Talk:Rod (unit)

Picture?

What does that picture have to do with the rod? Anyone know? Anyone feel like they are confident enough to take it down? JesseRafe 03:35, 24 April 2006 (UTC)

I'm not sure, but I think the bar on the sign might measure one rod. It doesn't seem immediately relevant, though. Vashti 18:19, 25 April 2006 (UTC)

I'm not sure even, it's plausible that "Ruthe" could mean "Rod," but then that sign would only mean "One Prussian Half Rod"... and who cares what a Prussian Rod is, wouldn't all countries have different local measures back in the day? I think it should be deleted. JesseRafe 04:30, 26 April 2006 (UTC)

Well, imperial measurements were all different wherever you went, but this article ought to be (and is, IIRC) about everywhere's rod. If we could establish the significance of the sign it might be a nice illustration of the concept. Any fluent German speakers out there who could ask the German Wikipedia for help (or even help, but that might be a bit optimistic for something this obscure) Vashti 07:41, 26 April 2006 (UTC)

The only word there I don't know is "Ruthe", which granted regular sound changes is very likely to be "Rod". In anycase, if it is a rod, "halbe" definitely means "half," so I'm going to amend the caption, but I still don't think that the picture is the best. JesseRafe 21:12, 26 April 2006 (UTC)

Having a common Germanic origin rod and Rute (Ruthe is the pre-1901 spelling) are in fact the same, in regards to language as well as measurement. (You could have found out yourself by looking at the German interwiki link.) It’s the same way for fathom and Faden for example. If someone found an English rod measure inscribed on some church or other building and photographed it, we might as well use that picture of course—just to show that this was done, especially close to market places. See mile for a less English-centric article on a measure, although it is by no means complete. Christoph Päper 13:21, 2 May 2006 (UTC)

I agree with JesseRafe that the picture shown is not a fitting example to accompany the description of what was the rod in the English speaking world for one very good reason. The Halb-Ruthe shown is a "half-rod" as used in Bavaria at the time stated. The word Ruthe is the old German spelling of Rute which is the German for a "Rod" (see Die Haupteinheiten in Bayern below). However, the Ruthe as used then in Bavaria was a duodecimal rod of 12 Bavarian feet. This can be verified in three different ways. First, the length stated for the Halb_Ruthe is 1.883 metres which is equivalent to 6.1778 Imperial feet. By no stretch of the imagination could this equate to a rod of 16.5 feet even taking into account the differences in Bavarian and Imperial feet. A second argument for a duodecimal rod is the fact that when one views the picture in expanded form, the Halb-Ruthe can be clearly seen as having six equal divisions and thus a complete Ruthe would have 12.

The web page at http://home.fonline.de/fo0126//geschichte/groessen/mas7.htm has the description description of the rod or "Ruthe" (which is quoted with that spelling) of "1 rhein. Fuß = 1,07536 bayer. Fuß = 0,31385 Meter [0,31374 m (seit 1816)]" which translated says 1 Rein foot = 1.07536 Bayern feet which = 0.31385 metres but [0.31374 metre since 1816]. It should be noted that the date on the the Prussian rod in the image is 1816!!! The very next line also says "1 Ruthe = 12 Fuß = 144 Zoll = 1728 Linien (also duodezimale Einteilung)" which in English is "1 Rod = 12 Feet = 144 inches = 1728 lines (also a duodecimal usage)". The image of the Halb Ruthe (half rod) can clearly be seen to have 6 equal subdivisions which acords with the description of the Ruthe having 12 Fuß. Now using the 1816 specification of the Prussian foot of 0.31374 metres, this gives a Ruthe of 12 x 0.31374 = 3.76488 metres or a half rod of 1.88244 metres which is close enough to the size quoted for the imaged rod.

