yet:

In total, 23,431 cars were caught going 10 or more miles per hour above the speed limit in April, May and June combined.

I supposed I should be impressed by the sheer numbers.  But instead, a completely different figure caught my eye:  They only ticketed folks for going at least 10 MPH over the limit.

First, I thought it was intemperate of the reporter to note that exact figure.  Anybody reading the article realizes that there’s no risk of a ticket at anything up to the posted speed plus 9 MPH.  So, presumably, if generally known, that now becomes the de facto speed limit.

But second, I’d heard that same figure before, a few years back, in a discussion of red-light cameras and speeding cameras in Vienna, a town in Fairfax County.  There it was phrased as “we don’t ticket unless they are going at least 11 MPH over the posted limit.”  The explanation given at the time was that Fairfax County courts would not accept cases for any infraction less than that.

Is that the rule here, and if so, why?

Short answer is, yes and no.

In theory, by Virginia statute, you can get ticketed for traveling one mile an hour over the speed limit in a residential area.  This is my interpretation of § 46.2-878.2 of Virginia statute, which says :

Operation of any motor vehicle in excess of a maximum speed limit ... in a residence district of a county, city, or town ... shall be unlawful and constitute a traffic infraction punishable by a fine of $200, in addition to other penalties provided by law.

The black-letter law provides no slack.  If you’re in a residential district, on a highway (meaning, in Virginia, any public alley, street, road, or highway), and you’re going a mile over the limit, you can, in theory, be ticketed and will owe a minimum of $200.

Except that the law spells out a different set of penalties for drivers caught by speed cameras in school zones.  My interpretation is that because the process is, in effect, automated, they cut drivers a lot more slack than they would if they’d been pulled over, in person, by a uniformed officer.

In the case of speed cameras in a school zone (§ 46.2-882.1), emphasis mine:

1. The operator ... shall be liable for a monetary civil penalty ... if such vehicle is found ... to be traveling at speeds of at least 10 miles per hour above the posted ...  speed limit ... .  Such civil penalty shall not exceed $100 ...

...

4. Imposition of a penalty pursuant to this section ... shall not be made part of the operating record of the person upon whom such liability is imposed, nor shall it be used for insurance purposes in the provision of motor vehicle insurance coverage.

The bottom line

There appears to be no hard-and-fast rule regarding ticketing for how much “slack” you get, speeding in a residential area in Virginia.  The plain language of State law in Virginia law says that if you exceed the posted limit, you can be ticketed.  I believe that pre-empts any local law, as we are a Dillon Rule state.   That is, local governments can only make their own rules where the Commonwealth grants them permission to do so.  And nothing in Commonwealth statute appears to do that, with a few limited and explicit exceptions spelled out in the law.

Except that “ten miles over the limit” is written into law, in Virginia, for speed-zone cameras.  There, the Commonwealth leans heavily in the direction of protecting drivers’ rights, and avoiding Big Brother information harvesting.  So, in exchange for what is basically an automated process, you face a small fine.  There’s a monetary penalty, but (as I read it) no points on the license.

Extras for experts:  Two non-obvious reasons not to speed in residential areas.

First, if you are speeding, in Virginia, you lose any claim to having right-of-way.  So if some bonehead does something to get you in a car accident, where you had the right of way, but you were speeding at the time … tough luck.  You cannot claim right-of-way while you are speeding.

§ 46.2-823. Unlawful speed forfeits right-of-way.

The driver of any vehicle traveling at an unlawful speed shall forfeit any right-of-way which he might otherwise have under this article.

The reason for that is pretty clear.  Traveling at excess speed makes it difficult for other drivers to judge whether or not an accident will occur.

We had a horrific accident in this area, last year, that is a classic illustration of that.  The culprit was a bozo who was driving a BMW about 80 MPH in a 35 MPH zone.  His car got struck by a car turning left, and his car subsequently jumped the sidewalk and killed two high school student who were on the sidewalk, walking home from school.

