Welcome to the wonderful world of weedy plants!
Weeds are superevolutionary products of human civilizations and activities - without humans there would be no weeds, just wild plants.


Wednesday, November 19, 2014

Tweet, tweet, tweed, weed...

We asked our students to come up with come good tweets about what they learned in our Byrne 2014 seminar about weeds, and here is the result!
I've learned that weeds and flowers are no different biologically. 

Weeds are awesome.

Weeds are like onions. Onions have layers. Weeds have layers. They both hve lauers. #weedstho

I definitely have a new appreciation for weeds. Except for that unidentifiable grass. #Istillhavenoideawhatthatwas

Hated for the wrong reasons #weeds

Weeds, the hipsters of the plant world. People don't understand them and want them gone. They're still pretty cool though. 

Nothing about kush. Everything about dandelions #notthatkindofweed

I ate things that I probably stepped on earlier, and liked it! #dandelionicecream #weedsarecool

Weeds are not bad because they taste great on pizza and in every other type of food also it is natural and healthy #weedsforlife #weedsarecool

Thanks students for a great class!

Kudzu Has Outsmarted Us

Guest post by Patricia Chan, a freshman in 2014 Byrne seminar on weedy plants

Let me tell you about Pueraria montana var. lobata —it is a crazy, crazy, invasive weed.  This plant, commonly known as Kudzu, but also known as Japanese arrowroot, is a plant in the pea family, Fabacaeae.  You may be thinking: “it’s related to the pea, I guess it probably climbs” (ok you probably didn’t think that, but bear with me).  Well if you were thinking that, you are more than right.  Kudzu is an aggressive and skillful climber, much to the dismay of property owners of the southern United States. But before I tell you about this insane plant, let’s discuss how to recognize it in the wild.

File:Kudzu field horz1.JPG

CC Gsmith 

If you happen to stroll around anywhere in the southeast US and encounter a large green mass where there probably shouldn’t be one  - Congratulations!  You have found Kudzu. Kudzu is a very distinguishable plant from afar due to its tendency to cover large areas.   Up close, it may be slightly harder to recognize.  It’s got compound trifoliate leaves (meaning it has three leaflets on one stem) with a varying number of lobes on each leaflet from 1-3 lobes.  The leaves are fuzzy by the way, like a rabbit.  Like a very small, green, coarse, leaf-shaped rabbit…  The long vines cling to surfaces with little brown bristles that it uses to grapple over trees and buildings.  The flowers are a lovely deep pinkish purple hue and grow in clusters.  That’s nice.

photo by Peggy Greb, public domain 

Anyway, now that you know how to point out Kudzu when you see it, let’s learn more about how it behaves.  Kudzu has a very aggressive growing habit; in the right conditions, it can grow up to one foot per vine a day.  Monstrous.  People have reported losing entire cars to masses of Kudzu because they were parked for a few days.  How crazy is that?  In nature, Kudzu is considered a nuisance because it can envelop entire trees in short periods of time, killing forests by crowding out the light.  What a horrible plant to bring places, one may assume.

With that in mind, how did Kudzu even get here, not being native to this continent?  Maybe by a shipping mistake or a tourist?   No, in fact, Kudzu was brought to this country intentionally from Asia for ornamental and erosion prevention purposes.  That’s right, us humans spread this plant ourselves.  The sad truth is that we didn’t do the research we should have to ensure that this plant didn’t damage our ecosystems the way it did.  We just brought it over on a hypothesis and a whim.

This just goes to show: it’s wise not to mess with the natural order of things.  Not to say that it’s impossible to introduce a foreign species successfully, but a lot of heavy research must be done before it happens to make sure a monster isn’t unleashed.  All in all, Kudzu isn’t actually a wholly evil plant.  It carries medicinal purposes, has beautiful flowers, and it really does prevent erosion.  And in the end, it only behaves the way it because these characteristics have helped it to survive and reproduce in the past.  Kudzu acts to survive, and it just so happens that it is really good at doing that in the US.  What we need to do, however, is be more careful to monitor this kind of thing when considering what exotic plants to put where.  We need to be smart in our ecological decisions.

Weeds: The Public Census

Guest post by Tina Thawani, a student in the 2014 Byrne seminar on weedy plants


            A couple weeks ago I had to “Combat Plant Blindness” by showing someone a weed, identifying it, and telling them a bit about weeds in general.  I ran down a hill on Livingston campus and tugged on a plant that looked a bit like Queen Anne’s Lace.  I brought it back to my friend Rachel who was staring at me as if I was crazy, and explained that it was considered a weed.  She took one look at it and exclaimed, “Really? I didn’t know weeds could be so pretty.”  I then went on to explain to her the basis of the seminar: weeds, and the false image society has of them.
            Intrigued, the next day I decided to ask my roommate and a couple other people in my hall how they felt about weeds, as a miniature survey.  After hearing their initial reaction, I explained to them the real story behind weeds, then asked them again.
            I first asked Nikki, an accounting major from across the hall.   “So what do you know about weedy plants?”
            Nikki stifled a groan.  “Ugh, they’re so annoying.  I have to weed them out myself at our garden at home and it’s a lot of work to manage. Why?”
            “Well,” I started, “The term weeds is actually a subjective term, characterized almost exclusively by the fact that we humans don’t want that plant in our lawns and fields of view.  They tend to grow in abundance, and since they grow in places they weren’t planted, it’s actually an indication that they are evolutionarily more fit for the environment they occupy.  Many plants we call weeds, in other countries are considered useful and are even appreciated; for example, a weed called chicory can be used as a coffee substitute, and it is in many countries.  A weed called Queen Anne’s Lace is actually in the same species as carrots.  A weed called fennel can make nice after-meal mints, and mulberry, a woody weed, can be used to make paper and medicinal tea.  Sometimes, plants aren’t invasive, which means that they spread everywhere quickly, in their native countries, but when they’re brought to a different country through human interference, they react differently with the climate and habitat. Basically, most weeds happen solely because of us.” 
            “That’s cool,” Nikki said, nodding.  “That kinda opened up my definition of what weeds were, I never really saw it like that… but it doesn’t change the fact that I have to go through all this work.  I wish more people cared less about their gardens being perfect so that we could fully understand the role and possible benefits of weeds in our garden.  If the weeds weren’t so invasive, though, I don’t think they’d be so bad.”