I earlier suggested the picture should be removed as it has little relevance to the Imperial rod of 16.5 feet. However, I have changed my opinion but would suggest the addition of an image of the Imperial rod. This would serve to illustrate the different found from country to country and even province to province.Ruthe (talk) 22:33, 19 August 2009 (UTC) —Preceding unsigned comment added by Ruthe (talk • contribs) 01:18, 21 June 2009 (UTC)

Münster is not in Bavaria, it's in North Rhine-Westphalia. In 1816, the date shown on the plaque, Münster was in the Prussian province of Westphalia. Zyxwv99 (talk) 22:23, 24 November 2011 (UTC)

The Prussian rod (preußische Rute) since 1816 was 3.766242 m. The half-rod should be 1.883121 m. Zyxwv99 (talk) 16:48, 29 September 2012 (UTC)

A perch was not necessarily a rod

Seems the value of a perch varied from 18-24' in the 1300's, and even in 1820, was between 16.5 and 25'. See the talk page at perch (area). I feel it would serve better to move the perch length info to a unified perch page that encompasses both length and area definitions, reflecting at least 600 years of use, and perhaps even explaining how one got to include the other, with a link here to what the length aspect became settled as recently. Any thoughts from on high? If none, I'll go ahead and attempt to do so (stretching my noob Wiki-skills). Andy N. (talk) 17:47, 5 March 2008 (UTC)

Prussian rod length

• German units of measurement - which has half a dozen print sources cited
• http://www.kartenmeister.com/preview/html/measurements__coinage.html
• http://www.heimatverein-heven.de/alte-masse/hevener-und-herdeder-masse.htm
• http://freenet-homepage.de/helmut.ramm/hopa13f.htm
• http://www.deutsche-schutzgebiete.de/deutsches_mass_und_gewicht.htm

all agree with the value of 3.766m for the prussian rod / 1.883m for half of same. --Random832 (contribs) 16:04, 1 July 2008 (UTC)

Lugs

In Dorset when I was young a LUG was a square POLE. I know useage varies in different parts of the country. —Preceding unsigned comment added by 82.33.201.184 (talk) 10:03, 12 February 2009 (UTC)

Rod Length Speculation

Why is a rod between 15 and 24 feet? Why this length? It seems to me that it may have come, not from the length of an ox goad, but from the length of a PIKE, which falls in the same range. In Medieval Europe, the peasants were the foot warriors a lord brought to battle, and they carried pikes as the only effective weapon against armored, mounted knights. Only knights could own horses and swords, so the peasants were pikers. To be effective, pikes had to be the same length, hence, I speculate, the local pike/rod was standardized for each 'county' that is, the domain of a count or earl. I spent some time researching this speculation with the OED, and the closest definitional association is with the 'perch', which referred to poles as weapons. The spindly nature of the 'rod' as compared to the 'pole' or 'perch' suggests to me that a rod may have been a specific standard measure used by the bailiff to make standard pikes (one OED citation is for an order of 3000 pikes) and to lay out standard allods for the peasants (which is where we get house 'lots'). I have exhausted what I can do with the OED and have no intention of becoming a Medieval scholar. Matt Persson (talk) 01:38, 3 May 2010 (UTC)Matt Persson

Spelling and metrication

See a discussion under the same heading at WT:Manual of Style (dates and numbers). Jc3s5h (talk) 17:30, 9 June 2010 (UTC)

Overzealous nigglers

Someone blasted this entry with 's all over the place. I removed one entirely superfluous criticism - the request to cite a source for the sentence, "The rod was still in use as a common ... when Henry David Thoreau used it frequently" in Walden". I mean, c'mon people, did you even read the freakin' sentence? And if you don't understand what I'm saying, you're probably not qualified to add "citation needed" tags all over the place.

As a professional nitpicker, I take issue with what I perceive as anti-overzealous-niggler bias. I'm not sure how relevant the Thoreaux anecdote is, but I have supplied a reference for it. Zyxwv99 (talk) 18:42, 27 November 2011 (UTC)

History

I just deleted this:

The length is equal to the standardized length of the ox goad used for teams of eight oxen by medieval English ploughmen;

The source cited says "may have." Also, it is an online source that does not cite its own sources. I did some additional research a(searching Google Books on rod measure ox-goad and found that this story goes back at least to the 1890s, but not from any reliable source. More recent works qualify it with "may have."

