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WikiProject Plants (Rated C-class, Top-importance)
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American English was introduced to this article 23:09, 23 January 2005, with hyphenless "nonliving"‎. Sminthopsis84 (talk) 12:12, 28 May 2013 (UTC)

Merger of Vessel element[edit]

With regards to the proposed merger of vessel element into xylem:

  • oppose - since only the xylem of angiosperms contains vessel elements. My reasoning is thus (1) the two words are not synonyms, (2) vessel elements a specialized and taxonomically/evolutionarily significant specialization not found in most clades, (3) the structure, diversity, and evolutionary significance of vessel elements warrants an entire article in its own right. --EncycloPetey 02:38, 6 January 2006 (UTC)
  • oppose - per above; also, you'd have to merge in other things (tracheids, perhaps?) in order for this merge to be fair. it's 1) too much work and b) would bake xylem too big. -- Jjjsixsix (talk)/(contribs) @ 05:05, 19 January 2006 (UTC)
  • support- the xylem is a tissue that contains the xylem vessels in many plants and should be reflected in the article. I also think that tracheids should be included as again it is part of the tissue and is used instead of xylem vessels in many plants. I do not think that the risk of making the article is a valid reason for not including these elements as people who only require a very basicunderstanding can stop reading after the summary paragraph at the start or continue reading if they become intrested - —Preceding unsigned comment added by AdamClarke (talkcontribs)

(talk) 19 january 11:23 GMT

  • oppose: "vessel element" appears to be in order, while "xylem" remains not only an accident waiting to happen, but an accident in progress. Not all xylem contains vessel elements. Xylem (secondary xylem that is) may contain many kind of cell types except vessel elements . Brya 18:44, 19 January 2006 (UTC)
Qualifying this: merging can be made to work, but this still would need illustrations and quite a bit of careful work. At the moment the differences between primary and secondary xylem are snowed under. I would be a lot happier about merging if indeed separate (if short) entries for secondary xylem, tracheid and vessel element could be maintained. If it were possible to make redirects to wiktionary the shortened versions of "tracheid" and "vessel element" could be moved to become wiktionary entries. Starting with a summary would be a good idea also.
All in all, if "xylem" is to be expanded I would prefer to see the various aspects built up as separate items, before considering merging. Brya 08:35, 27 January 2006 (UTC)
  • support: Since I have contributed to this article I suppose I should weigh in to say that I support putting information on vessel elements here, rather than in an article of their own. Either redirect or give "vessel" or "vessel element(s)" minimal definitions with a link to this article. It just makes sense to discuss all the elements of xylem together, even if they don't always occur together at the same time in the same plant. (And yes, I suppose that implies merging "secondary xylem" into this article sooner or later also...) MrDarwin 22:02, 25 January 2006 (UTC)
  • support: It seems to me that vessel elements - and indeed tracheids - are the defining features of xylem, and the details of their function, their similarities and their differences are best described in a single article. Obviously it is important that basic definitions of vessel elements and tracheids exist under their own headings, but as these articles currently stand, moving the bulk of each of them into "xylem" would allow a more consistent and cohesive treatment. "Vessel element" would need to be a much larger article to warrant independence. Lycanthrope 20:49, 26 January 2006 (UTC)
    This is incorrect. Most clades of xylem-bearing plants lack vessel elements. The defining feature of xylem in recent cladistic and morphological literature seems to be the presence of the compound lignin, not a cell type. In fact, some of the "xylem" in the Silurian rhyniophytes has been found not to be true xylem, despite the structure of the cells. See the research of Paul Kenrick for details. --EncycloPetey 18:44, 15 May 2006 (UTC)
  • comment Barring the above indented bit, it seems like no discussion has been going on for several months but the merge tags are still there? Personally I have no preference over merging or not, but if you do merge, perhaps organize xylem into sections with a Main article: .... I still don't understand the difference between tracheids and xylem elements, at least my textbook gives the exact same descriptions of both, so please make these distinctions clearer thanks. 14:32, 19 June 2006 (UTC)
    Tracheids are one of the kinds of cells found in xylem; there are many others that may be found in xylem. --EncycloPetey 05:33, 28 November 2006 (UTC)
  • oppose This is a very important part of a plant, along with the phloem. That is a seperate article and this should be too. Superbowlbound 19:07, 26 November 2006 (UTC)

Merge of Tracheid into xylem[edit]

