These pages provide general information about Opuntia. Each page is aligned to a different topic such as references used in this Website, Website policies, or DNA/chromomes, etc.

General Opuntia Topics

Opuntia topics Opuntias are a vast and varied group. They grow on every continent except Antarctica. Prickly pears interact with animals and are used as animal fodder; are affected by the weather; are eaten for food, vitamins and overall health; and even provide a red dye. These articles will help you find out more about …

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Who we are Our website address is: https://www.opuntiads/*. Read about us at the About page.  What Data We Collect and Why We Collect It Comments Comments may be made at the bottom of pages or by email. We do not collect personal data nor personally identifying information unless you provide your email address for comments …

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Opuntia Biology

Biology is Important Reproduction, DNA biology, and ecology are powerful drivers of Opuntia biology. Knowledge of these topics will help us understand opuntias. The genetics, biology, and speciation of Opuntia are poorly understood. In fact, opuntias remain a poorly studied group overall except for O. ficus-indica. This latter species is much studied. However, most of …

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Opuntia References

Introduction Multiple references were consulted during the construction of this prickly pear website–Opuntia Web. There are countless confusing references about cacti in general and opuntias in particular; there are often many names that refer to the same species of cactus. We worked our way through them to decide Opuntia names. Generally, we chose names that …

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Opuntia DNA

Opuntia DNA and Ploidy An index to published chromosome information many cacti and prickly pears is at: Index to Plant Chromosome Numbers (IPCN, Tropicos). Another index to many plants is at: Chromosome Counts Database, Rice et al., 2016, Website.  Ploidy information for many Opuntia species of the USA may also be found in “Pricklypears Commonly Found in the United …

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Opuntia Artist: LCC Krieger

Introduction Louis Charles Christopher Krieger (1873-1940)  worked with David Griffiths at the Plant Introduction Garden in Chico, California. Griffiths was interested in the forage potential of prickly pear cacti (Opuntia spp.).  Details Krieger painted a large series of species and forms of Opuntia between 1912 and 1917 for Griffith’s studies. These paintings are in the collection of …

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Opuntia Artist: Mary Emily Eaton

Introduction Mary Emily Eaton (1873-1961) was born on 27 November 1873 in Coleford, Gloucestershire, England.  She  is best known as a botanical artist for her illustrations in The Cactaceae (Britton and Rose, 1919-1923) for which she was the principal illustrator. Details She was employed by the New York Botanical Garden from about 1911 to 1932. Her illustrations are housed at the …

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How Opuntia Species Are Identified

Introduction The first iteration of Opuntia Web was built in 2005. Our scientists identified Opuntia species in the field. We visited the western states to study cacti in habitat. We also visited Florida, the southern Atlantic states, and the Midwest to observe cacti in those regions (e.g., O. macrarthra). We made a visit to Pennsylvania to verify the presence of O.

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Checklist of differences between O. lindheimeri and O. engelmannii

Introduction Opuntia engelmannii and O. lindheimeri, are similar prickly pears, but there are also constant differences between these prickly pear cacti. We accept these opuntias as separate and distinct species. However, O. lindheimeri has been described as a variety of O. engelmannii by some authors. However you think of them (one Opuntia species or two), …

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Introduction We are a group of botanists that enjoys writing about and photographing Opuntia and related plants. We enjoy studying them in the field and growing them in our gardens. We hope you enjoy reading about them.  Write to us. We are always happy to hear from others if there is a point we have not …

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