Sunday, August 28, 2016

Bad taxonomy can kill world records


Or, When the world's tallest dandelion isn't a dandelion. 
The motto of The Guinness World Records is OFFICIALLY AMAZING.  And that it is, officially amazing, but not only in the sense that they might think.  When I was a kid in Sweden I loved their orange-colored book, (1975 edition, maybe?) and I read everything in it, and stared at the photos of the man with the longest nails (how did he eat?) and the largest cat, amused and entertained and informed.  Now I get to come back to this memorable source of trivia, but this time for a botanical and work-related reason.

The world record for the tallest dandelion is nearly a foot taller than most people was found by two Canadians 2011.  They had their dandelion verified by two experts in Canada (see below) and accepted by the Guinness office as an official world record. From the Guinness website:
"The tallest dandelion measured 177.8 cm (70 in) and was found by Jo Riding and Joey Fusco (both Canada) in Ontario, Canada. The dandelion was measured on 12 September 2011. The dandelion was found on 4 August 2011 and was unofficially measured at 76 in. The dandelion was then officially measured by NutriLawn and The Weed Man on 12 September 2011 when it had dried out and was measured as 70 in."  (link)
There is no photo of the plant on the record website, unfortunately, but there is a youtube video uploaded by JO Riding, telling the whole story of finding and measuring of the plant. 

By the time the plant was measured it had been dried for weeks, but you can clearly see in the video that it had many leaves on its stem, and that there were several flowers on the top of several branches.  There is no clear taproot and no rosette of basal leaves. To conclude, this was no dandelion. (And just to confirm, the Canadian botanist Luc Brouillet who wrote the Flora of North America treatment for dandelions, agrees with this conclusion.  And he should know.)

There are many species related to dandelions (genus Taraxacum) that are similar to dandelions in having yellow flower heads and 'puffball' seed heads that eventually blow in the wind, but they are not dandelions, they below to other genera.  All of these are members of the sunflower family (scientific name Asteraceae), and dandelion and its relatives are members of the Cichorieae (aka Lactuceae) subgroup (=tribe) that has members with milky sap (latex) that you can see if you break a leaf or stem.
Dandelion (Taraxacum)  from Lindman's Bilder ur Nordens flora, Public Domain.
Here is a real dandelion, a species in the genus Taraxacum. All the leaves are in a basal rosette at the base, and from the middle of the rosette a light-colored, hollow stem comes up and holds just one flower head. There is a big taproot under the plant that can survive year to year, and that is why they are so hard to get rid of - you have to dig them out. It is a perennial problem - cut the flower head stalk off with your lawn mower and it just sends up a new one from its low stem and perennial root.
Milk Thistle (Sonchus arvensis), illustration from
Otto Wilhelm Thomé Flora von Deutschland, Österreich und der Schweiz (1885), Public Domain.
And here is a weedy look-alike, but check out the differences in the position of the leaves and the branched stems with many flowers.  This is a milk thistle (Sonchus), which is probably what was reported from Ottawa as the world's tallest dandelion. It is unclear if the two Ottawa companies that certified its height, Nutri-Lawn and Weed Man, also certified its species identity, but both companies should be very familiar with dandelions and other weedy species.  Nutri-Lawn is a lawn care company specializing in "ecology friendly lawn care" and Weed Man, another gardening company has a very funny green man as their home page mascot.  It might be that Guinness World Records didn't ask for species verification. 