Oppose I do not believe that every information need to stay only in giantic compilations of it's superordinate topic.
Tracheid is not the synonymum of xylem nor such merging would help to understand the topic of tracheids, tracheids formation, it's contribution to plant developement, the role of auxin to plant organ selforganisation. Nor inclusion of all that stuff in the xylem would help the xylem article, as not all those actions are relevant to xylem etc. Simply let each information unit have it's own article. We can simply borow some descriptive sentences from one article to the second one. It does'nt harm anything. Reo ON | +++ 23:03, 28 September 2006 (UTC)

oppose. whats up retard nation —Preceding unsigned comment added by (talk) 17:11, 18 November 2010 (UTC)


Well, obviously I am glad to see people taking an interest, and even more glad to see some movement in this incomprehensible deadlock. However, this insertion of a discussion on vessel elements means that in effect the merge is going through, here and now. To me it looks as if clarity would be served by moving everything on vessel elements into either vessel element or into a evolution related topic (like the big vascular system entry that was hinted at. Brya 21:54, 25 January 2006 (UTC)

Oppose on the basis that the xylem article is still too unstable to merge anything into it. In cases of incomprehensible deadlocks we must go with the no concensus - no merge plan, clear the tags, and allow progress to resume. Meggar 18:27, 14 September 2006 (UTC)

Xylem function[edit]

For the simpler folk amongst us, could you put in a statement (if it is true) that "in trees, all the inside wood of the tree is xylem. In other words, soil water with nutrients is transported by the entire stem of the tree, exclusive of the outer layer which transports sugars from the leaves around the tree to where it is needed." This is implied by the article but is it indeed so? —Preceding unsigned comment added by (talk) 05:59, 9 January 2008 (UTC)

No, it is not so. The central wood (heartwood) in a tree usually is dead and no longer functional. In tropical trees, the center may even rot away, leaving the tree as a hollow cylinder. Only the living xylem continues to transport. --EncycloPetey (talk) 01:29, 11 January 2008 (UTC)
In addition, not all the sapwood conducts water; in many temperate oaks, only the last year of xylem conducts water, all the previous years' vessels being blocked by air embolisms.--Curtis Clark (talk) 05:46, 11 January 2008 (UTC)

Massive (?) merge[edit]

(from User talk:Ettrig)

This isn't the title I gave to the section when I created it... Peter coxhead (talk) 08:36, 23 March 2011 (UTC)

I notice that you have been adding/moving material re evolution into Xylem. I think it would be useful if you could (a) explain the overall idea behind your work, perhaps at Wikipedia_talk:WikiProject_Plants (b) seek some consensus for it. Personally, I think that it just swamps articles like Xylem to have such a large section on its evolution. Someone who wants to know what xylem is, what the word means, doesn't want such a large article. What are the arguments for and against a separate article on the evolution of xylem? Peter coxhead (talk) 15:38, 21 March 2011 (UTC)

