Plant Resemblances

Criminal sketches have been on my mind this week.  How does the police artist help the victim to verbalize someone’s face?  What are the best words to describe the jaw, mouth or eyes?  What features exactly make one face resemble another face?  And how does the crime artist help the victim remember?  I have no secret fantasy of becoming either an artist or a forensic investigator, but I would love to be able to describe plants better, and I admire the ability of botanists to be able to clearly state and remember the differences between closely related plants.  Keying out plants with a professional botanical key is the way that I was taught to learn the characteristics that separate one species from another species.  My skills  using botanical keys are still quite weak, and I am looking for new tools to help me.

More and more of my students love to take pictures with their cell phones to help them learn the organisms and anatomical structures that we cover in class.  Some years ago, I delved into photography too, taking a wonderful summer class on how to use a DSLR camera. I enjoyed taking pictures, and I was surprised and a little disappointed when I came across a psychology paper that provided evidence that taking photographs might make it less likely that the photographer remembers the event or subject (Heckel 2013).  The photos that my students and I are taking in lab or field might actually be making it harder for us to learn botany!

Why would taking a photograph inhibit or “impair” memory?  Maybe the photographer unintentionally relinquishes the work of remembering to the camera and its digital memory card?  Or maybe the photographer is so distracted by which buttons to push that their mind is distracted away from the details of the event or subject?  If my students are determined to take pictures, could I help them make the pictures more effective by having the student label the photographs? or revisit the photographs?

I’ve always heard that it helps students learn better if they draw what they see through the microscope.  If taking photos impairs the memory, does that mean that drawing will improve the memory?  I’m sure there are research articles out there with data that shed light on this question, and I would like to find those articles someday.  In the meantime, I have decided that I would like to encourage and help my students and me draw more in lab. The problem is that I don’t draw well, and I have only a few tips that I can give students on drawing.  I was excited when a local artist spoke about nature journaling as a way to pay more attention to the natural world.  She recommended that I look at the book “Laws Guide to Nature Drawing and Journaling” by John Muir Laws, which is an absolute pleasure to peruse.  I also found an online course in Botanical Illustration and signed up. Hopefully I will manage to write a few future blog entries on my insights from the course and my anecdotal journey to see if drawing helps me remember plants.

This spring I have been watching my Thalictrum (meadow-rue) and Aquilegia (columbine) grow, and finding that even though my brain sees a resemblance between the leaves of these two plants species in the buttercup family, I am not sure I can verbalize that similarity.  My new favorite book is:  “Spring Wildflowers of the Northeast:  a Natural History” by Carol Gracie.  Gracie is really amazing at describing in words what makes certain plants resemble each other.  She says that the leaflets of meadow rue are “scalloped”, having an edge marked with semicircles.  That’s it! Columbine also has leaflets in three with scalloped edges too!  But there is more to it - the leaves also seems to be positioned in a similar way.  How would I verbalize that similarity?  Maybe an art class combined with botanical keys and Gracie’s book will help me guide me and my students to recognize and articulate plant resemblances better? Members of the same plant family often share characteristics.  Could this help me learn plant families better? Certainly drawing floral diagrams is supposed to help with the learning of plant families, but I like the idea of drawing not just the flower but the whole plant.

Police artists certainly help the non-artist describe and even remember characteristics of people.  I hope that the botanical illustration class will help me become better at describing and remembering plants.

Heckel, LA.  2013.  Point-and-shoot memories: the influence of taking photos on memory for a museum tour.    Psychological Science 25(2): 396 – 402.

Gracie, C.  2012.  Spring wildflowers of the northeast: a natural history.  Princeton University Press, NJ.

Laws, JM.  2016.  Laws guide to nature drawing and journaling.  1st Edition.  Heyday Books, CA.

Learning Gymnosperms: Chamaecyparis Cones

Very little in plant identification is easy:  so many terms, so much intraspecific variation, such subtle differences, and such minute characteristics to try to examine, even a hand lens is sometimes insufficient. If those challenges weren't enough, one huge roadblock is the frequent need for reproductive parts.