Normally, the car going straight has the right of way.  Should the car turning left have therefore been charged with the accident, for failure to yield right-of-way?   I don’t think any sane person would suggest that.  If nothing else, on a curved road, excessive speed of that magnitude more-or-less prevents drivers from seeing you coming in time.  The accident was entirely the fault of the speeding driver.

Second, if you speed significantly in areas with red lights, you will run red lights. 

Not may, will.

This point is courtesy of Road Guy Rob on YouTube.  Yellow light duration is set based on expected traffic speed.  (Plus regional variation, I guess).  High-speed roads have long yellow lights, low speed roads have short yellow lights.  In both cases, the length of the yellow allows drivers that are far from the intersection to stop before the light turns red.

If you drive at high speed, on a low speed road, there will be a stretch of pavement, and a rage of excess speeds, so that if you see the yellow light while you’re in that zone, you will literally be unable to avoid running the red.  That’s because, between your reaction time and the car’s stopping distance, your car will travel much further than the engineers who set up the light expected.  If you are within just the right range of excess speeds, if you see the light turn yellow, you both a) can’t make it through the intersection before the light turns red, and b) can’t stop before entering the intersection.  No  matter what you do — hit the brakes, hit the gas — you go through the red light. 

And so, at some level, excessive speeding and running red lights go hand-in-hand.  There’s a certain pleasing symmetry to that.  My guess is, the folks who don’t care about the first, don’t much care about the second either.

Post #1803: Why are fine particulates (PM 2.5) so variable? It’s over my head.

 

One thing I’ve noticed about the AQI for particulates is how variable it is.  On any given day, my local hourly estimate from Accuweather will differ significantly from the EPA’s Airnow map.  Which, in turn, differs from readings just a few miles away.  For example, above, my AQI for particulates (as of 1 PM 7/6/2023 is either 63 (Airnow) or 33 (Accuweather).  Or somewhere between.

And readings within a few miles go as low as 13.  At the same time, the seemingly accurate meter I just bought shows “9”, sitting on my back screen porch.

At first, I chalked that up to instrumentation.  Maybe particulates are hard to measure, and what I’m looking at is more-or-less instrumentation error.

Because, serious, how could the air be so different, just a few miles away?  If I were to take some other measure of the atmosphere — temperature, humidity, pressure — it would vary smoothly over vast areas.   E.g., if it’s 90 degrees here in Vienna, VA, there isn’t going to be a pocket of 45 degree air five miles away in the City of Fairfax.  Yet you see that sort of apparent PM 2.5 disparity all the time.

So I thought, it must be poor instrumentation.  Then I bought a cheap air quality meter, noted above.  Not only are the readings stable from hour to hour, they are frequently in good agreement with the Accuweather numbers.  They clearly respond to ambient conditions in a hurry.  (The 4th of July fireworks briefly sent the meter into the “purple” AQI range, consistent with predictions from the Airnow map.)  The stated accuracy of the PM 2.5 measurement is +/- 10%.  All that, from a device that measures all five of the key air pollutants and costs under $75.

So, this isn’t due to instrumentation error.  Or shouldn’t be.  You can get reasonably reliable PM 2.5 measurements with a cheap off-the-shelf device.

Maybe my local variation is due to the presence of large local point-sources of PM 2.5.  But, to a large degree, we have no large point sources of particulate emissions in this area.  Largely because we are almost devoid of industry, in the DC area, and our power plants are (mostly) located outside of the metro area.

Which also matches my observation, because it’s not as if one area is consistently dirty.  It’s that the readings consistently vary a lot from place-to-place in this region.

So why do the PM2.5 readings in my area appear to be so highly localized?  Is there really that little mixing of the air between PM2.5 emitters, and local air?

Trying to understand how air mixes — a fool’s errand.

After about an hour of looking, I’m going to say that short of getting a graduate degree in atmospheric science, this ain’t gonna happen. 