And then there was this UK news story this summer, Man accidentally grows the 'world's tallest dandelion plant'
Screenshot from The Telegraph (UK) website (link) by BotanicalAccuracy.com, 18 Aug 2016. Fair use.
" Mr Daniels is keen to get his dandelion officially measured as soon as possible before it starts to wilt or dry out. He added: "I'm not a gardener hence why I'm growing a dandelion, it is just luck that it has grown so big as I have done nothing to it over then let it grow." A Guinness World Records spokesman said: "We invite the claimant to make an application via our website in order for us to be able to ratify the achievement."
This is not a dandelion either. All those little flower heads in a strongly branched inflorescence and the leafy stems with bluish-green leaves with light-colored mid veins indicate that this seems to be Lactuca, maybe prickly lettuce (Lactuca serriola). Lactuca is the same genus as your supermarket lettuce, but this is a wild species. This is how Lactuca looks like. Some species have blue petals, other yellow.
Wild lettuce or prickly lettuce  (Lactuca serriola) from Köhler's Medizinal-Pflanzen, Public Domain.
For the record, WeedZilla with a height of 12 feet isn't the World's tallest dandelion either, that is something else in the sunflower family. It is a giant weed indeed, but not a dandelion. Sorry.   

The strange thing is that dandelions are not hard to identify with certainty if you know what to look for.  The book Foraging & Feasting: A Field Guide and Wild Food Cookbook by Dina Falconi includes a great 'plant map' illustrated by Wendy Hollender of all the good key characters for dandelions. You can also read about dandelion's great benefits and ancient ethnobotanical uses.  

I am not writing this to point out that people identify plants wrong.  That happens all the time, and is just a matter of education, curiosity, and interest in plants that live around us.  There are plant identification forums online with over 50 000 members, and the fact that people are curious about strange, cool, and giant plants is a great thing.  People should ask about plants, and let themselves be amazed by them. It is OK to know little, especially if you want to know more and satisfy your curiosity.

The problem is the fact checkers at Guinness World Records who put themselves and their company into this embarrassing situation.  First, they should make sure they actually have the right species in hand. The easiest for this is to have photos of the plant while alive, you know 'pics or it didn't happen!'.  They should also require a pressed specimen of the plant, not just air dried, but pressed between newspaper sheets so it is preserved and flat.  That way specialists can look at it later and say: "yep, you have a true dandelion!", or "sorry, that is a milk thistle, nice plant anyway!"  This is called vouchering and is standard practice for all species reports, including DNA testing, species inventories, herbal plant identification, and chemical analysis.  There is no reason why Guinness World Records could not implement this, and have a botanist verify the species identification and have a link to an actual preserved specimen (the proof). 

So, what is truly the record for world's tallest dandelion? Well, there are reports out there that show real dandelion (Taraxacum species). So far, the record seems to be the dandelion found by a Norwegian boy, Bjørn Magne, with a 108 cm (42 inches) long flower stalk, and reported to World Record Academy in 2007.  Before then, the Guinness World Book of Records had a 39-inch tall Swedish dandelion from 2003 as a record holder. The Nordic countries seem to be great for further giant dandelion exploration.  To inspire you, here are some dandelions on Iceland's lava-covered plains in the never-setting sun of Nordic summers. 
Dandelions on Iceland. Photo and copyright by Didrik Vanhoenacker (thanks for letting me borrow the photo).
PS.  Thanks to Asteraceae specialist Torbjörn Tyler, field biologist-on-call Didrik Vanhoenacker, professor emeritus Arthur Tucker, and dandelion taxonomist Luc Brouillet, who all helped and gave feedback on research for this blog post.