Another concern is that the rod as a unit of measure appears to be of such great antiquity (Bronze Age? Neolithic?) that any story regarding its origin is suspect. Something like "fire was discovered in the 15th century by a Greek shepherd who accidentally rubbed two sticks together." Zyxwv99 (talk) 23:27, 24 November 2011 (UTC)

The following accompanying reference was removed from the Reference section:

Zyxwv99 (talk) 23:37, 24 November 2011 (UTC)

The starting paragraph is utter nonsense. In the 13th century, the English codified the definitions of acre, rod (perch length), perch (perch area) based on customary measures going back to Anglo-Saxon origins. The only new technology from the 17th century was the chain, equal to 10 rods. Just because James Burke says so, doesn't make it true. — Preceding unsigned comment added by 99.183.237.29 (talk) 20:42, 16 April 2014 (UTC)

I do not agree with the chain being 10 rods. Actually 10 chains equal one furlong. Four rods (5.5 yds x 4) are, of course, 22yds or the length of a cricket pitch, ie. one chain! — Preceding unsigned comment added by 79.64.40.67 (talk) 18:58, 14 June 2015 (UTC)

The North German foot?

A sentence here read "The early Anglo-Saxon rod was based on the North German foot of 335 mm." I think it was User:Zyxwv99 who first added it. I've removed the phrase "of 335 mm" as an anachronism - the North German foot, whatever it was, could not have been of 335 mm because the millimetre was not defined until half a millenium or so later. It looks as if this sentence is referenced to Zupko, a work that unfortunately I do not have. So could I ask what sources Zupko gives for this "North German foot", and what credence we should place on it? Because our own foot article has many German "feet" of many and various lengths from different times and different places, as is really to be expected in the history of any measurement, and (for me) assertions of some fixed value in mediaeval times set the alarm bells ringing - perhaps someone has been reading too much of the work of the good doctor Rottweiler? Justlettersandnumbers (talk) 00:58, 23 February 2012 (UTC)

My initial source was Zupko. Since then I've found a second source, R D Connor's Weights and Measures of England. However, I am beginning to suspect that both Zupko and Connor are unreliable for events prior to c. 1300, so would have no objection to that part being deleted. (It was actually on my to do list). As for the so-called North German foot, Connor says there were about 8 different feet in north-western Europe in classical antiquity that fell within the range of 330-335 mm, the most famous being the Drusian foot (named after Nero Claudius Drusus) who did not invent it, but merely noted it in his writings.

Defining ancient and midieval measures in terms of their modern equivalent is standard practice in academia.

As for fixed values over long periods of time, what you say seems to be quite true for nearly all units of measurement. However, the rod seems be one of the rare exceptions, as archaeologists seem to have found evidence for the rod as far back as Anglo-Saxon times.

Finally, who is doctor Rottweiler? Even though your comment on the whole was thoughtful and I agreed with nearly all of it, the snide remark at the end has set off alarm bells. Since I suffer from Asperger's syndrome, I can relate if you too suffer from a similar disorder, but I think it's important to try to keep it under control on the Wikipedia. Zyxwv99 (talk) 04:05, 23 February 2012 (UTC)

Hmm, Rottweiler was a slip of the brain, sorry. Rottländer was what I meant, the chap who writes stuff like this about the numerological relationships between totally unrelated units. I apologise. My intent was not to delete anything, but to discuss how this passage could be better worded and better referenced. I'm aware that you have looked carefully at a lot of sources. If Connor is a reliable source and mentions various feet in Germany in Roman times, perhaps we should consider adding those to the length section of Ancient Roman units of measurement, and to Foot (unit)? If there's some sort of academic consensus that the foot in northern Germany in Roman times was usually in the range 330-335 mm then let us by all means put that in this article. Even if Zupko's theory of how the rod came to have such a strange value is just that, Zupko's theory, I see no objection to mentioning it here if it is well-founded and if we make clear that it is just one of many possible explanations. On constancy of value, I personally find it truly remarkable that the value of the (Roman-British) foot should have remained so nearly the same for 2000 years, with a variation of only a few percent over that time; but I don't think that that relative constancy can be allowed to imply that any equivalence can be exactly determined. Hope this makes sense. Justlettersandnumbers (talk) 11:48, 23 February 2012 (UTC)

Thanks for the explanation. I see what you mean about Rottländer. He also references the infamous A. Thom. The Drusian foot is already mentioned in the foot article. Connor says it was introduced to Britain by the Tingri (a Celtic people) who arrived in Britain in 6 successive waves in the 2nd and 1st centuries BC. The Romans also (apparently) used the Drusian foot in the northern provinces. However, the evidence for any sort of foot between the Roman era and the Composition of Yards and Perches (c. 1266-1304) is so weak that a) it should be labeled as "just somebody's theory" and b) go under "foot", not here.