Conifers are no different than any other plant group in the fact that reproductive parts greatly improve the ability to correctly identify a conifer to genus and species. In my attempt to learn more gymnosperms, I blundered upon a tree that superficially looked like it might belong in the genus Thuja.  This tree is on the path of my daily dog walk, and I have never paid enough attention to realize that the tree had cones: very tiny globular cones.  If I hadn't noticed the cones, I would never have realized that this tree didn't belong in the genus Thuja.  These are not the best pictures, but they give you some idea of how different these cones are from the cones of Arborvitae.

Feeling overwhelmed isn't a nice feeling, and it is very easy to feel overwhelmed when trying to become better at plant identification. In some ways, conifers are a good group to tackle. Some of their nice features are that they often have green tissue year-round, and their cones are present much longer than most angiosperm flowers.  (In defense of angiosperm tree identification - I've learned that twig characteristics are at least, possibly more, reliable than leaf characteristics so winter identification is possible even without leaves.) There are many fewer families and genera of conifers to sort through than genera and families of flowering plants.  I suppose one disadvantage to learning conifers is that there are so many cultivated conifers: artificial breeding and selection by humans have led to stunning differences in size and structure even within the same species, and furthermore, many conifers are planted in areas very far from their native range. With regards to intraspecific variation in cultivated conifers:  It was quite a shocker for me to peruse the Encyclopedia of Conifers: A Comprehensive Guide to Cultivars and Species by Auders and Spicer!  This encyclopedia has lovely pictures and descriptions, and I recommend it to anyone.

Here's a very simple key that nicely separates Chamaecyparis from other conifers:
https://www.amnh.org/learn/biodiversity_counts/ident_help/Text_Keys/conifer_key.htm

Teaching Botany with Tuning Forks and Buzzing Toothbrushes

At a recent bridal shower, we played “What’s in your purse?” where participants gain or lose points depending on funny items they do or don’t have in their handbag. I missed out on points for lipstick and underwear, which I don’t carry, but I was thrilled to receive extra points for my toothbrush.  I chose not to enlighten the party on the reason why I carry a bristle-less electric toothbrush (not for the highly respectable goal of better tooth care).  I carry a toothbrush for the same reason that I also carry a tuning fork (even though I don’t tune anything but the radio).  Why do I carry an electric toothbrush and a tuning fork? Because they both buzz!

Buzzing devices like toothbrushes and tuning forks are a fun way to introduce concepts of pollination to students.  Tuning forks and electric toothbrushes have been used for years by farmers and scientists for artificial pollination, and I am certainly not the first to use these tools this way.  For one especially neat example of the use of tuning forks by citizen scientists, see this video by the Urban Pollination Project.  The Urban Pollination Project conducted a study comparing several experimental treatments of urban tomato plants, and one treatment involved tuning-fork assisted pollination. With the help of tuning-fork equipped citizen scientists, their study provided published evidence that wild urban bees support and enhance the productivity of urban agriculture.  

The buzzing and whining sounds of wild bees and flies are attributable to their rapidly contracting flight muscles and/or wings, and those buzzing sounds help release pollen by shaking the pollen out of the sac-like male reproductive structures called anthers.  Anthers break open or rupture to release their pollen in a process called “dehiscence”.  Anthers most commonly rupture along a long slit (“longitudinal dehiscence”) and the pollen spills out, ready to be smeared on any insects that visit the flower.  In a smaller subset of plants such as tomatoes and the lovely prairie flower shooting star, the pollen leaves through small pores or very tiny slits (“poricidal anthers”).   Flowers with poricidal anthers frequently display “Buzz Pollination”, and these flowers rely on the vibration of a visiting insect to disperse their pollen grains.  Buzz pollinated plants shower their flower visitors with pollen that is vibrated out of the small holes in the anthers (see this PBS video on “Buzz Pollination”).  Flowers release more or less pollen depending on the frequency of the buzzing sounds.  In contrast, plants with longitudinal dehiscence probably rely more on tactile contact than vibration frequency to powder their pollinators. 