Thursday, August 18, 2016

Lichen or Moss - that is the hard question... also for science editors

It appears that New Scientist needs to rename their recent story " Without oxygen from ancient moss you wouldn’t be alive today" to something more like "Without oxygen from lichens you wouldn’t be alive today", based on their featured image. The story was posted on their website on a few days ago, and features new research findings of how the earliest land plants (bryophytes/mosses) helped put oxygen in the atmosphere; here is the webpage: 
Screenshot from New Scientist website (link) by BotanicalAccuracy.com, 18 Aug 2016. Fair use.
The story is based on a very interesting paper in PNAS by Timothy Lenton and colleagues at Exeter University.  A science writer probably wrote up the text, but along came a photo editor, who went to a stockphoto gallery, in this case Getty images, to find a suitable image.  And he/she selected a lichen, not a moss, since that 'moss' is what the photographer had written in the description. Nobody appears to have checked with the authors of the paper or any other botanists if the image was suitable or correct.  (My advice for scientists is to always provide your own images for news stories, for exactly this reason.)
Screenshot from Getty Images by BotanicalAccuracy.com on 18 August 2016 of 
'Close-Up of Moss on Rocks' photo (link), featuring a lichen, not a moss. Fair use.
The bushy, light-colored lichens of the genus Cladonia shown above (also known as reindeer lichens and many other names) are seemingly perpetually misidentified and mislabeled as mosses, I have written about this elsewhere here on the blog.
White lichens, green mosses, and Swedish Christmas...
Reindeer moss is a lichen, not a moss

So how to avoid mistakes like this? It would be very helpful if stock photo companies demanded accurate descriptions of photos, and if media checked the images with the people that know, not the least the authors of the paper that is featured.  I can just imagine their frustration and possible horror to have their bryophyte story illustrated with a photo of a lichen, especially since there are so many gorgeous moss photos.  

PS.  Thanks to TT who notified me of this mistake, which hopefully will be corrected by the New Scientist editors very soon.
PS2. UPDATE: The photo is now corrected in the article in New Scientist. 

Saturday, January 9, 2016

Fine cooking out in the cabbage patch

In the most recent issue of the fine cooking magazine Fine Cooking, the writers have gone out on a somewhat thin taxonomic limb.
The Brassicas article in Fine Cooking.  Photo by BotanicalAccuracy.com.
So, what do they write?
"Arugula and turnips bear little resemblance to one another on the plate, so you might be surprised to learn that they both belong to the cabbage family, otherwise known as Brassica."
Well, arugula and turnips are both member of the cabbage family, but that family is called Brassicaceae, the mustard or cabbage family. Even if turnips is placed in Brassica, arugula is not, and in fact, the two commonly cultivated species of arugula are in different genera.

The article continues:
"Other members include broccoli, Broccolini, broccoli raab, Brussels sprouts, cauliflower, cabbage, collard greens, mizuna, tatsoi, kale, watercress, radish, and horseradish." 
Yes, these are all members of the mustard family Brassicaceae, but not all are species of the Brassica genus. Brassica is one of about 375 genera in the mustard family.  Some of the species listed are actually cultivars (domesticated varieties) of the same species of Brassica.  And what is going on with that capitalization on common names?  Lets capitalize every second word that starts with B?   

So how does this all work?  What is really the same genus and species of these delicious plants?  There are many cultivated plants in the Brassicaceae family (the mustard family). Brassica gave its name to the family Brassicaceae, like Rosa (roses) to Rosaceae (rose family), and Poa (bluegrass) to Poaceae (grasses). All plant families have scientific names that end with '-aceae', rather convenient when you try to tell them apart from other group names.

giant cabbages
Giant cabbages (Brassica oleracea) at a market in Uzbekistan. Photo by Lena Struwe (Creative Commons).
There are many, many species and cultivars of Brassica (or brassicas, as they are sometimes called in English). The cultivated brassicas are ancient and a result of a lot of breeding, selection, and crossing of genotypes, so their taxonomy is a bit messy within Brassica itself. Sorting out the current common names, their scientific names, and classification of the brassicas has to wait for another blog post (which is in the works). But, the summary is:

The Brassica genus is a member of the family Brassicaceae. Many other edible mustard plants are placed in other genera of the Brassicaceae. 

Saturday, December 26, 2015

Trader Joe's Real Mistletoe: a study in realness

This holiday Trader Joe's have been selling 'Real Mistletoe' in cute little old fashion-inspired boxes.  On the back of each box is stated "Our real mistletoe is hand harvested in the Pacific Northwest. Perserved naturally, it will last all season long. Hand from a doorway and steal a kiss from your sweetie!"
Trader Joe's Real Mistletoe. Photo © Botanical Accuracy.
Now, the first question we would ask, is of course, is it real? Well, it is a product of nature.  The plant inside the box is a real dried plant, not something molded and plastic.  So yes, it is real. (Of course plastic is also real, formed by atoms and electrons and chemical bonds, etc.  It all depends of your definition of 'real'. 