It’s surprisingly complicated, but the joker in the deck is “turbulent mixing”?  Once I found out about that, I realized it was time to call it quits on trying to understand this.

First, physicists distinguish “bulk flow” (e.g., a breeze) from “diffusion processes” (molecules or particles moving through still air).  In this case, the latter would be the movement of water molecules or fine particulates through still air.

So, smoke spreads out because it 1) blows smoothly downwind, and because 2) the particles diffuse outward into surrounding clean air.

That said, it also spreads due to 3) turbulent mixing.  Any time the flow of air is not smooth (laminar, or layered), turbulent mixing is said to occur.  This sort of mixing can apparently distribute that smoke fully and more-or-less uniformly in the adjacent clean air.

Turbulent mixing occurs a lot in the atmosphere.  I’m pretty sure that it occurs at the level at which clouds form above the ground.  It occurs within clouds.  I occurs if sufficiently strong wind sweeps past fixed objects, e.g., tree branches.  And so on.  Anything sufficient energetic will kick the flow of the atmosphere from laminar flow to turbulent flow and turbulent mixing.

The bottom line is that there is no back-of-the-envelope way to determine how well PM 2.5 (including smoke) typically mixes into the surrounding atmosphere.  In the end, it’s all empirical, and depends on how hard the wind is blowing horizontally, how turbulent the atmosphere is in vertical profile, and so on.

Presumably, both water vapor and PM 2.5 move at the same speed, and mix at the same rate, when it comes to bulk transport and to turbulent mixing.  In both those cases, they are merely being carried along by the surrounding air.

But PM 2.5 diffuses a lot less rapidly than (say) water vapor.  A theoretical rule (via Einstein and Stokes) is that rate of diffusion is inversely proportional to the radius of the particle trying to diffuse.  Getting hold of some data (but not showing the calculation), that suggest that PM 2.5 diffuses about a thousand times more slowly than water vapor.

Diameter of a water molecule seems to be given as 2.75 Angstrom, where an Angstrom is 1/(10^10) meters.  Ah, round down to 2.5.  But PM 2.5 is in microns, or 1/(10^6) meters.  This means PM2.5 particle is about 10^4 = 1000 times larger than a water molecule.  Thus under this  simple theory, water (humidity) diffuses through still air roughly a thousand times faster than a PM 2.5 particle would.

At the end of the day, I have no clue whether that matters or not, with regard to widely varying PM 2.5 readings across my area. 

All I know is that even without big local point-sources of PM 2.5, it’s common to see big difference in (what appears to be) actual PM 2.5, across different locations in my area.  Whereas for other parameters of the atmosphere — temperature, pressure, humidity — true local variation in those quantities is tiny.

Seems kind of crazy to worry about it, but there has to be some good reason why this aspect of the atmosphere is so qualitatively different from others.

Maybe Hawaii wasn’t just a nice place to hang out.

Maybe my only clue comes from the Keeling curve (above) and how that is measured.  When Keeling started measuring atmospheric C02 in the late 1950s, he established his laboratory on the windward side of Mauna Loa.

And found average atmospheric C02 around 315 PPM.  Currently, it’s around 422 PPM.

But the point is why he chose that locale.  His goal was to get “well mixed” atmospheric gasses, and, apparently, having circa 6000 (?) miles of open ocean to windward was just the ticket for getting that.

By contrast, you can frequently find city air with C02 levels in the 1000-PPM range, near congested roads (reference).  That air hadn’t had a chance to get mixed with the rest of the atmosphere.

So, maybe Keeling located there for some reason other than it’s being a nice place.  Maybe you really need that much distance to ensure uniform mixing.  And maybe the mere 500 miles or so between me and the nearest Canadian mega-fire isn’t enough to ensure uniform mixing of the air.

So I’m guessing that the atmosphere doesn’t mix all that uniformly.  For whatever reason.  And that the small-area variation in PM 2.5 is true.  And that I should not expect it to get any smaller as the summer progresses.

Post #1803: What’s normal for PM 2.5 in my area?