Plants have not only evolved traits that attract pollinating insects, but they have also evolved floral traits that protect their flowers from insects that might take too much of their pollen or nectar and from insects that steal nectar and pollen without providing any pollinating benefit.  In the case of buzz pollination, bees are unlikely to waste excessive energy buzzing for an extended time at one flower, and that means that a single bee won’t take all the pollen out of an anther in one visit.  By saving some pollen for the next visiting insect, the plant obtains yet another chance to pass along its pollen genes.  Buzz pollination also prevents tiny insects that can’t carry much pollen from stealing pollen because these insects are just too small to make the right buzz sounds.  The story of the evolution of floral morphology may be as much about the “bad guys” (for example, thieving ants and beetles that steal flower rewards without ever moving pollen to another plant) as it is about the “good guys” (such as bumble bees that are often quite successful at distributing pollen).  Most of us know at least a little bit about the good guys in pollination (the birds and bees), but less about the bad guys.  As a graduate student, David Inouye’s article “The Terminology of Flower Larceny”  helped to enlighten me on the diverse array of flower enemies that have probably influenced floral evolution.  When I discovered buzz pollination, I knew I had found a system that is ideal for discussions with students on the delicate balance between being a good pollinator that helps with seed production versus a flower enemy that exploits a flower reward and steals excessive pollen.  When I discovered that tuning forks and electric toothbrushes can mimic buzz-pollination, I was excited to take these tools to the classroom. 

Demonstrating pollen leaping out of the anthers of a flower when touched with a vibrating device can sometimes catch the attention of animal-centric students.  Arming students with their own tuning fork and sending them to a field to buzz their own flowers provides students with an engaging and hands-on botany learning experience.  You can buy sets of 9 or more tuning forks from chiropractic and scientific suppliers or even amazon.com.  Which turning fork is best?  The Urban Pollination Citizen Science Project had participants use middle C (C261.6 Hz) tuning forks, but other tuning forks will also work.  Teachers can even construct artificial anthers out of talcum powder, toothpicks, and tiny hand-made envelopes or packets with pin holes that allow students to simulate buzz pollination on rainy days when collecting pollen-ready flowers outside may be inconvenient or impossible. 

Adding a tuning fork or battery operated toothbrush to your handbag or backpack may not help you win the bridal shower door prize, but these are great tools to have handy for a fast and easy botany demonstration and associated fun conversations about mutualisms with your students.

References

Galen, C. 1999. Flowers and enemies: predation by nectar-thieving ants in relation to variation in floral form of an alpine wildflower, Polemonium viscosum. Oikos 85(3), 426-434.

Harder, L.D. and R. M. R. Barclay.  1994.  The functional significance of poricidal anthers and buzz pollination:  controlled pollen removal from Dodecatheon.  Functional Ecology 8: 509-517.

Inouye, D.W., 1980. The terminology of floral larceny. Ecology 61, 1251–1253.

Pearson, G.  2015.  Bees are great pollinating flowers – but so are vibrators.  Wired Magazine https://www.wired.com/2015/05/bees-great-pollinating-flowers-vibrators/

Potter A. and G. LeBuhn.  2015.  Pollination service to urban agriculture in San Francisco, CA. Urban Ecosystems. 18:  885–893

Puterbaugh, M. 1998. The roles of ants as flower visitors: experimental analysis in three alpine plant species. Oikos 83(1), 36-46.

Stranden, A.  2016.  This vibrating bumblebee unlocks a flower's hidden treasure. Prod. Josh Cassidy. Perf. Amy Standen. Deep Look. PBS, Accessed 23 June 2017. https://youtu.be/SZrTndD1H10 . 

Seems Like Just Yesterday that the Sarvisberry Bloomed

I enjoyed reading an ecard quote this week that, "For teachers, the month of August, is just one long Sunday night."  Isn't that what it feels like as the first day of classes approach?

I started looking through my pictures from this summer.  From all the way back in May, I have a picture of serviceberry.  When visiting my brother-in-law he pronounced it very differently.  I thought it was just his Windber twang!  I discovered that his common name was more correct than mine and was spelled differently too, even though it was the same tree.  He called the tree sarvisberry.  I took the picture of this tree in May, long before conversing with my brother-in-law.  On the ride home from Windber, I read about this tree in the book:  Trees of Pennsylvania: and the Northeast by Charles Fergus.  The book is a wonderful way to get to know particular tree species; reading it, I felt like I was getting to know my friends better.