However, this is a dried plant dipped in paint. There is no information of what the paint contains, neither does it say anywhere on the package that the mistletoe is painted.  Instead it says 'preserved naturally' on the back of the package.  That brings us into the sticky territory of "what is natural?".  There are a lot of natural things in the world that we usually do not associate with the marketing term 'natural', such as uranium radiation, cancer, gold, DNA mutations, strychnine, and methane. Natural simply means it is something that exist in nature by itself, something we humans haven't created. There is no legal definition of natural.  There is no way to know if humans created this green paint on this mistletoe, or the dye or paint was mixed by 'natural ingredients'.  So, this is just another case of the use of 'natural' in marketing in a way that is ambiguous and uncertain. One thing is for certain though, a normal (natural) mistletoe has a greenish yellow or yellowish greenish color, and is never this dark green. Trader Joe's helped nature a bit with the color here.
Mistletoe dipped in paint. Photo © Botanical Accuracy.
Second, is it real mistletoe?   Now it becomes a bit tricky.  This is a mistletoe indeed, and mistletoes belong to a large group of species in the plant order Santalales.  The one historically associated with Christmas is the European species Viscum album, but it has cultural and mythological references all the way back to Viking times). The plant in the Trader Joe box is a mistletoe, but it is not Viscum album.  It is a species of Phoradendron, but which one is hard to determine due to the green paint on the leaves and flower buds. Several species of Phoradendron exist in the United States, and this is likely Phoradendron leucarpum (Santalaceae), which indeed is used as a Christmas substitute here in the United States. (It was ID'd with help from the Facebook group Plant Identification (intermediate-advanced) - Thank you!)
Phoradendron leucocarpum, not Viscum album. Photo © Botanical Accuracy.
So, in conclusion, is this real mistletoe?
Yes, it is a real plant, but painted. Yes, it is mistletoe, but not the species that is historically associated with Christmas kisses.  As usual, what is real really depends on your definition. And yes, it is a real mistletoe, a plant from the mistletoe order. Would I hang up this dried painted breakable mistletoe in my house?  Never. In my mind, this is not at all the real mistletoe of old Christmas traditions.

For more on botanical accuracies and inaccuracies on mistletoes, here is a link to a post from earlier, explaining the difference between mistletoes and hollies.

Friday, September 25, 2015

NYT taxonomic inaccuracies, again

I just sent this letter to the Corrections office at NYT, a newspaper that "welcomes comments and suggestions, or complaints about errors that warrant correction." Lets see if this taxonomic mix-up warrants correction in their minds.

"Dear New York Times Editor,

In a recent article about blue cheese, you write:
"To produce Roquefort blue cheese, for example, cheese makers mix Penicillin roqueforti into fermenting curds. "(Sept 24, online and in print)

No, it is not Penicillin roqueforti. It is Penicillium roqueforti. Penicillin is the antibiotic drug derived from some Penicillium fungi. This looks like a typical autocorrection mistake, added after Carl Zimmer wrote the article. Check with Carl Zimmer, I am sure he didn't write it that way.

As you surely know, words matter. Here is the link to the species page for this species in Species Fungorum.

Thank you"

Update - sorry, but the link to Species Fungorum seems to be down because their website is currently down.  Try a little later.  

Update 2:  HAHAHA!  New York Times has corrected the spelling to "Penicillim roqueforti".   Not sure if this is an improvement...but it certainly is still incorrect.  Dear NYT, each species on this earth can have one and only one accurate spelling of its species name. 