            Next, I asked my roommate, Sarah, a biology major.  “What do you think of weeds?”           “Umm… weeds…they always get in the way of gardening and outdoorsy stuff like that right?” she said.  After giving him the same spiel I gave Nikki, her viewpoint had changed.
            “You’re right! They’re evolutionarily better, and I believe in evolution.  They’re annoying, but hey, they’re plants, and they have the same right as other plants.”

Lastly, I asked a guy who was playing pool with his friend in the first floor lounge.  “What do you think of weedy plants?” I asked. 
            “I think it should be legalized.  It’s better for the economy.” he said, as he twirled his pool stick. 
            “No, I mean, the other type.  Not marijuana,” I said with a sigh. 
            “Oh! Oh. Those.  Sorry. Uh… weeds… well, they’re stupid and annoying.  My dad has someone come in and weed the garden every month or so, cuz they grow so fast!”
            After he heard my speech, I asked him again - “So, what do you think of weeds now?”
            “Wow, I didn’t even know there was more than one type of weed.  Wait, so if they’re useful and diverse, why do we insist on planting our own flowers and removing the one that can grow there easily?  Ugh, Americans.”

            One thing I’ve confirmed from this experiment is that nobody really initially has a positive view, or even a neutral view, on weeds.  Yet, once they learn more about them, people are more sympathetic towards them.  I believe if people took my seminar on weeds, they too, would have a completely different viewpoint on weeds than they did before.  Like in most aspects of life, education is the cure-all.          

Thursday, November 13, 2014

How Weeds Become Weedy

Guest post by Patricia Chan, an undergraduate freshman in 2014 Byrne seminar on weedy plants
           
What is a weed?  Generally, it’s an incredibly hardy and pervasive plant that we as humans deem undesirable for our purposes.  Whether it’s a thorny bush in our yard, a vine stealing sun from our crops, or the wildflowers in our lawns that “ruin” the uniformity of our grass—weeds are what we make of them.

How to tell if that plant is a weed:
·         People don’t like it
·         It’s hard to get rid of

Honestly, I could talk all day about how we define plants as “bad”, “harmful”, and “ugly”, but enough about that.  Let’s discuss the second aspect that makes a plant a weed: their ability to survive, reproduce, and even flourish in the most trying conditions.  If you look at it this way, weeds are pretty incredible.  They manage to succeed in environments that limit all others and they seem pretty happy doing so too. 

In terms of ultimate hardiness and survival, weeds are the all-out winners.    They have and they continue to outwit other plants and animals every day, everywhere.

There are hundreds of adaptations that weeds evolve to outcompete other plants and evade humans, but my favorite adaptations are their aggressive defenses.  The parts of a weed that shout “I AM PREPARED” in the face of adversity.

Some plants produce oils that target and irritate animals trying to disrupt them- a commonly known one being poison ivy. 

Some plants produce thorns- that’s normal.  But then some plants produce serious don’t-you-even-think-of-touching-me-thorns.   That’s the case in the honey locust.  While its thorn-less variety is commonly grown around urban areas, its natural state is feared and frowned upon by most.  It has thorns covering the entire tree, with thorns growing off of thorns growing off of thorns.  No human or animal would ever want to mess with that tree.

cc Greg Hume
above: honey locust thorns growing straight off the thorns growing off of the trunk
.http://upload.wikimedia.org/wikipedia/commons/thumb/3/32/HoneyLocustThorn.JPG/220px-HoneyLocustThorn.JPG

Some plants, like the black walnut, go so far as to emit chemicals from their roots that kill plants around them and prevent others from growing.  Because of this, the black walnut tree can enjoy its nutrients and sunlight uninterrupted by close competition.  It is also because of this that the tree is considered a horrid weed by gardeners and farmers alike.

Acacia trees are yet another weedy and plentiful species with clever survival strategies.  In addition to their thorny defenses, they use chemicals to communicate with each other when threatened .  They are responsible for confusing countless scientists were studying unexplained antelope die-offs seemingly.  It turns out that when the antelope munched on the acacia leaves, the tree signaled to itself (and others) to begin producing toxins to reduce the threat. That’s impressive.

Any way you put it, weeds are an amazing achievement.  Most of us gardeners, farmers, homeowners, or bystanders may not appreciate weeds on a surface level, but let’s now recognize all the work in evolution that led them to where they are now.  Sure, invasive, mass spreading weeds may not always be conventionally beautiful, but there’s a reason why they’re hard to get rid of: we selected them to be that way. 

Next time you see that weed that seems to always come back, take a moment to applaud it as an impressive feat of nature, because that’s what weeds really are: they’re tough.