Serviceberry is probably a modification of the older name sarvisberry, which may be a name that settlers gave to the tree because the fruits resembled the Sorbus from their European homes.  Serviceberry on the other hand, has a relevance all its own.  The tree blooms early, about the time that the ground might have thawed enough to bury the dead, several hundred years ago.  The tree is also called shadbush because it blooms at the same time that fish (shad) were migrating up the river.  (And a quick YouTube search, led me to this video that suggests that not only are the fruits edible, a fact that my brother-in-law had told me, but so too are the flowers.)

Today as I reviewed my pictures from May, I felt nostalgia for the early parts of summer.  Here are a couple of my pictures. Ah, to return to the early days of May with the whole stretch of three months of summer ahead of you!

The genus is Amelanchier, and the family is Rosaceae.

Lots to Know about Willows

The willows are in bloom; they are very early bloomers, beat only by some even earlier flowering plants like skunk cabbage.  Willow flowers don’t, to my knowledge, have petals, and they often bloom before their leaves appear. If you aren't paying attention, it’s easy to miss the entire flowering period of willows.  For a teacher, if you are interested in using willows in your classroom, it may be worthwhile to mark willows in April as to whether the plants are male or female.

My daughter challenged me to find one hundred and one facts to know about willows.  Probably possible, but rather than be boring, I have picked a few favorites in hopes that they might inspire me to think creatively about how to use willows more than I currently do in the classroom. I found this site with some of the great “big picture” facts about willows highlighted:  http://www.people.fas.harvard.edu/~jsavage/Willows.html

To me, willows are a background plant; if you study them enough they do stand out, but if you are just riding your bike down the road, they just look like a bunch of shrubs.  Like every plant (and every person), willows have their own interesting stories to tell but you may need to ask and listen to know the story.

1.  Willows are dioecious; some plants are male,  and some plants are female.

2.  Some willows have been reported to be ambophilous, using wind and insects to disperse pollen (Meeuse, 1978).

2. Over twenty species of willows can be found in Pennsylvania.  http://www.paflora.org/

3. Changes in the chemistry of willow plants may help explain cycling in Lynx populations.

Bryant JP,Wieland GD,Clausen T,Kuropat P. 1985.  Interactions of snowshoe hare and feltleaf willow in Alaska. Ecology 66: 1564–1573.

4.  Willows often like wet areas.

5.  Willows make compounds related to aspirin (Salicylic acid).

6.  Willows are related to Aspen, and I believe that I see the similarity when looking at the hairy buds on the branches. 

7.  Some gall-making insects attack willows, and there are reports that herbivory may differ between male and female plants. Furthermore, willows interact with many insects.  Wonderful pictures can be found here:

http://wanda.uef.fi/biologia/nyman/IOWexternalfeeders.htm

8.  You can make a cheap rooting solution by soaking severed young willow twigs in water for several weeks & then using that water on the roots or cut stem of another plant.

Willows in the classroom?

The capacity of willow plants to make rooting hormone certainly opens many doors to student experiments. 

The vegetative and flower buds of willows, especially “pussy willows” are quite appealing to students – so they provide an opportunity to investigate plant stem anatomy.

Dioecious nature of the plants provides an opportunity to ask questions about sexual dimorphisms in general.  Can you detect differences in allocation to resources between male and female plants? Why do male plants allocate resources different from female plants? Can  you detect differences in herbivory between males and females?

Thinking About Harry Plants While Feeling Harried

Many words exist that describe hairs or harriness of plants.  Here are some that I found:

trichome
pubescent
tomentous
villous
indumentum
wooly
pilose
colleter
felted
floccose
glochid
hirsute
hispid
hispid
penicillate
puberulose
sericeous
strigose
stellate
arachnoid

How are hairs adventageous to plants? In Johnson (1975)'s  review, he concludes that the propensity to make hairs is quite widespread in plants, and suggests that the ability to make hairs is probably genetically available to most plants.  Perhaps in line with the Gould Lewontin's famous essay "The Spandrels of San Marcos", Johnson (1975) seems to hint that hairiness in leaves and stems could be just a correlational effect, a trait that exists more due to the need for root hairs than for any function to leaf and stem hairs.