Update 3: OK, now it is corrected to the correct spelling of the species name. "To produce Roquefort blue cheese, for example, cheese makers mix Penicillium roqueforti into fermenting curds."  REad the article, is ia very good.
NYT also added a correction at the bottom of the article, but the correction does not refer to wrongly spelled scientific names in earlier versions, but to the isolating of the active compound: "An article on Tuesday about the evolution of molds used for cheese making referred imprecisely to the isolation of the antibiotic penicillin. While Alexander Fleming discovered penicillin in 1928, he did not isolate the active substance." 

Sunday, September 13, 2015

Dear New York Times, when will you start to care about taxonomic accuracy?

As a subscriber and frequent reader of The New York Times, it surprises and depresses me greatly that not more care is taken in checking facts and accuracy when it comes to scientific names of organisms and how these are formatted and presented.  Many of the problems and inaccuracies that we see in publications, media, and in web content are perpetuated by The New York Times, a publication that prides themselves in correcting any factual error, however how small.  But for taxonomic errors, they do not.  There are exceptions of course, such as Carl Zimmer's writing, but overall a general taxonomic fact checking is lacking, especially outside the Science section.

The main problems within biological taxonomy are:
  1. Non-capitalizations of scientific family names
  2. Capitalization of  species names
  3. Choosing to not format species and genus names in italics
  4. Wrong names for parts of organisms
  5. Images of the wrong species or other inaccurate image data
Lets dig into the details:

1. Non-capitalizations of scientific names of rank above species (orders, families, genera, etc.)

A the recent article in the Travel Section about the island of Runmarö in the Baltic archipelago featured entomologist Fredrik Sjöberg (NYT Sept 4, by Stephen Heyman). In the article, his study group, the hoverfly family Syrphidae, is consistently and erroneously written as syrphidae.
"Fredrik is exclusively interested in this family of insects, syrphidae, which is distinguished by an uncommon flair for disguise."
Oh, in case you wonder how a wonderful Syrphidae looks like (since the article doesn't show one), here is one:
unknown Syrphidae fly  P8170593croppedq
Unknown species of a hoverfly of the insect family Syrphidae, from New Jersey, USA. 
(PS. E-mail me if you know the species, I'd love to know.)
Creative Commons photo by Lena Struwe. (source)
Spelling Syrphidae as syrphidae is like spelling the entomologist's name as fredrik sjöberg, writing Oprah as oprah, or New York City as new york city.  There are a few exceptions of people that choose to spell their names without capitalizations, like bell hooks. But in the science world, nobody ever spells this without capitalization. Capitalization is not optional for the scientific names for families, orders, and other higher ranks of larger groups of organisms.  Why would NYT choose not to follow the scientific set standard?

The International Code for Zoological Nomenclature has very good, clear advice for how taxonomic names should appear in popular media, see this link.

(Of course, NYT refuses to put in the umlauts from foreign languages as well, but that is a separate matter. It is Sjöberg, not Sjoberg, and Runmarö, not Runmaro.  The meaning of the words change in Swedish if you remove the umlauts, so good luck googling some of these names :) . Wikipedia, on the other hand, correctly presents the words with umlauts, see for example Tomas Tranströmer, which NYT links to in the article above.)

2. Capitalization of species names
Just a few days ago a new hominid species was published, an astonishing and exciting find.  New York Times featured this prominently (Sept 10, 2015, in an article by John Noble Wilford): 
Headline of Homo naledi story in The New York Times.
Screenshot by BotanicalAccuracy.com.(link)
The new species of the genus Homo (our own genus), is called Homo naledi, but The New York Times capitalizes the word naledi in the title (presumably due to their editorial style using Title Case capitalization in headings). In the text of the article, the name is written as "Homo naledi" (with correct capitalization) throughout. The problem here is of course that the readers will think that the new species is called Homo Naledi, not Homo naledi (its true name), if they just see the title.

PBS' NOVA series does it better: " Homo naledi, Superhenge, and Humankind: NOVA Next Week in Review", so of course the species epithet can be in lower case letters even when using Title Case, but that means that you need to know something about taxonomic names.