 

Currently our AQI is a mere 87, for fine particulates (PM 2.5).  That’s a relief.  Just a normal amount of air pollution.

Or is it?  I’ve kind of lost track of what was normal for my area.  It’s not like I paid attention to the AQI for most of the past decade.

So here, for Fairfax County, VA, I’m posting a table of AQI statistics, for PM 2.5. based on the period 2010-2022.  Just so that I can refer to it as needed.  Briefly, only 1% of days exceed the 99th percentile.  Half of days exceed the 50th percentile.  And so on. Continue reading Post #1803: What’s normal for PM 2.5 in my area?

Post #1802: How good is my car’s interior (cabin) air filter?

 

There’s little in the way of hard data available for car air filters themselves.

That said, the clear consensus of informed opinion is that in newer vehicles, setting the AC to recirculate will remove most of the fine particulates (PM 2.5) from the cabin air in a matter of minutes. Continue reading Post #1802: How good is my car’s interior (cabin) air filter?

Post #1800: Not the smokiest month on record for Fairfax County, VA

 

Along with much of the eastern U.S, we’re living through another round of air pollution alerts here in Northern Virginia. Best guess seems to be that those Canadian forest fires will be burning for months yet, so this will be occurring sporadically all summer.

I decided to see how the current situation looks, compared to historical air pollution levels in this area.  To do that, I downloaded a little over two decades of daily data on fine particulates (PM 2.5) in Fairfax County.

I got some real surprises.  Mainly, as high as the PM 2.5 levels have been, this June, that’s not a monthly record.  In the 2000s (and presumably earlier) we routinely exceeded the monthly average level of PM 2.5 that we’ve seen in this smoky June 2023.  Best guess, that was due to a toxic interaction of air-conditioning and coal-fired electrical generation.

It is exactly as I recall.  Summertime air quality in the DC area was always bad.  It had only recently gotten materially better.  And then, along came these fires.

Details follow.

 

Long-term trend toward cleaner air

The EPA allows you to look up historical AQI data, at this website.  For Fairfax County, and PM 2.5 (fine particulates), the earliest complete year of data is 2000.  So that’s where this analysis starts.  (Although the cutoffs for the AQI scale changed over this period, it appears that the website delivers AQI data uniformly using the current cutoffs.)

Source:  Analysis of daily data from EPA website cited above.

The air got materially cleaner over this period.  That’s clearly visible when I plot the annual average AQI for fine particulates (PM 2.5) from 2000 to June 2023.  Back in 2000, the average was a bit over 50.  By the time you get to 2015, the average was a bit over 30.

Best guess, around here, that was mostly a consequence of replacing coal with natural gas in our electricity generation mix.  In 2000, half the power consumed in Virginia was coal-fired power.  By 2020, that had fallen to just 4 percent.  Almost certainly, the oldest and dirtiest plants were retired first.  But this is also the era when regulation of particulates from diesels went into effect.

Source:  Underlying data from the U.S. Energy Information Administration.

But August was always hazy, hot, and humid.

So far so good.  But here’s where things turn weird.  Let me now plot the same data as monthly averages, from January 2000 to June 2023.

Source:  Analysis of daily data from EPA website cited above.

Surprise.   Every year, in the 2000s, in the heat of summer, monthly-average particulate levels rose to the level they reached for June 2023.

I didn’t expect that.

I knew that we always had terrible ground-level ozone in the summer, but there are good reasons for that.  Ground level ozone forms from the interaction of oxides of nitrogen and volatile organic compounds, acted on by sunlight and heat.  We naturally got peak ozone during the peak of the summer season.

But what caused these August peaks in PM 2.5, that somehow was fully-phased-out by 2010 or so, I cannot quite fathom.  Because July and August are the peak months for electricity use (in the U.S. and presumably in Virginia), I’m guessing this also has to do with electricity generation and the change in the generation mix of the Virginia grid.