There does seem to be moderately strong archaeological evidence for a unit of 5.03 metres (or in some sources 5.029) going back to at least the 13th century, specifically urban building widths, although they seem to be whole numbers of half-rods as well. Also, some evidence for whole numbers of rods in the widths of Anglo-Saxon churches and cathedrals, with building lengths involving the same unit times the square root of two (i.e., the diagonal of a square), a ratio commonly found in Greek and Roman temples (not to be confused with the Golden Ratio, which involves phi). The long-term stability of the rod could plausibly be accounted for by its use in buildings and land measurement. Statistical analysis of the evidence for smaller units, e.g., feet or yards, using the same evidence, i.e., building dimensions, yields an unacceptable signal-to-noise ratio. Zyxwv99 (talk) 14:10, 23 February 2012 (UTC)

Perch = Rod?

The following discussion is closed. Please do not modify it. Subsequent comments should be made in a new section. A summary of the conclusions reached follows.

Merge Rood (Scots) and Perch (unit) into Rod (unit). Klbrain (talk) 15:46, 6 May 2016 (UTC)

---

Hmm, I've just added a table here with many kinds of perch, pole and rod from around Europe, and now realise that there is also an article at Perch (unit). I'm wondering whether there is any good reason to treat the perch separately from the rod, or if they should not be merged? And if so, under what title? Justlettersandnumbers (talk) 19:45, 23 February 2012 (UTC)

Rod and perch have been generally synonymous for about the last 700 - 750 years, which is about as far back as the history of English weights and measures can be traced with any degree of certainty. Etymologically, rod is Anglo-Saxon/Germanic while perch is Anglo-Norman French. At some point they may have been different, but at a time for which we have no historical evidence. English-language encyclopedias usually merge them into rod (perch, pole). There are, however, local and specialized variants where perch is used exclusively, mainly the woodland perch. Zyxwv99 (talk) 01:55, 24 February 2012 (UTC)

A rod is always a unit of length while a perch has multiple meanings. Also I think that citing others encyclopedias mergers of terms isn't necessarily valid grounds either. Darqcyde (talk) 14:59, 28 February 2012 (UTC)

A rod was also a unit of area. I've suggesting merging that short article, Rood (unit), and its even shorter Scots equivalent, Rood (Scots), here also, so that one topic can be dealt with in one place. Back in the late Paleolithic, when I was at school, we learnt that 5 1/2 yards equalled one "Perch, pole or rod". I tentatively suggest that as a suitable title for this article if the merger goes ahead. And yes, I agree with Zyx that on the face of it perch and rod appear to be two differently derived names for the same thing. Justlettersandnumbers (talk) 21:22, 29 February 2012 (UTC)w

If this is the merge discussion, then I would be opposed to a merger. If the Rod, Pole and Perch are the same length, that doesn't make them the same thing; they have different backgrounds and histories which are better explored on separate pages. It is enough to say that they became equivalent (at some point; it's far from clear here when). Moonraker12 (talk) 11:30, 13 April 2012 (UTC)

OPPOSED Rod, pole, and perch are used interchangeably (though in practice rod is most often used) in measuring the 16-1/2-foot *length*, but for area the use of "perch" is almost exclusive, probably stemming from the perch also historically representing units, if I recall correctly that defined both Scots and Irish miles and acres, whereas this didn't apply necessarily to pole, and rod, pretty certain the pole never referred to Irish and Scots units.Surveyor792 (talk) 22:45, 28 September 2013 (UTC)

Support All the evidence that I have seen relating to units of measure suggest that the most significant difference between the rod, pole and perch was the original language, not the actual origin on the unit of measure - I see no reason why the rod, pole and perch should be any different to to foot, voet, Fuss, pied or to the pound! liver, pound! pond - the same word in different European languages for the same thing. I would also not put too much emphasis on multiple uses of the word "perch" - I have often heard British builders talking about "a metre of shingle" when they mean a "cubic metre". I cannot dismiss the suggestion that the same has happened with the perch. Martinvl (talk) 09:07, 29 September 2013 (UTC)

I've commented on the merge proposal (above) but I'd like to take issue here with the article content on this. It says:-