For genus names, and for a species (which has a genus name and a species epithet, like Homo naledi) there is also really no choice in capitalization. According to the International Commission on Zoological Nomenclature:
"Following the principle of binominal names (i.e. composed of two names) a species name is a combination of genus name and species name. The genus name comes first, and must start with a capital letter, the species name second, with a lower case letter (Art. 28; Appendix B6). This shows the hierarchy between genus and species; a genus may include a number of different species." (link) (my bolding)
3. Choosing to not format species and genus names in italics
It is recommended to put at least genus and species names in italics, and in scientific literature this is nearly always done and for a good reason.  This is a lot easier today when books, magazines and newspapers are no longer typeset, but run on digital presses or completely provided as online documents.

The International Code of Zoological Nomenclature justifies this:
"In order to denote a clear distinction between scientific names of organisms and designations in common language, scientific names of all ranks should appear in the same distinctive, and preferably italic, type." (link)
New York Times article about a new snail species, Rissoella morrocoyensis, showing the name without italics. Screenshot by BotanicalAccuracy.com. (link)
As far as I can tell The New York Times never put any species names in italics. However, they do use italics for other items in the papers, such as identification lines on published letters to the editor (see question and explanation here), so it is not a technical decision but an editorial one. To highlight the value of taxonomy and science, and to clarify the proper use of taxonomic names for organisms, it is highly recommended to put all species names in italics when you can.

4. Wrong names for parts of organisms
Article about opium poppy harvest in Mexico in The New York Times.
Screenshot by BotanicalAccuracy.com. (link)
"Though shy, she perks up when describing her craft: the delicate slits to the bulb, the patient scraping of the gum, earning in one day more than her parents do in a week." (link)

Bulbs grow in the ground (usually), they formed by fleshy leaves on a very short stem at the base of a plant (Wikipedia has a good description). What is harvested on the opium poppies is the gummy sap that is oozing out of the fruits, the capsules, when cut.  In the printed version, one photo caption by New York Times also used the word 'pods', which has no precise botanical meaning. Would you call the tail of an elephant its trunk?  This is the same kind of mistake, and it is a ridiculous one to botanists and gardeners and generally educated people.

5. Images of the wrong species or other inaccurate image data
An earlier post on this blog featured the mistakes published in the review of the world-class foraging restaurant NOMA in Copenhagen (July 6, 2010, article by Franz Bruni).  The New York Times was notified that one of their photos of pine cones was incorrectly described as 'thuja cone', and with thuja being a toxic species, this was a mistake that certainly should have been corrected.  It was not.  It still features a pine cone listed as a thuja cone (see screenshot from today below). Not only are these two different species, they are also different genera and in different families.  I doubt that Rene Redzepi serves his guests potentially toxic thuja cones. 

The slide show accompanying the article about the NOMA restaurant features a pine cone in the photo, but it is described as a Thuja cone. Screenshot by BotanicalAccuracy.com  (link)
Why does taxonomic accuracy matter?
It is pretty simple. 
"In all cultures, taxonomic classification means survival. 'The beginning of wisdom, as the Chinese say, is calling things by their right name.' " E. O. Wilson
And that right name is the name of the species, the family, the organism's part, and so on.  We are 100% dependent on other species for our survival and future, and the taxonomic sciences make it possible to study these, be it microbes, parasitic diseases, edible plants, or pollinating insects.

The essay by Helen MacDonald in The New York Times (June 19, 2015) fantastically describes what happens when you can put words to the world around you, in this case using field guides.  You start to see things, remember things, care about things, and love things, and these things, be it forests, flowers, bugs or birds, are things that matters to humanity on large as well as personal scales. Names matter a lot.