And, by inference, about half the improvement in the yearly averages was due to getting rid of those July-August peaks.  You can see that the annual minimums declined from about 40 to about 30, or half the decline in the annual averages.

My only real point is that, two decades ago, every summer, monthly average particulate levels in this area exceeded what they were in June 2023.

Plot the worst day in each month.

When I plot the worst day in each month, then June 2023 finally stands out against the historical background.  In the 2000s, we routinely had Code Orange y AQI days for fine particulates (AQI > 100).  But we never had a Code Red day, that is, AQI over 150.  By the 2010s, Code Orange days had become rare.

In any case, since the start of recordkeeping in 2000, we hadn’t had anything close to the AQI of 198, for particulates, that we saw in June 2023.

Summary:  We’re just having a series of bad days.

So that’s how to characterize this situation around here.  We have occasional days with incredibly awful air quality (for particulates), compared to historical averages.  But the average for the month isn’t even as bad as it was back in the days of air-conditioners running on coal-fired electricity.

Post #1799: Forest fire smoke, yet again. How good an air filter do you actually need?

 

In a nutshell:  There is no hard cutoff.  More air filtration is better.  But there are clearly diminishing returns to buying the ultra-high-end air filters.

The bottom line is that, when it comes to the current air quality alerts, some air filtration is a whole lot better than no air filtration.

Continue reading Post #1799: Forest fire smoke, yet again. How good an air filter do you actually need?

Post 1798: Forest fire smoke and easy air cleaning.

 

With smoke from the Canadian forest fires continuing to generate air pollution alerts in the U.S., my wife suggested that I re-up my articles on using a box fan as an air cleaner.

This is a re-telling of Post #1792 and Post #1794.  Refer to those posts if you want more background information.

Three simple points

Point 1:  A standard 20″ box fan and a high-end 3M Filtrete HVAC filter together make a simple and effective air cleaner.  Get a 3M 1900 filter (rated MERV 13), place it on the back of the fan, and turn the fan on.

The key here is that the 3M electrostatic filters produce little “back pressure” or resistance to air flow.  That’s why you can have the low-powered fan draw air through that filter and still have significant air flow.

You can do the same thing with standard high-resistance MERV 13 filters, but you would need to construct a “Corsi Box” to provide enough surface area.  That is, tape four together into a hollow box, to provide enough surface area to allow for adequate air flow.

The 3M filters are expensive, but in my experience they last for months.  Arguably, this being almost July, you’d only need one for the entire summer.

 

Point 2:  This is more effective than a typical room-sized HEPA filter.  The reason is that with heavily-polluted outdoor air, filtering a lot of air reasonably well (fan + filter) beats filtering a small amount of air extremely well (HEPA unit).

Above is the labeling on that Filtrete (r) 1900 filter. In a single pass through the filter, it removes

  • 62% of the tiniest particles (0.3 to 1.0 mircons)
  • 87% of the mid-sized particles (1.0 to 3.0 microns)
  • 95% of the larger particles (3.0 to 10 microns).

That’s nowhere near as good as a HEPA filter, which removes on-order-of 99.97% of all such particles in a single pass.

So why does the fan + filter win?

First, outdoor air infiltrates into indoor spaces at a fairly rapid rate.  Typical tight older construction has one air exchange per hour.  That is, every hour, enough outdoor air enters the building to replace the entire volume of indoor air.

In the current situation, that means smoky outdoor air is more-or-less pouring into your living space, continuously.  Even with the windows and doors shut.

Second, a box fan moves a lot more air per minute than a typical room-sized HEPA unit.  A box fan on high can move about 2000 cubic feet of air per minute.  Depending on the fan, a box fan on low can move on order of 1000 cubic feet per minute.  A typical room-sized HEPA unit might move just over 100 cubic feet per minute.

The end result is that the slower HEPA filter can’t keep up with the steady inflow of dirty air.  Or, more properly, can’t keep up as well as the fan-and-filter combination.