• "The Ancient Roman units of measurement of length included a rod or pertica...": well, does it? or does it just mention the pertica, and the rod has been added retrospectively?
• "In England, the rod is first defined in law by the Composition of Yards and Perches...": again, does it? The linked article quotes the statute, but only mentions perches. (I've also raised the matter on the talk page there)

So, do we have any information that refers specifically to the rod, or are we just conflating the two terms because they are now synonymous? Moonraker12 (talk) 11:52, 13 April 2012 (UTC)

Good question. From my reading of Zupko (British Weights and Measures) and Connor (English Weights and Measures) I vaguely remember rod and perch being synonyms from the beginning. Rod was an Anglo-Saxon word, pertica the Latin equivalent, perch a later Latin form. However, my own vague memory is not enough to withstand a challenge, so I concede defeat until such time as I can produce reliable evidence to the contrary. Until then, feel free to make whatever edits you feel are warranted. Zyxwv99 (talk) 13:03, 13 April 2012 (UTC)

I have recently acquired a copy of Ther Basis of Measurement McGreevy - 1995. McGreevy states quite unequivovably that teh pole, perch and rood are one and the same thing. Martinvl (talk) 06:57, 11 September 2012 (UTC)

The discussion above is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.

Dubious

I marked the table as dubious. The issues:

• The "Local name" column does not exist in the reference and is obviously wrong - for example, it states the German Ruthe as the local name for the unit in e.g. Amsterdam and Sweden. Almost needless to say, that isn't the name given in the respective language Wikipedias: roede and stång for the Dutch and Swedish versions of the page, respectively.
• The "Local equivalent" column is likewise in German units (Fuß).
• The "Metric equivalent" has different equivalents for the same number of Fuß and, again, checking the other language versions gives a wildly different conversion: 2.969 m compared to the table's 4.748 m for the Swedish rod, for example.

Kolbasz (talk) 13:49, 10 April 2012 (UTC)

Plenty of these sorts of tables can be found in Google Books by filtering for 19th century (or in books from antiquarian bookstores). The problem seems to be that these lists are not merely based on 2nd or 3rd generation copies of older lists, but more like 10th or 20th generation, with 1% to 2% error rate at each generation. My preference would be to put such lists (or links to the sources) on the talk page, but not include any item in the article until it has been fact checked. Zyxwv99 (talk) 01:48, 11 April 2012 (UTC)

I'm not sure about it, either. I've made it sortable, for ease of comparison, but they still seem all over the place. And if the values given by the source are different to the units mentioned I'd question the source's reliability. Also, I don't think we should be measuring in "fubs" here, either.

What happened to the paragraph that was here saying the Anglo-Saxon Rod was derived from the North German foot? That, at least, made sense. But there's nothing to say why the Rod is the same as the other measures listed (or even a source to say that it is). It'd be more useful to explain (or link to) the other European measures and let people decide for themselves how equivalent they are. Moonraker12 (talk) 11:20, 13 April 2012 (UTC)

The Tudors ensured consistency of weights and measures in England, Ireland and Wales. When Scotland joined the Union in 1707 they were required to adopt English measures. When the Americans declared their independence, they inherited English measures. In the mid-19th century, the Americans and the Brits tried to coordinate their units of measure - they failed miserably with the gallon, but kept the pound and the yard sufficiently close that for purposes of trade they were interchangable. In Germany things were very different. Each community had its own prince, grand-duke, bishop, king of city council. Each managed their own weights and measures.

Maybe this article is being approached from an Anglo-Saxon mindset, not a universal mindset. I am quite happy that the source given is approximately correct - possibly we should get another two or three sources and cross-reference them. I am also happy that local measurement should be given - after all the US gallon has 16 fluid ounces and the Imperial pint has 20 fluid ounces. I trust that fact is recorded in the article on the gallon. Martinvl (talk) 13:21, 7 August 2013 (UTC)

I have removed the "dubious" tag and made provision for other references to be added. Martinvl (talk) 13:21, 7 August 2013 (UTC)