The New York Times has a great opportunity to be a model and leader in public education about biodiversity and taxonomy among newspaper media.  It is not that hard, and it is something that is desperately needed in the US. Spell and format the scientific names correctly, actually describe what a hoverfly is in an travel article, do not publish an image saying a toxic plant is edible confusing foragers and foodies, know what plant part you talk about, and so on... Start being the standard for other media in the field, please.

I think that the sloppiness shown in The New York Times when it comes to morphology and species taxonomy would never be accepted when it comes to historical facts and names related to people.  For scientific facts this doesn't seem to matter to the editors, since fact-checking is lacking and pointed out errors persist and are not even corrected.

It would be very easy for The New York Times to contact a couple of biologists well-versed in taxonomy and systematics within their fields, hire them to be on call, and have them fact check all articles mentioning or showing species and organisms, regardless of newspaper section.  Scientific accuracy is of course needed in areas like travel, food, agriculture, and political news too; species do not stop to exist outside of the Science section.

References:
"What’s in a name? Scientific names for animals in popular writing" (ICZN)
International Code of Nomenclature for algae, fungi, and plants (ICN)
International Code of Zoological Nomenclature (ICZN)

Friday, July 10, 2015

No, you are not allergic to pretty flowers...

During this year's pollen season, the usual misinformation about pollen allergies crop up and grow fast in the media, online as well as in print.  Sneezing and astmathic people and their medications are often incorrectly associated with colorful flower imagery, when in reality very few people are allergic to the flowers that most of us know and love. But to advertising people, small tiny green flowers with dangly stamens might not be as photogenic as make-a-wish dandelion fruits and fields of flowering canola.
These ox-eye daisy flowers in this Shutterstock image on the Rocky Mountain Allergy Asthma Immunology website has absolutely nothing to do with pollen allergies. They are just pretty flowers. 
(Screenshot image by BotanicalAccuracy.com, source.)
A screenshot from a quick search on the keywords 'pollen allergy' on the photo website Shutterstock, shows an abundance of photos of insect-pollinating plants, flowering fields, and dandelion fruiting heads which has nothing to do with pollen allergies.  Some photos get it right but not the majority. (Screenshot by BotanicalAccuracy.com, source.)

Pollen, which are special small cells in seed plants that contain the male sex cells (no, it is not gross, just the fact), are produced in flowers and when the pollen lands on the female part of a flower or cone (the landing platform is called a stigma), the pollen germinates and a pollen tube grows into the female style and down into the ovary where it can fertilize the plant's egg cell and make a seed. This is not gross, just the facts, and in fact, if there were no pollen, there would be no fruits, no flowers, no seed plants. Seed plants are those that set seed, so that means conifers and flowering plants, but not ferns and mosses, because they have spores instead. Not all pollen causes allergies and neither does all spores.
Pollen grains from many different plant species shown in a photo from a Scanning Electron Microscope. (Public domain image from Dartmouth College Electron Microscope Facility via Wikimedia Commons, source.)


