Introduction to Euphorbia segetalis: Identification and relevance
Euphorbia segetalis, Also known as tabaibilla o field milkweed, is a species of plant belonging to the family Euphorbiaceae, widely distributed in Mediterranean regions, including cultivated fields, anthropized areas and stony soils. It is notable for its ecological versatility, its resistance and its variable life cycle, as it can be grown as an annual, biennial, or perennial plant. It is valued for both its botanical interest and its ecological role, and is important for those looking to expand their garden with native species or those with low water requirements.
This species is used as a reference for the biodiversity of Mediterranean agroecosystems, highlighting the natural balance between agriculture and wild flora. Furthermore, due to the morphology of its seeds and the uniqueness of its latex, Euphorbia segetalis It is the subject of study in various scientific fields.
Taxonomy and nomenclature
- Domain: eukarya
- Supergroup: Archaeplastida
- Phylum: Chloroplastida
- Division: Streptophyta
- Subdivision: Spermatophytina
- Class: Magnoliopside
- Order: Euphorbiales
- Family: Euphorbiaceae
- Gender: euphorbia
- Species: Euphorbia segetalis
Etymology of Euphorbia: The name derives from the Greek euphorbion and Latin euphorbea, referring to the characteristic latex and to a Greek physician, Euphorbus, noted for his studies at the court of King Juba II of Mauritania.
Etymology of segetalis: From Latin segetalis, which means 'that grows among cereals', in clear allusion to its common presence in wheat fields and crops.
Synonyms: Euphorbia linifolia, Euphorbia longibracteata, Euphorbia pinea, Tithymalus leptophyllus, Tithymalus segetalis.
Morphological description of Euphorbia segetalis
Presentation of the plant: Euphorbia segetalis is a glabrous or glabrescent plant, with glaucous green hues and a height that varies from a few centimeters to 100 cm in optimal conditions, although it is generally between 40 and 80 cm. It usually has straight stems, simple or well branched from the base (3 to 20 fertile branches), with a reddish at the base of the stem.
Sheets: The average leaves measure between 27 and 40 mm long by 2 to 4 mm wide. They are linear, lanceolate or oblong; sometimes oblanceolate. The leaves have an entire margin, are acute or obtuse and mucronate, arranged loosely or densely, and the lower ones tend to be expire early.
Inflorescence: It has pleochrosite-like inflorescences (multiple branches at the top), with 4 to 8 rays up to 70 mm long. The rays are usually forked several times; the lower ones are glabrous, while the upper ones may be hairy. The bracts vary from ovate-lanceolate to semicircular, with free margins and frequently blunt tips.
Cyatio: The cyathium is a typical inflorescence of the genus, measuring 1,3 to 1,7 mm and displaying yellowish-green nectaries, with two corniculate appendages measuring 0,3 to 1 mm. Occasionally, additional shorter appendages are present.
Fruit and seeds: The fruit, a capsule (tricoca), is subspherical, 2,8–3,4 mm long by 3–3,5 mm wide, markedly sulcate and depressed. The grayish seeds, 2–2,3 mm long by 1,3–1,5 mm wide, are subovoid, with a reticulated surface and a conical, subsessile caruncle.
Flowering and vegetative period
Euphorbia segetalis It displays extensive flowering, which generally occurs from March to October. Most of the blooming occurs in spring, although specimens can be found in bloom almost year-round, depending on the climatic conditions of the area.
Habitat and distribution
Natural habitat: Euphorbia segetalis thrives in ruderal sites, cultivated fields, stony pastures, maritime rocky areas, and human-infested areas. It is a species with low substrate demands, tolerating soils ranging from calcareous to basically poor.
Altitudinal range: It is found from sea level to 1200-1400 meters above sea level.
Geographical distribution: Native to regions of southern Europe, North Africa (especially Morocco), Macaronesia (the Azores, Madeira, and the Canary Islands), and present throughout much of the Mediterranean basin. It has also become naturalized in Australia, Madagascar, and eastern North America.
Scope in Spain and the Canary Islands: It is common throughout most of the Iberian Peninsula, especially in areas with a Mediterranean climate and the Canary Islands, where different varieties of the species are found, such as Euphorbia segetalis var. pinea.
Ecological and phytosociological behavior
Plant community: It is a weed species characteristic of class communities Stellarietea mediae. It shares its habitat with other nitrogenophilic plants such as Ajuga chamaepitys, Matricaria recutita y Capsella bursa-pastoris.
Adaptability: Shows great tolerance to moderate drought and sun exposure, although it can also grow in semi-shade. It does not tolerate saline or excessively fertile soils.
Ecological indicators according to Ellenberg:
- Light: It prefers sunny exposures, although it tolerates some shade.
- Salinity: It does not tolerate brackish soils.