I'm readding the tag, as the table as is is presented as factual. Attributed misinformation is still misinformation. Kolbasz (talk) 19:07, 17 November 2013 (UTC)

metre v meter issue

Special:Contributions/91.85.61.106 recently changed "meter" to "metre" in this article. Even though someone changed it back and left a tag on the user page, this seems to be an ongoing problem. This users entire edit history consists in changing American English to British English. This user also appears to be a sock-puppet of Special:Contributions/82.153.125.210, suggesting the possibility that this may go back even further. I hesitate to use the term cyber-terrorism, but this could be part of a coordinated attack on the Wikipedia. Then again, maybe I'm just overreacting Zyxwv99 (talk) 01:53, 29 September 2012 (UTC)

You are not over-reacting. When I see somebody changing "metre" to "meter" or vice-versa, I usually revert (unless the change is justified). I don't see the point in having UK/US English battles and I certainly do not object to people changing my UK English to US English if I inadvertently use UK English in an artcile that is already designated as using US English. Martinvl (talk) 21:58, 28 January 2013 (UTC)

Always a point of contention this one. Surely the easiest solution is to have 'meter' where the article is of predominantely USA origin or relevance and 'metre' where the article is more applicable to non-USA interests. This allows for familiarity for the reader of their own education system. I might change one to the other, if I were adding information to a page and wanted to apply a uniform spelling to the whole article but surely having different spellings accentuates the whole idea of Wikipaedia (couldn't resist) being a collection of knowledge from around the world? — Preceding unsigned comment added by Ragebe (talk • contribs) 08:17, 8 July 2014 (UTC)

Ragebe's suggestion agrees with the guideline MOS:ENGVAR. Jc3s5h (talk) 14:27, 8 July 2014 (UTC)

Chanvar bhiga

Chanvar bhiga = 3025 square yards or 100 square rods. --Pawyilee (talk) 15:45, 31 December 2012 (UTC)

Sentence questioned

"A rod is the same length as a perch also sometimes called a pole which measure using cordage[3] or wood, slightly antedated the use of both rods and surveyors chains, made of more dimensionally regular materials" - Does this sentence make sense? I can't make head nor tails of it. Mazz0 (talk) 00:55, 25 June 2014 (UTC)

Y'know... if it's more commonly known as a rod or a perch, why is the article title pole?

I was wondering the same thing. And that characterization is absolutely correct, not a misstatement of fact in this article. Gene Nygaard 21:00, 28 Jan 2005 (UTC)

Rod as a volume

A recent edit asserts that as a volume, 1 rod = 1000 cubic feet. I doubt the reliability of the source. Please see WT:WikiProject Measurement#Rod as a volume where I'm asking for comments. Johnuniq (talk) 10:12, 18 December 2014 (UTC)

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Dubious volume claim

I removed this sentence:

• As a unit of volume, a Rod equals to 1000 cubic feet.

This seems highly unlikely; the brickwork measure is clearly genuine (I cross-checked, and it's in SOED for example). This claim, apparently unrelated to the standard rod/pole/perch length of 5-1/2 yards, is supported only by the Cardarelli book, which is dubious (there is at least one other misprint in the table from which this is drawn, the notorious "stupping ton" (misprint for "shipping"). I cannot put "citation needed", because Cardarelli is a citation, but he does not give any sources, so this is unlikely to be more reliable than "stupping ton". Imaginatorium (talk) 15:35, 23 July 2018 (UTC)

References

Thanks. I mentioned the problematic edit in December 2014 here. Johnuniq (talk) 22:25, 23 July 2018 (UTC)

Exact and approximate values

@Jc3s5h: and @Johnuniq: you have reverted recent suggestions that the value 5.0292 meters for the rod is exact.

Do you agree to the two statements:

1. The feet is defined as exactly 0.3048 meters.

2. Multiplying 16.5 by 0.3048 gives 5.0292.

If you agree to the statements above, this article is logically inconsistent. Either both the feet and meter value are exact, or they are both approximate, but as currently written, the article doesn't make sense. -- Ws1920 (talk) 21:32, 2 March 2020 (UTC)

I'll start by adding emphasis to the first sentence in this thread:

@Jc3s5h: and @Johnuniq: you have reverted recent suggestions that the value 5.0292 meters for the rod is exact.

Various historical definitions of the rod exist, and to be strictly correct, the definition in effect at the time an old document was written should be used to interpret it. But, right now, the only country I know of that officially recognizes the rod for work performed today, March 2, 2020, is the United States. The National Institute of Standards and Technology (NIST) and the National Geodedic Survey (NGS) are working to finally eliminate the survey foot. NIST has a relevant announcement. According to the announcement, the change does not occur until "after December 31, 2022".

