Identifer Profile: @sedgesrock

This is the eighth in an ongoing monthly (or almost monthly) series profiling the amazing identifiers of iNaturalist! I've illustrated this post with photos from observations of African sedges that @sedgesrock has identified.

Sedges (Family Cyperaceae). They can be found pretty much all over the world, they’re easy to see and photograph, but they don’t get the kind of appreciation that many showy, colorful plants do. However, South African botanist Clare Archer (@sedgesrock) is, as you might expect, a fan of these organisms and she’s brought her love and knowledge about them (and other plants) to iNat! Sedges, says Clare, 

are such fun to study in the field and under the microscope, particularly the fruit where shape, and surface patterning is often species-specific. During my M.Sc. (on southern African Carex), I removed the outer cell walls of the fruit of several species, then studied the newly-exposed silica bodies under SEM. That was a wow moment, especially since I did not know what to expect!

Clare grew up in and around the city of Pietermaritzburg, South Africa, and tells me

I was interested in nature from an early age because we had a large garden that my mother filled with mainly indigenous plants. She knew the scientific name of every plant and naturally passed on that knowledge to me. The many birds and other creatures that arrived to enjoy the garden were observed with great excitement and identified whenever possible, and likewise family holidays were spent exploring the country and camping in wild places while observing and identifying wildlife.

Inspired by Jacques Cousteau, Clare originally wanted to go into marine biology but did not find animal dissection enjoyable so she ended up studying Geology. “During vacations I worked as an assistant for Prof. K.D. Gordon-Gray who mentored me and had a research interest in Cyperaceae.” 

After graduation, a vacancy in the monocot and fern wing (“everything except grasses”, she says) of the Botanical Research Institute’s Herbarium in Pretoria (now Tshwane) and she took it.

The work involved identification services, taxonomic and specimen curation and research. In later years there was the increasing responsibility of curating the specimen database. In between there was an M.Sc. after hours (Dissertation: “The genus Carex (Cyperaceae) in Southern Africa”). Following the M.Sc. project I began the full-scale taxonomic work on the Cyperaceae of Southern Africa (technically a Flora) that continued until early retirement [in 2015] due to deteriorating eyesight.

In 2018, Clare’s husband (@robertarcher397) showed her “this wonderful website” and helped her create an account on iNat. Since then she’s added identifications to nearly one hundred thousand observations, focusing mostly on plants in southern Africa, and is by far the top identifier of sedges on the African continent.  

Sedges are our friends! Many people regard them as weeds: in fact two species are “the world's worst weeds” because they are adapted to proliferate in irrigated, cultivated lands. However, [sedges] are found in nearly every habitat and especially in wetlands where their roots prevent soil erosion and improve water quality, and the aerial parts provide food and shelter for wetland birds and animals.

Clare also enjoys adding coarse IDs to observations which lack any ID, or in cases where she she can move the ID to a finer level, even if it’s not species. 

This is to help experts in their fields to find the observations that are relevant to them. I like to feel that I'm "rescuing" observations from relegation to "Unknown" when they are often perfectly identifiable…With the availability of expert IDs in other groups I have added to my knowledge of those groups, so while I have given time to do IDs I have also gained a great deal from iNat.

I try to check the new observations (for Southern Africa) at least once per day, just for personal enjoyment. It has re-awakened the sense of wonder in our natural world that I experienced as a child, but also preserves my long-accumulated knowledge of plants and their names.

(Photos (from top to bottom): Cyperus hystricoides by @robert_taylor, Ficinia radiata and Cyperus niveus var. leucocephalus both by @felix_riegel.)

- Check out sedge diversity and beauty on iNat! Here are the most-faved sedge observations.

- Clare tells me that pressed sedge specimens and microscopy are ideal for identification, but she has some tips on how to best photograph wild sedges for iNat. Photos should include, if possible:

1. Habitat (wetland, streamside, among rocks etc.)
2. Longevity & habit: show base of plant & its neighbours (indicating whether annual or perennial; a tussock or rhizomatous etc.)
3. Leaves & stem (leaf shape, hairiness, arrangement; stem scapose or nodose)
4. Mature inflorescence appearance (bracts, overall shape i.e. umbellate, paniculate, compact head etc.)
5. Close-up of individual inflorescence units (spikelet, head etc.)
6. Close-up of glumes
7. Close-up of fruit (if at all possible)

Posted on March 31, 2022 09:21 PM by tiwane