Task 3

Working with plants

My cohort and I were asked to complete a diagnostic table of UK plant families prior to a laboratory session. I then attended this session on 02 October 2023, given by Dr Matthew Bulbert (Senior Lecturer in Conservation Ecology) and Dr Andrew Lack (Senior Lecturer in Environmental Biology) where I used this table and other diagnostic tools to identify plant specimens, before proceeding to dissect and investigate plant structure.

The second part of this task was to complete a ‘scavenger hunt’.

Diagnostic table for UK plant families

For this part of the task we were asked to complete a blank diagnostic table of UK plant families with characters that could be used for identification. Specifically, I was assigned the families Ranunculaceae and Orobanchaceae.

I found this task difficult as there was no single source of information that listed all the characters required for this table. Additionally, due to time/geographical constraints, I was unable to access many print books for this task. Some sources of information offered if not contradictory, slightly confusing descriptions e.g. for Orobanchaceae Stace (2010, p680) states “opposite or alternate sessile or petiolate leaves” yet Simpson (2010b) states “leaves are simple, spiral or opposite” which caused me to spend a considerable amount of time trying to determine what the characters were!

An additional confusion on my part seems may have stemmed from the fact that Orobanchaceae was formerly in the Scrophulariaceae family.

The rows that I completed can be seen below:

The more related a species is to another, in terms of evolution and phylogenetic trees, the more likely they are to share common characteristics. This should be no surprise as if they share a common ancestor then it is likely that traits from this ancestor will be present in both species i.e. it is likely that species in the same family will share more characteristics with one another than with species across the other families.

That being said, the same or similar characteristics can evolve independently in different branches of a phylogenetic tree, so just because a characteristic is shared it does not necessarily mean that species are closely related. This means care must be taken and to not assume a shared characteristic is always indicative of close evolutionary relatedness but it may often be a good starting point for identification.

Identification to family

Using the table, along with a paper key (Streeter et al., 2016) I attempted to identify some of the specimens. Below are the images and my contemporaneous notes. I have emboldened characters I feel were important for the identification and have added some additional notes to things I missed. I’ve listed below in chronological order the specimens I attempted.

Specimen 8

• Leaves alternate, serrated edges

• Flowers composite

Asteraceae (Composite)

Specimen 5

• Leaves alternate, serrated edges

• Flowers composite

Asteraceae (Composite)

Specimen 7

• Leaves opposite, serrated edges, veins branched

• Flower stalks whorled

• Stem square

• Inflorescence (flowers at the end above the stem)

Lamiaceae (Mint)

Specimen 2

• Basal leaves

• Parallel veins

• Flower arrangement: inflorescence

• Stem angular - edges

Cyperaceae (Sedge)

Specimen 16

• Leaves opposite, wavy edges

• Flower stalks whorled

• Stem square

• 2 petals? Inflorescence

Lamiaceae (Mint)

Specimen 19

• Flowers composite

• Leaves whorled, veins branched

Asteraceae (Composite)

Specimen 17 and 23

Specimen 23 had more flowers that were easier to see

• Opposite leaves, compound? Veins branched

• Flowers radial, 5 petals free, 5 sepals free

Geraniaceae (Geranium)

Specimen 24

• Leaves alternate, serrated, veins branched

• Flower composite

Asteraceae (Daisy)

Specimen 25

• Basal leaves, leaves alternate, simple

• Flowers 4 petals, radial?

• Inflorescence: rasceme?

• -important character not noted when ID-ing, 6 stamens, 4 tall 2 short

Brassicaceae (Crucifers/cress, previously Cruciferae)

Specimen 26

• Leaves whorled, veins branched, serrated? - leaves actually pairs of opposite leaves

• Flowers whorled, bilateral

• Stem square

Lamiaceae (Labiates) dead nettle

Specimen 10

• Leaves alternate, veins parallel, basal sheaf

• Angular, 3 sides

• Flower ends in inflorescence

Cyperaceae (Sedge)

Specimen 11

• Leaves alternate, veins parallel, basal sheaf

• Stems round, hollow

Poaceae (Grasses, formerly Gramineae)

Specimen 12

• Stem solid, round, full

Juncaceae (Rushes)

Flower dissection

As an introduction to this I learnt that about 80% of flowering plants are hermaphrodite, approx. 10-15% are dioecious (with male and female flowers on separate plants) and 5% are monoecious (with male and female flowers on the same plant).

For this exercise we dissected and considered the main structures of sepals, petals, stamens and carpels on 3 flowers: Lisianthus, Lily and Chrysanthemum. In order to view the features initially I dissected the flower to give a cross-sectioned view. For the composite flower I cut off the ray floret and disc floret to investigate these flowers separately.

Lisianthus

Lily

Chryshanthemum

Plant scavenger hunt

References

Simpson, M. G. (2010a) '8 - Diversity and Classification of Flowering Plants: Eudicots', Plant Systematics. 2nd edn. San Diego: Academic Press, pp. 275-448.

Simpson, M. G. (2010b) Diversity and Classification of Flowering Plants: Eudicots: Orobanchaceae. Available at: https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/orobanchaceae (Accessed: 02 November 2023).

Stace, C. A., Thompson, H. and Stace, M. (2019) New flora of the British Isles. Fourth edition. Suffolk: C & M Floristics.

Streeter, D., Hart-Davies, C., Hardcastle, A., Cole, F. and Harper, L. (2016) Collins wild flower guide. Revised and updated 2nd edition. London: William Collins.

Strong, M. T. (2021) 'Guide to the genera of Lianas and climbing plants in the neotropics', Available at: https://naturalhistory.si.edu/sites/default/files/media/file/orobanchaceae.pdf (Accessed: 02 November 2023).

Sutherland, W. J. (2006) Ecological census techniques : a handbook. 2nd edn. Cambridge, UK: Cambridge University Press.

Tilling, S. (2014) A key to the major groups of British terrestrial invertebrates. Second edition. Telford: FSC.

Wetherwax, M. (2017) 'Orobanchaceae', Jepson eFlora(Revision 5), Available at: https://ucjeps.berkeley.edu/eflora/eflora_display.php?tid=210 (Accessed 02 November 2023).

Wu, Z. Y., P. H. Raven & D. Y. Hong (2001) 'Ranunculaceae', Flora of China. Beijing and St.Louis: Science Press and Missouri Botanical Garden Press. Available at: http://flora.huh.harvard.edu/china/mss/volume06/Ranunculaceae.pdf (Accessed: 02 November 2023).

Botany Library Ranunculaceae: Characters and Affinity. Available at: https://www.botanylibrary.com/dicotyledons/ranunculaceae-characters-and-affinity-dicotyledons-botany/15023 (Accessed: 02 November 2023).

Clarke, I. and Lee, H. (2019) Name That Flower: the Identification of Flowering Plants: 3rd Edition. Melbourne, Australia: Melbourne University Publishing.

Craig C. Freeman, R. K. R., Wayne J. Elisens (2020) 'Flora of North America',  Available at: http://floranorthamerica.org/Orobanchaceae (Accessed: 02 November 2023).

Henderson, P. A. (2016) Ecological Methods. Newark: John Wiley & Sons, Incorporated. New York Academy of Sciences Ser.

Poland, J. and Clement, E. J. (2020) The vegetative key to the British flora : a new approach to naming British & Irish vascular plants based on vegetative characters. Second edition. Southampton [England]: John Poland.

Reed College Orobanchaceae. Available at: https://www.reed.edu/biology/courses/bio332/PlantFamily/family_info/Orobanchaceae.html (Accessed: 02 November 2023).

Roayl Botanical Gardens Kew Orobanchaceae. Available at: https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:30003446-2/general-information (Accessed: 02 November 2023).

Royal Botanical Gardens Kew Ranunculaceae. Available at: https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:30000277-2 (Accessed: 02 November 2023).

Salim, M. A., Mohamed, A.-S. H. and Tantawy, M. E. (2016) 'Morphological study of some taxa of Ranunculaceae Juss in Egypt (anatomy and pollen grains)', Beni-Suef University Journal of Basic and Applied Sciences, 5(4), pp. 310-319. Available at: https://doi.org/https://doi.org/10.1016/j.bjbas.2016.10.002.