In the announcement NIST also makes reference to NIST Special Publication 811 (PDF version). That publication, published 2008, on pages 54 and 63, only gives approximate metric conversions for the rod, and indicates it is based on the US survey foot.

I found two NGS web pages on the topic, Fate of the U.S. Survey Foot after 2022: A Conversation with NGS and NGS and NIST to Retire U.S. Survey Foot after 2022.

Some of the states have passed laws which spell out the definition of various units or coordinate systems, rather than just referring to the latest NIST and NGS publications. It's possible some of these states may revise their legislation, so the full answer won't be known until enough time passes to presume that the states willing to change their legislation have done so. Jc3s5h (talk) 22:53, 2 March 2020 (UTC)

Hmm, I hadn't realized the issue was that the conversion happens to give exactly 5.0292 meters. Of course "rod" is being used for the English rod whereas the Irish rod was 7 yards and no doubt others existed. Regardless of how countries currently define rod (if they do), it makes sense for the lead to start with 5+1⁄2 yards for what a rod is. I'm not sure how to handle 5.0292 because it's just a fluke that it is exact. The solution is some tweak to the wording, perhaps to omit "approximately". Johnuniq (talk) 00:17, 3 March 2020 (UTC)

@Johnuniq:, I'll provide a counterexample to your statement that a rod is exactly 5.0292 m. The State of Vermont in the United States defines the default width of a road as 3 rods. This is not just for old records; if a new road were laid out today and the town did not otherwise specify the width, the width would be 3 rods. Vermont uses the US survey foot, so the defined width of the road would be 16.5 * 1200⁄3937 = 19,800/3937 ≈ 5.029210058420117 m. Can you provide a law from any jurisdiction that defines, for new measurements, a rod of exactly 5.0292 m? Jc3s5h (talk) 03:08, 3 March 2020 (UTC)

Of course it's not defined as 5.0292 m which is why I made my revert. The question is not what law applies but what text should go in the lead of the article. I guess you are saying it should be as it is now, with "approximately 5.0292 meters" which would cover most places. Johnuniq (talk) 03:50, 3 March 2020 (UTC)

I think the text should remain "and is approximately 5.0292 meters" because that value is accurate, to four decimal places, for any reasonable, current, definition of rod. Also, due to the position of the phrase in the lead and it's proximity to exact values, it is apt to be interpreted as an exact value unless stated to be approximate. Jc3s5h (talk) 12:04, 3 March 2020 (UTC)

Thanks for your comments. So it is actually not the common definition (1959 International) of the feet the intro is referring to. Shouldn't that be obvious to the reader? What do you say about this intro (replacing first sentence)? The rod or perch or pole (sometimes also lug) is a surveyor's tool and unit of length of various historical definitions, often between 3 and 8 meters. In the modern US customary units definition, it is exactly equal to ​16 1⁄2 US survey foot, ​1⁄320 of a surveyor's mile, or one-fourth of a surveyor's chain, and is approximately 5.0292 meters. --Ws1920 (talk) 15:51, 3 March 2020 (UTC)

NIST Special Publication 811 is written as if a present-day rod is exactly 16.5 US survey feet. But some states have adopted the international foot for surveys conducted in those states. So it isn't clear how the rod would be defined in those states.

In practical terms, rods are only used for relatively short distances, where the difference in the two definitions would be undetectable with normal surveying instruments. This is different from feet, which are used to express coordinates where the origin may be a hundred miles away, and the difference would be easily detectable. Jc3s5h (talk) 17:44, 3 March 2020 (UTC)

@Jc3s5h: as you mentioned, the statement by NIST is of high interest for the discussion above, and a potential coming reference in the article. Guess that answers the exact vs approximate question, but we are currently in the transition phase between current definition and new, harmonized definition. Now we just need to align when and how to update the article and introduction. -- Ws1920 (talk) 20:42, 3 March 2020 (UTC)

German units in Sweden and Denmark ?

In the list of Rods and comparable units in Europe, why are Sweden and Denmark represented by German units ? Flight714 (talk) 23:17, 5 September 2020 (UTC)