On the other hand, Johnson (1975) reviews quite an array of advantages that have been proposed for leaf and stem hairs.  Hairs on leaves may reduce water loss from leaves.  Hairs change the reflectance of a leaf, and also the wavelenghts of light absorbed by a leaf.  Taking this information together, hairs on leaves could affect leaf temperature, photosynthesis, and water retention.  Hairness of plants may make them less palatable to predators (Johnson, 1975).  Hairy leaves are not only harder to eat and chew, but they may be less ideal for laying eggs or even for the growth of fungi and bacteria (Johnson, 1975).  Finally, Johnson (1975) suggests that hairs on leaves increase the surface area and may influence excretion of gases, fluids, inorganic or organic solutes.

Today I post a picture of lamb's ear, Stachys byzantina .  This plant is loved by many gardeners and by my children.  Wikipedia suggests that it is native to the middle east.  This plant is a member of the Lamiales or Mints.  Like other members of the family, Stachys byzantina has a tubular flower, five-fused petals, and a corolla that is bilabiate and appears to have two lips.  The bilabiate shape of flowers has evolved more than once so the shape of the flower is perhaps not the best way to identify family.  There are many interesting chemicals and oils found in members of the Lamiales, and likewise members of this family are often aromatic.  The leaves of members of the Lamiales (including Stachys byzantina ) are often opposite, and the stem is often square.  The style of many Lamiales flowers arises from a depression in the ovary.

Click on this picture for a bigger view of Stachys byzantina

Life is busily speeding along, and I can knot afford to spend more than a brief moment on untangling hairy plants; I'm just too harried!   (Comb on, there must be better puns for this topic!)

Gould, Steven J and Richard C. Lewontin. 1979.  The spandrels of San Marco and the Panglossian paradigm: A critique of the adaptationist programme. Proceedings Of The Royal Society of London, Series B, 205: 581-598.

Johnson, Hyrum B.  1975.  Plant pubescence: an ecological perspective.  The Botanical Review 41: 233-258.



Burr Cucumber and Early Successional Environments

Where are all the blogs that I planned to write?  They are lost in the rush of my life.  I appear to have personality traits that are advantagous only in an often-disturbed, early successional environment. I am sloppy, rushed, and eratic.  These traits work fine when the critical deadlines are yesterday, but don't work so well for long term endurance and planning ahead.

I am choosing to blog today about Burr Cucumber.  It seemed to be appropriate that I should blog about an early-successional plant that does well in disturbed environments, and that seems to appear out of nowhere, rush through its plant-life and disappear just a quickly, unable to survive any serious competition or bad weather.

Burr Cucumber is in the genus, Sicyos . How is that pronounced? I wanted to say it "sick", but upon going to this site: I found that the c sounds like an "s".  At the end of the summer, burr cucumber suddenly appeared on our back porch, and in what seemed like just a matter of days, it was lush and big and taking over.  While the plant grew very well, at the first bit of frost, it appears to have died.  (In contrast, our garden pepper plants are still  hanging in there!)  The burr cucumber seems to have more speed than stamina and endurance. The genus belongs in the Cucurbitaceae or Gourd family.  Like some other members of this family it has hairy stems, palmate leaves, and a propensity to climb.  Although the burr cucumbers are not edible, its relatives, the  pumpkins and squashes (both Cucurbita pepo)and cucumbers (Cucumis sativus) are edible.

I haven't keyed out the plant in my backyard, but I suspect that the species growing there is Sicyos angulatus - which is a native weed, and some sites regard it as invasive to fields of nonnative crops. 

This weed reminds me of several topics that I emphasize in my classes.  I bring up climbing plants when I talk about convergent evolution.  Tendrils are one of  many homoplastic climbing traits that plants have evolved repeatedly to solve the same problem:  the need to raise the photosynthetic leaves above the nearby competition.  This plant also displays traits that are advantageous in an early-successional environement:  grow fast and put most of  your energy into growth and reproduction and none into storage; this plant is an annual.  It has not saved any resources to survive the winter; it has reproduced and died.

My life seems to be favoring the "do things quickly"strategy - or at least I feel a pressure to focus more on short-term results than long-term solutions.  And on that note, I redirect my attention away from the pleasant long term goal of learning more about plants, and return my attention to getting a cup of coffee so that I can work faster, burn out sooner, and meet those immediate deadlines of my often disturbed daily routine.

Pictures of Sicyos on my back porch: