Poaceae
Tripsacum

Tripsacum laxum Nash

First published in N.L.Britton & al. (eds.), N. Amer. Fl. 17: 81 (1909)
This species is accepted
The native range of this species is Central & S. Mexico to Honduras. It is a perennial and grows primarily in the wet tropical biome. It is used as animal food and a medicine.

Descriptions

Morphology General Habit
Perennial. Butt sheaths pilose. Culms erect; robust; 300-500 cm long; 5-10 mm diam. Leaves cauline. Leaf-sheaths glabrous on surface. Ligule a ciliolate membrane. Leaf-blades 40-80 cm long; 30-70 mm wide. Leaf-blade surface glabrous. Leaf-blade apex acuminate.
Morphology Reproductive morphology Inflorescences
Monoecious; with male and female spikelets in the same inflorescence. Inflorescence composed of racemes; terminal and axillary. Peduncle glabrous. Racemes 12-23; digitate; drooping; arcuate; smoothly terete; unilateral; 10-20 cm long. Central inflorescence axis 4-10 cm long. Rhachis (female) fragile at the nodes; subcylindrical and excavated; 2-3 mm wide. Spikelet packing abaxial. Rhachis internodes oblong; 2-3 mm long; adherent to upper glume of sessile spikelet. Rhachis internode tip transverse; crateriform. Sexes segregated; on bisexual branches; with male above. Spikelets sunken; solitary. Fertile spikelets sessile. Male spikelets sessile and pedicelled; 2 in a cluster. Pedicels (male) 2.5-7 mm long.
Fertile
Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets ovate; dorsally compressed; 5 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus base truncate; with central peg; attached transversely.
Morphology Reproductive morphology Inflorescences Bracts Glume
Glumes dissimilar; reaching apex of florets; firmer than fertile lemma; shiny. Lower glume ovate; 1 length of spikelet; indurate; without keels. Lower glume apex acute. Upper glume ovate; cartilaginous; without keels. Upper glume apex acute.
Morphology Reproductive morphology Flowers Florets
Basal sterile florets barren; without significant palea. Lemma of lower sterile floret oblong; hyaline. Fertile florets female. Fertile lemma oblong; hyaline; without keel. Palea hyaline.
Morphology Reproductive morphology Inflorescences Spikelets
Male spikelets distinct from female; with free pedicels; all deciduous together; 4-6 mm long. Male spikelet glumes 2; membranous; muticous. Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets ovate; dorsally compressed; 5 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus base truncate; with central peg; attached transversely.
sex Male
Male spikelets distinct from female; with free pedicels; all deciduous together; 4-6 mm long. Male spikelet glumes 2; membranous; muticous.
Distribution
North America: Mexico. South America: Mesoamericana.
Reference
Andropogoneae. Fl Meso-Am 1995.
Diagnostic
Male internodes 0.3-0.5mm wide.
[GB]

Distribution
Biogeografic region: Andean. Elevation range: 500–1500 m a.s.l. Naturalised in Colombia. Colombian departments: Boyacá, Cundinamarca, Valle del Cauca.
Habit
Herb.
Conservation
IUCN Red List Assessment (2021): LC.
Ecology
Habitat according IUCN Habitats Classification: shrubland, artificial - terrestrial.
[UPFC]

Extinction risk predictions for the world's flowering plants to support their conservation (2024). Bachman, S.P., Brown, M.J.M., Leão, T.C.C., Lughadha, E.N., Walker, B.E. https://nph.onlinelibrary.wiley.com/doi/full/10.1111/nph.19592

Conservation
Predicted extinction risk: not threatened. Confidence: confident
[AERP]

IUCN Red List of Threatened Species https://www.iucnredlist.org/species/101340166/173973364

Conservation
LC - least concern
[IUCN]

The Useful Plants of Boyacá project

Morphology General Habit
Herb.
Ecology
Alt. 500 - 1500 m.
Distribution
Naturalised in Colombia.
Conservation
Not Evaluated.
[UPB]

Bernal, R., Gradstein, S.R. & Celis, M. (eds.). 2015. Catálogo de plantas y líquenes de Colombia. Instituto de Ciencias Naturales, Universidad Nacional de Colombia, Bogotá. http://catalogoplantasdecolombia.unal.edu.co

Distribution
Naturalizada en Colombia; Alt. 500 - 1500 m.; Andes.
Morphology General Habit
Hierba
Conservation
No Evaluada
[CPLC]

Uses

Use Animal Food
Used as animal food.
Use Gene Sources
Used as gene sources.
Use Medicines
Medical uses.
[UPFC]

Use Gene Sources
Crop wild relatives which may possess beneficial traits of value in breeding programmes (State of the World's Plants 2016).
[UPB]

Sources

  • Angiosperm Extinction Risk Predictions v1

    • Angiosperm Threat Predictions
    • http://creativecommons.org/licenses/by/4.0

  • Catálogo de Plantas y Líquenes de Colombia

    • http://creativecommons.org/licenses/by-nc-sa/3.0

  • GrassBase - The Online World Grass Flora

    • Clayton, W.D., Vorontsova, M.S., Harman, K.T. and Williamson, H. (2006 onwards). GrassBase - The Online World Grass Flora.
    • http://creativecommons.org/licenses/by-nc-sa/3.0

  • IUCN Categories

    • IUCN Red List of Threatened Species
    • http://creativecommons.org/licenses/by-nc-sa/3.0

  • Kew Backbone Distributions

    • The International Plant Names Index and World Checklist of Vascular Plants 2024. Published on the Internet at http://www.ipni.org and https://powo.science.kew.org/
    • © Copyright 2023 World Checklist of Vascular Plants. http://creativecommons.org/licenses/by/3.0

  • Kew Names and Taxonomic Backbone

    • The International Plant Names Index and World Checklist of Vascular Plants 2024. Published on the Internet at http://www.ipni.org and https://powo.science.kew.org/
    • © Copyright 2023 International Plant Names Index and World Checklist of Vascular Plants. http://creativecommons.org/licenses/by/3.0

  • Kew Science Photographs

    • Copyright applied to individual images

  • Useful Plants and Fungi of Colombia

    • http://creativecommons.org/licenses/by-nc-sa/3.0

  • Useful Plants of Boyacá Project

    • ColPlantA database
    • http://creativecommons.org/licenses/by-nc-sa/3.0