You assume that a person who looks up xylem in Wikipedia only wants to know what xylem is, what the word means. I hold it is extremely unlikely that this holds for all readers. And even if it did, it would be against the general principles of Wikipedia to follow up this thought in action. I don't like the strict separation, but Wikipedia is about the world and Wiktionary is about the words and their meanings. This holds also for xylem. We should split up the information about xylem when the article is too long. To see what the optimum length is we can take a hint from the average length of featured articles. Xylem has long to go before reaching this standard. --Ettrig (talk) 16:44, 21 March 2011 (UTC)
Actually I don't assume that everyone who looks up xylem only wants to know this, although I would point out that xylem is cross-referenced from many plant articles which need to use the term in describing plants, so there could be many readers who just want morphological/anatomical information – this requires much more than a Wiktionary entry. I'm not sure that you can rely on the length of featured articles per se; coherence is a more important issue. One test I would apply is how other editors are likely to want to wikilink; if wikilinks start becoming to sections that might suggest splitting, regardless of length. Just as an example, Xylem development is currently separate from Xylem. Is this a good idea or not? I tend to think it is, because in developing articles on early land plants, I regularly want to link to some aspect of xylem development, rather than the whole topic of xylem. But it's debatable – so to merge them would require a debate.
I can only repeat that I think it would be helpful to everyone if explained how you think evolutionary issues should be dealt with in plant articles and discovered whether there is a consensus behind this approach. Peter coxhead (talk) 17:26, 21 March 2011 (UTC)
You would rather follow your own views than taking the example from the articles that the community has spent much effort on identifying as the best. You think that xylem isn't worthy of a full length article. You have many personal views. I am probably not as interested in them as you are. In the swedish community I would have called this rått kött (raw meat). A not well adwised person created a lot of articles by adding a qualification to a noun. It took some effort by the community to make him (?) stop. Xylem development is a lot like raw meat. One aspect broken out arbitrarily. I find your motivation very constructed and (again) personal. --Ettrig (talk) 17:39, 21 March 2011 (UTC)
Imagine that the article was nominated for Good Article. The complaints would not be that the merged material does not belong here, neither would it be that the article is too long. This is a statement that can be tested. --Ettrig (talk) 20:09, 21 March 2011 (UTC)
All I asked, and I think it is quite reasonable, is that you don't make major changes to articles without seeking consensus, either on the talk page for the article, or on the Wikipedia_talk:WikiProject_Plants page. I did not say that I wanted you or anyone else to follow my own views, only that there should be discussion first. In the specific case of Xylem development, I actually merged separate articles on centrarch, endarch, etc. I have no general preference for lots of separate articles, nor for single large articles. I think there should be a case-by-case discussion and an attempt to reach consensus. Now you have merged two articles without any discussion. This is not helpful.
The redirections for Centrarch, Endarch, etc. are now wrong. They should not be to the whole article but to the section on xylem development. Peter coxhead (talk) 10:44, 22 March 2011 (UTC)
I support the merge of Xylem development into Xylem–it strikes me as material which is more naturally discussed along with other aspects like primary versus secondary and so on. The evolutionary material might be slightly more easily split out, but I'd probably keep it here for the moment (and make the decision largely on size, per Wikipedia:Splitting). As for discussion, there is no requirement to discuss merges, but on the other hand, there is no rule against reverting merges either (see Help:Merging), so this isn't an especially strong argument one way or the other. With respect to statements like "I find your motivation very constructed" and so on, I would ask you, Ettrig, to WP:AGF. I've had plenty of civil conversations with Peter coxhead on many plant-related articles and in a case like this there is no need to attack motives instead of discussing the pros and cons of merged versus separate articles. If the two of you can't agree, get a third opinion from WT:PLANTS or Wikipedia:Third opinion. And I'd also ask you, Peter coxhead, to realize that Ettrig is improving the encyclopedia (the evolutionary material looks nice, although I didn't spend too much time reading it, and which article it should live in is a detail rather than a big deal). Kingdon (talk) 01:33, 23 March 2011 (UTC)
I don't think that reversion would be a helpful move here, although I know that it is within WP policies. I also know that Ettrig doesn't have to discuss merges first, although it seems to me that most people working in the plants area do (see the discussion above re merging "vessel element" into "xylem"). Notification/discussion is useful not only because there may not be a consensus for a merge, and thus unhelpful reversions can be avoided, but also because other editors often know of links to the original articles and why they are there and hence where they can best be re-directed. Merging "Xylem development" into a section of "Xylem" without checking individual links leaves some in an unhelpful state to readers, e.g. Exarch is usually best not linked to the entire article on xylem.
Given that Xylem is now a large comprehensive article, there are others that should be looked at, e.g. is there now a point in keeping Tracheid separate? Vessel element is a little different because it covers more than xylem.
Everyone's time and effort could be saved, in my view, if there is prior discussion. Peter coxhead (talk) 08:00, 23 March 2011 (UTC)
Xylem is an article of high importance in project Plants. With a low effort I made it comprehensive (cited from previous comment). In my view this is a very good change. I consider the negative side-effects mentioned in this discussion to be minor in comparison. --Ettrig (talk) 08:15, 23 March 2011 (UTC)

Ok, well the merge has been made. Some comments:

  • I would now merge Tracheids. This would make it more comprehensive.
  • The evolution section needs a bit more work. The discussion re early plants is not quite up to date with the latest ideas on the evolution of water conducting vessels. If you are going to discuss the evolution of tracheids, then S-type, G-type, P-type, etc. need describing and discussing. I was going to do this somewhere later on, because it's really needed in describing early land plants.
  • The effects of changing levels of CO2 are not universally accepted; the article could do with some balance from other views.

I'll only have intermittent online access for a while, so I can't look at this myself at present, but will later if no-one else does. Peter coxhead (talk) 08:36, 23 March 2011 (UTC)

Primary Xylem vs. Metaxylem[edit]

In the section "Primary and secondary xylem" it says "Metaxylem has wider vessels and tracheids than primary xylem.". This should probably be edited to "Metaxylem has wider vessels and tracheids than secondary xylem.", as Metaxylem is part of the primary Xylem and the vessels of sec. Xylem are generally wider.

Can s.o. please confirm and maybe edit this? — Preceding unsigned comment added by (talk) 20:04, 15 November 2012 (UTC)

Good catch, but I think it means "than protoxylem". Depending on the plant, the metaxylem vessel elements can be wider or narrower than secondary xylem elements.--Curtis Clark (talk) 20:39, 15 November 2012 (UTC)

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