On the left, you see the results of a numerical simulation of the two types of filtration.  Left is the box-and-filter, right is a typical HEPA unit.  Horizontal axis is time, vertical axis is the density of particulates in the air.  (See prior post for full details of simulation).

The equilibrium level of particulates in the room is vastly lower with the high-volume, lower-efficiency filter (left graph above).  Why?  Because the slow pace of the HEPA filter (right graph) can’t keep up with the level of outside-air infiltration that is typical in older construction.

Point 3: Availability.  As we learned during the pandemic, if there’s a sudden surge in demand (e.g., for N95 respirators), the shelves are soon stripped bare.  So if everybody goes out looking for an air cleaning device, those will soon become unobtainable.

As of today, my local Home Depot has well over 100 20″ box fans in stock, on the floor, ready to be purchased.  By contrast, they have just five room-sized HEPA units in stock. 

Which makes sense.  Those fans are commodity items costing about $25 each.  The Honeywell HEPA unit, by contrast, goes for just about $300.    Home Depot couldn’t afford to keep 100 of those in stock, on the off chance that there might be a run on air cleaners.

Summary

Sometimes, simple and cheap is what you want.  In this case, a box fan and a 3M 1900 air filter together cost much less than a room-sized HEPA filter.  And in this situation — where you are trying to filter pollution arriving from outdoor air — the much higher air flow of the fan-and-filter combination actually works better than a typical HEPA air cleaner.

Nothing prevents you from dealing with this problem by wearing an N95 respirator inside.  But note from the simulation above, the fan-and-filter combination provides air that is almost as clean as you would get, breathing through an N95 respirator.  So you get almost the full benefit of that, without the hassle of wearing a mask 24/7.

As a bonus, while the mask protects your lungs, the fan-and-filter combination protects both your lungs and your eyes.  If eye irritation is an issue for you, filtering the indoor air is the only way to go.

Post G23-031: The iron law of back-yard gardening.

 

Nature doesn’t merely abhor a vacuum.  Nature is a vacuum.

You name the delicious food plant that you’d like to grow, and I’ll find a pest that will hoover it up before you can.

Thus, the Iron Law of Backyard Gardening:

Anything that can be eaten, will be eaten.

Plan your garden accordingly.

Machine-gun emplacements optional

I had a friend over yesterday, during which time I showed him the various deer defenses for my garden area.  These are pretty much in line with my original garden plan for the year (Post G23-009), and include:

  • A square enclosure,
  • fully surrounded by a 6′ trellis,
  • which is in turn surrounded by an electric fence,
  • with motion-activated water squirters inside,
  • plus a handful of Wireless Deer Fence units,
  • a motion-activated light.
  • And some chemical deer repellent, held in reserve for the fall, when the deer get really aggressive.

I can see where some might think this is a bit extreme.  But, so far, this seems to be keeping the deer out of my garden. I’ll settle for that.

Outside the defensive perimeter, the only survivors are plants that deer won’t (typically) eat.  This year, that’s mustard, various “deer-proof” flower mixes, marigolds, and zinnias.

I don’t plant that because I’m particularly fond of it.  I plant it because the deer aren’t.

A multiple-choice question for testing your gardening maturity.

When you consider planting sweet corn in your garden, the first thing that comes to mind is:

  1. How great fresh corn will taste.
  2. Where’s the best spot to put it.
  3. How to keep the @#$)$(# squirrels (raccoons, deer) from eating it.

Score your gardening maturity level as follows:

  1. Novice
  2. Intermediate
  3. Veteran

Why?  Because if you don’t have a good solution to c) above, a) and b) just don’t matter.

This is no mere academic exercise.  I’ve been thinking about planting a little Silver Queen sweet corn in that garden.  It ticks all the boxes for something I’d like to grow.  My whole family likes it, and we can’t buy it around here, not even at the local farmers’ markets.

The old me would have simply cleared some space, planted some seeds, watered and fertilized according to directions … and hoped.  But in the squirrel-infested suburbs, I suspect that all I’d be doing is buying myself a ton of heartache down the road.