So, how does the pollen gets transported from the male to the female part in the flower? Most plants use animals as transport helpers (for bee pollination, etc.), but some plants have wind-pollination.  If you are adapted to use wind as the pollination method, then you are going to have some problems to overcome - first, wind is kind of random so you don't know where your pollen would end up, so you better make LOTS of pollen; second, you don't want your pollen to stick to anything that isn't the right stigma, so it needs to be dry and smooth and fly easily; and third, you need to make your pollen-sacs hang out far into the air without interference from large petals, so you can disperse your pollen with every little wind burst. These three evolutionary adaptations are seen in many wind-pollinated plants.  So, these plants produce an copious masses of dry, easy-flying pollen from small flowers with hanging pollen sacs.  This is exactly how birches, ragweed, grasses, walnuts, mugwort, elms, pigweeds, cottonwoods, and hickories spread their pollen around.  And these plants are the ones people who suffer from pollen allergies are allergic to (see caveat below).
Flowers of a grass, showing stamens with pollen sacs hanging out and spreading their light dusty pollen into our eyes and noses (and to other grasses). (Creative Commons photo by Dave Kleinschmidt, source)
Many people think they are allergic to goldenrod, this common, yellow-flowered fall flower, but it is insect-pollinated.  Plants that are pollinated by insects have 1) something that attracts the insect to the flower, usually sweet smell and bright colors, 2) sticky pollen that gets stuck on the insect, and 3) small amounts of pollen.  You can easily tell if a plant is insect or wind-pollinated by looking at its flower and checking if any pollen flies out in the air if you shake it (this only happens in wind-pollinated flowers).  There are also plants pollinated by mammals, birds, and other small animals, as well as water, but those are more rare.  In North America, the hummingbirds are the only birds that pollinate flowers.
VividLife illustrates their POllen Allergy Awareness article with a nice, invasive thistle, pollinating insect included.  Of course, it has colorful small pink petals (in a big flower head), sticky pollen, and is not something that easily causes pollen allergies. Another blatant example of wrong imagery in the pollen allergy area (Screenshot by Botanical Accuracy, source)
 So, when your neighbor says that he can't go outside because the dandelions are flowering, or there is a newspaper article about hay fever illustrated with a pretty flower, or your oldish aunt says she is allergic to the pollen of cut flowers in a vase, they will most likely be very wrong.  (Some people are allergic to the smell of pretty flowers, but that is different.)  Still, the misconceptions are flying like airborne wind-dispersed pollen in advertising, news media, and around lunch tables.
News article about herbal remedies for hayfever in The Epoch Times, May 21-27, 2015,
illustrated with a sneezing girl in front of a flowering canola field (which is not a wind-pollinated flower),
and with dandelion fruits blowing away below. (Photo by BotanicalAccuracy.com)
An other prevalent misconception shown in allergy imagery, even on the websites of medical and pharmaceutical companies based on science, is the (non-existent) connection between dandelions' fruiting puffy heads and allergies.  No, you are not allergic to flying dandelion parachute fruits and seeds, despite all those photos and ads showing exactly this connection.
Article from Mass Lunch & Allergy PC illustrated dandelion heads under the heading Pollen Allergy. Please note that the fruiting dandelion head not only has no pollen in it, it is also a fruit, not a flower. The grass would be the allergen to most hay fever suffers. (Screenshot by Botanical Accuracy, source)
In this image below, there isn't even one potential flower and no pollen source at all:

Freedom Home Care has an article called How to Keep Seasonal Allergies Under COntrol, and it is 100% illustrated with a no-pollen part of an insect-pollinated plant - Dandelion fruiting heads, again. Such misuse of images just creates confusion and makes the public afraid of real nature. (Screenshot by Botanical Accuracy, source)  

 So, why does these image mistakes matter?  It is just a picture, right?  Well, they matter a lot.  The public reads the information and associates the allergies with the images that are used to illustrate them.  Allergies means medical problems (bad stuff). We start to think allergies when we see canola fields, blowing wishes with dandelion heads, and pretty flowers.  It is 'guilty by association' and just more of the fear of nature that is spread around in media.  Fact checking should not only be for the words but also for the images that goes with the words. Some allergy doctors and pharmaceutical companies are just as guilty as photo databases in this area.

Caveat: This blog post is based on what most people are allergic to that react to pollen.  You could become allergic to nearly anything, so a small percentage of people could be allergic to tulip pollen, rose petals, and goldenrod pollen, but that is very, very rare.  When testing for allergies, it is the wind-pollinated plants that count.

Links for more information:
American College of Allergy, Asthma & Immunology: Pollen Allergy: Be aware that this webpage has some overly simplistic descriptions about the biology and biodiversity of plants.  For example: "Pollen is very fine powder that comes from trees, grasses, flowers and weeds." and "When a plant begins to flower, its pollen goes into the air."  They need a biologist fact checker.  No need to make things so simple fo the public that is becomes wrong.

Many thanks to KS for medical allergy testing information.