Confusing PLANTS / Taxonomy Misconceptions

Comment on a FB post of mine with Datura wrightii essentially said “get rid of it!” so I looked for something else poisonous to respond. Morning glory seeds turn out to be quite dangerous if ingested.

2 Likes

It has a corymb of flowers. Very pretty structure once the flowers are history.

Which plant taxonomy do you keep forgetting, or getting confused by?

I often get confused when German botany uses different terms. For example, in German “Gras” means poales, and then there’s “Süßgräser” (poaceae, grass in English) and “Sauergräser” (cyperaceae, sedges). So in English, when someone tells me this carex I found is not a grass - that is quite confusing because in German it is a grass.

Similar with mosses. In German, “Moos” generally seems to include “Laubmoos” (literally “leaf-moss”, Bryophyta, moss in English), “Lebermoos” (“liver-moss”, Marchantiophyta, liverworts) and “Hornmoos” (“horn-moss”, Anthocerotophyta, hornworts). When I first moved to Germany I corrected people who were pointing out mosses to me, saying things like, this is not a moss, it’s a liverwort - until I realized it was me who was confused, by language.

4 Likes
  • I have heard a certain number of people stating that Quercus ilex is not an oak just because they only knew its Italian common name (leccio).

  • Many people mistake the Mediterranean woodlands for the Mediterranean maquis, that is, in theyr opinion, every vegetation patch made up of trees is a maquis.

  • In some cases I have noticed that people make confusion between native/alien plants and wild/cultivated plants

2 Likes

This reminds me of this – I quote “Flowers of the conifers (pine, spruce, fir, and other cone-bearing woody plants) are called strobili, which means small cones.” –

…and this paper (Defining the limits of flowers: the challenge of distinguishing between the evolutionary products of simple versus compound strobili; 2010; Paula Rudall and Richard Bateman) that I’m still trying to wrap my head around. :exploding_head: :face_with_spiral_eyes:

One thing I’ve been trying to understand from the perspective of morphology (and its associated philosophies) what really is the difference between a flower and a strobilus. Why is a flower essentially a strobilus but a strobilus is not a essentially a flower?

I’m coming to learn that morphology, just as much as taxonomy, is just an application of human philosophical reasonings onto the things we observe in the real world around us, things which are unrelenting non-conformists. (But then again, what science isn’t boiled down to just that.)

5 Likes

I think botanically it’s very simple - if its a flowering plant (angiospermae) it’s always a flower no matter what it looks like. Otherwise it cannot be a flower (no matter what it looks like).

1 Like

That sounds like a tautology.

2 Likes

A better botanist could correct me, but I think one key morphological (or ontogenetic) difference is that in flowers, the ovary develops into a fruit that encloses and contains seeds. Not always fleshy, culinary fruit that humans like to eat, of course! But botanical fruit one way or another.

On something like horsetail, on the other hand, the strobilus lets the spores go and then falls apart. It doesn’t develop into something carrying a seed. And in gymnosperms, the cone develops into a seed-bearing structure, but the seeds are exposed to the environment (hence gymnosperm, “naked seed”), not enclosed as with a fruit.

I don’t really know offhand why ginkgos aren’t considered to have convergent fruit; I assume there’s some other developmental difference. I’m pretty sure there are other morphological factors (or ancestral morphologies) that unite flowers and differentiate them from cones and strobili too; the development of fruit was just the first I could think of.

4 Likes

I don’t know why, but my brain always mixes up Rhus and Rumex.

1 Like

It is peculiar that Ruscus, butcher’s broom, is a lily. But the only lily beetle I have was found on Ruscus and beetles don’t lie.

There are some rather unroselike plants in the Rosaceae, e.g. meadowsweet Filipendula ulmaria.

3 Likes

but - pine cones have their seeds enclosed in a very hard shell. Where does that fit in? It is not a botanical ‘nut’

the climber’s friend has teeth and floofy red flowers

That’s a good question; my understanding is that the cones always eventually open and expose the seeds, but then again, I only really know my local conifers! So I could be wrong about that in other areas.

Reading about it, it also seems cones develop from modified leaves or scales, whereas fruit develop from the ovule, so I suppose there’s also a developmental distinction.

In gymnosperms, the ovule is enclosed in structures (including the megasporangium) that have an opening for the sperm to go into. So the ovule is not entirely covered, so it’s naked. The hole is tiny and it closes over later. The megasporangium will be the food for the embryo when the seed germinates. In flowering plants, the ovary is completely closed and the pollen forces its way in by producing a small tube that grows into the stigma and down the style and finally into the ovule in the ovary. The two sperm are released into the megasporangium where one fertilizes the ovule (egg) and the other joins with two (or more) others to become endosperm, which will be the food for the embryo when the seed germinates.

A big advance of flowering plants is the timing of laying down food for the embryo. In gymnosperms, it happens, or at least starts, before fertilization, so that energy is wasted if fertilization doesn’t happen. In flowering plants, fertilization and the initiation of laying down food are simultaneous, so the probability of wasting the energy is lower.

5 Likes

Ooh that’s interesting! Thank you for the detailed explanation! I didn’t know about pollen growing a tube through the tissue down into the ovule, that’s really neat.

1 Like