Xanthosoma violaceum is a member of Araceae (Dastar Kachu in Bengali). It has fleshy leaves. How should I prepare a herbarium sheet for it, like how should I dry the sample, what is the standard technique for pressing this plant or similar kind of fleshy plant for e.g. Aloe vera, Bryphyllum pinnatum etc. Thanks in advance.
I warmly recommend the following booklet, downloadable for free (https://www.sanbi.org)
Victor, J.E., Koekemoer, M., Fish, L., Smithies, S.J., & Mössmer, M. 2004.
Herbarium essentials: the southern African herbarium user manual.
Southern African Botanical Diversity Network Report No. 25.
SABONET, Pretoria.
For fleshy cacti and ferns, you need a very thin cross section of the stem node and internode, also of the rhizome, a thin slice along the stem epidermis flattened as thin as possible, information on the arrangement of the spines (you'd want the leaf whorl pattern, any hairs, type of edge for leaves (ie: tooth patterns), branching patterns at maturity and if possible some sample of that that is hopefully not too thick for the sheet. For ferns type of spore packets and spore characters, vein patterns etc.), tap root or diffuse root, presence of enlarged rhizomes, information on the stomates including which side or sides of the leaf they are on. Scotch tape and a glass slide and microscope are useful for looking at stomate patterns. The shape of leaf tips diplayed or at least discribed. Look at what characters are important for keying out the family, genus and species. Some people divide leaves and have more than one sheet for the same leaf. Some fold them across newspaper and blotters while drying them, and only glue some of it to the sheet leaving the rest attached and folded, or do both. Any reproductive structures should be shown and/or described as they appear on the plant and put into packets. Show some of the front and back of each leaf, bract, flower petal, etc. You may have to dissect slices from the fruit and flowers in more than one direction. Pollen samples help too if present. Put extra material in a packet so people can look at it without destroying what's glued down. On the label, describe what you can of color, shape before flattening, surface structures including glands as well as hairs or the lack of them, what grows nearbye as best you can, soil and drainage patterns, what you know of rainfall patterns, ecosytem type, etc. Here are some characters of importance for seperating the Araceae from each other but look at local keys too: https://www.botanylibrary.com/angiosperms-2/monocotyledons/araceae-characters-and-distribution-monocotyledons-botany/15221
A very large plant can be divided into parts in order to make herbarium sheet. The parts of the plant also can be keep in separate pockets.
Secondly succulent plants are first boiled in Salt or normal water to make all tissue dry, then easily preserved.
I have not heard of boiling tissue as that will also change it structurally. It may be a good idea for some of the material, you could test that on material that is not particularly valuable, and also see how it reconstitutes for later dissection. Note: only taxonomists doing complete revisions should be dissecting any material from any herbarium sheet. However, very thin sections of the fleshy part(s), plenty of blotter material, and allowing for extra drying time, are in order.
Special category of plants required special treatment making, preparing good herbarium specimens. Consults few relevant literature example...Jain, SK & Rao, RR.1977.A field and herbarium techniques, Todays & Tomorrow's publication.
regards
Tall thin specimen can be dried making in V shape, N shape or W shape, and same shape paste on herbarium sheets. The succulent specimen can be dried by two horizontal pieces, inner surface and outer surface or Undersurface and upper surface.
The specimen required ling time and need to change newspaper and blatting paper many time.
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