Why?  See the Iron Law of Backyard Gardening above.

Probably the existing electric fence etc. will keep the deer out.  Maybe the squirrels won’t recognize it as food.  Maybe the local crows won’t discover my tiny batch of corn.  Maybe my cucumber beetles (which double as the Southern Corn Rootworm) won’t find it.

But when I add all those up, the likelihood that I’m going to get to eat that sweet corn is pretty slim.  Absent some fairly strong and pro-active defensive measures.

Before I put a seed in the ground, I have to work out how am I going to keep the squirrels off my corn.

All else is folly.

I dis the sisters

The first thing I came across is the traditional “Three Sisters” planting method, above.  It’s actually pretty sophisticated, in that you don’t just randomly inter-plant corn, beans, and squash.  Instead, the squash is planted to form a defensive ring around the corn/beans plot.  With the idea being that (e.g.) raccoons and squirrels don’t like pushing through the prickly squash leaves, and so will leave your corn alone.

Funny thing about it, though.  As with so many things for the home garden, a lot of people repeat that story.  Almost nobody tests it.  And almost nobody reports the results of that test.  I found exactly one individual who tried it, and said it was a miserable failure for keeping squirrels out of the corn.

And I believe that, because my squirrels had no problem at all waltzing through my cucurbits in order to gnaw on my winter squash and pumpkins.  What finally put a stop to that was wrapping the pumpkins in floating row cover, which, apparently, led the squirrels to forget that there were pumpkins there.  Or something.

(Upon reflection, it’s entirely possible that modern squash varieties are a lot “tamer” than what Native Americans would have grown.  A thornier squash might in fact make a pretty good barrier against squirrels and raccoons.)

So the idea that a row of squash plants is going to deter them from going after a prize like sweet corn, that’s just fantasy.  Might work somewhere, but I’m not staking my corn crop on it.

And then for every other “home remedy” approach to keeping squirrels off corn, you can find plenty of people who tried it and had it fail. Hot pepper powder.  Peppermint oil.  Chemical repellents.  And so on.

Near as I can tell, my options are to grow my corn in a squirrel-proof cage (including six inches under the soil, and a fence roof on top), or produce enough of an electric fence/net that the squirrels can’t get over it to get to the corn.  Or, alternatively, exterminate my local squirrels, or use a squirrel-hating dog as a garden watch dog.

Given that I already have an electric fence driver, I believe that if I go through with growing Silver Queen, I’m going to surround it with a mesh-type electric fence.  If I can find or make one cheaply enough.

This is my gardening life

In hindsight, this really and truly reflects how I garden now, after just four years of intensive back-yard gardening.  Each year, what I grow is a smaller and smaller subset of what I’d like to grow.

My vegetable garden increasingly consists of plants that can fend for themselves, and those that I can feasibly protect.  Poisonous leaves (potato, tomato)?  Perfect.  Painful thorns (cane fruits)?  Ideal.  Or plants that are mostly left alone, as long as I can keep the deer off them (peas, beans, sweet potato, cucurbits).  That’ll do.

But sweet corn?  No natural defenses.  Attractive to everything that flies or walks through my yard.  Tall enough that fencing it in is a chore.  Plus, plentiful insect pests.

With sweet corn, it’s not a question of whether something will eat it.  Just when, and how much.

If I can figure out some cheap and feasible squirrel defense, I’ll give it a try.  But if that’s a crash-and-burn, I’ll buy my corn at the store just like everybody else.  And move on.

Post #1797: Rethinking mail-in voting in Virginia

 

I’m not one to bash the USPS.  For two decades, my business-related financial transactions went through the mail.  The only time a check ever got “lost in the mail” is when a client sent it to my prior address.  To within rounding error, in all that time, the USPS had more-or-less a 100% success rate.

But for this post, I’m going to make an exception. Continue reading Post #1797: Rethinking mail-in voting in Virginia