- Humidity: Indicator of dry to moderately arid soils.
- Acidity: It grows well in soils with a pH of 5,5 to 8, with a slight preference for alkaline soils.
- Nitrogen: It predominates in moderately poor or barely enriched substrates; its presence decreases in highly fertilized soils.
Mode of dispersion and reproduction
Seed dispersal: The main route of dispersion is the myrmecochoria (transported by ants), although it can also be dispersed by human action through the movement of the soil, or to a lesser extent by wind. The seeds have a caruncle, which makes them easy for ants to collect for food, facilitating the spread of the species.
Height and seeds: The plant can grow up to 0,29 meters tall, and the seeds weigh approximately 3,0 mg. These dimensions contribute to its success in open and disturbed habitats.
Requirements and care of Euphorbia segetalis
Location: It requires sunny areas, although it tolerates semi-shade. It is especially suitable for xeriscaped or low-maintenance gardens where sun exposure is prolonged.
Recommended substrate: Imitate the natural habitat of this plant by using a substrate with excellent drainageA suitable mix might contain two parts black soil, one part solid humus, three-quarters coarse sand, half a part vermiculite, half a part perlite, and half a part charcoal. This recipe allows the roots of Euphorbia segetalis to develop in conditions similar to their natural environment, preventing waterlogging and promoting healthy growth.
Irrigation: Euphorbia segetalis is drought-tolerant and appreciates spaced-out watering. Be sure to let the top layer of the soil dry between waterings, avoiding excess moisture, which can cause root rot. In Mediterranean climates, occasional watering during the driest periods is sufficient. In pots, monitor drainage and avoid stagnant water.
Temperature: It tolerates both intense heat and low temperatures, although it cannot withstand severe frost or prolonged periods below freezing. It is ideal for growing in temperate climates or protected from frost in colder regions.
Nutrients: It doesn't require frequent fertilization. A light organic fertilizer at the beginning of the growing season can promote flowering and the development of fertile branches.
Pruning: It is not necessary for the plant's survival, but it can be done to remove dead branches or control its growth in the garden.
Multiplication: It reproduces easily by seed, although under favorable conditions it can successfully self-sow year after year.
Common problems, pests and diseases
Toxicity: Like most species of Euphorbia, Euphorbia segetalis Contains a milky latex that can be toxic or irritating upon contact with skin or mucous membranes. Avoid direct contact and wear gloves when handling it, especially if you're pruning or transplanting.
Pests: It is naturally resistant, but can occasionally be affected by aphids, mealybugs or, in the Canary Islands, the caterpillar of Hyles euphorbiaeThis moth may feed on the plant, although it rarely causes severe damage.
Diseases: The main root diseases are those caused by excess moisture, causing root rot. Good drainage is key to avoiding this type of problem. In humid environments, watch for the appearance of fungus.
Recommended treatments: In case of pests, ecological treatment with potassium soap or vegetable oils are usually effective. Avoid using harsh pesticides that could harm the biodiversity of the environment.
Traditional uses and ecological value
Ecological value: Euphorbia segetalis plays an important role as a refuge and food source for insects and other soil organisms. It also contributes to the restoration of degraded soils and the biodiversity of agricultural and natural landscapes.
Traditional uses: Although it is not widely used in medicine or cooking due to its toxicity, in certain regions it has been used anecdotally as an ornamental plant or part of wild arrangements.
Symbolism and culture: The genus Euphorbia is associated with the resilience y adaptability in difficult environments, values that have made it stand out in local ethnobotany.
Comparison and similar species
Species with which it can be confused: It is important not to confuse Euphorbia segetalis with Euphorbia medicaginea, as they share habitats and morphology. The key difference lies in the seed ornamentation, which is furrowed in E. segetalis and wrinkled in E. medicaginea.
The variety is also found in the Canary Islands Euphorbia segetalis var. pineapple, which shares many morphological characteristics but presents adaptations to island conditions.
Gardening and propagation tips
Choosing the substrate and pot: Use containers with drainage holes and light substrates. Add gravel or volcanic rock to the bottom of the pot if growing in a container to optimize drainage.
Plant Association: Euphorbia segetalis can be grown alongside other succulents or xerophytic plants, such as Sedum, echeveria o Aloe, creating resilient, low-maintenance arrangements.
Reproduction by seeds: Sow the seeds superficially on the prepared substrate and keep them moist until germination, avoiding waterlogging.
Indicators of disturbance and resilience to grazing and tillage
Mowing frequency: It tolerates agricultural cutting or mowing cycles well, and can sprout again thanks to its protected seeds or buds.
Herbivory pressure: It withstands moderate grazing, competing effectively in mixed pastures and fields with livestock pressure.
Soil disturbance: Euphorbia segetalis can withstand some soil disturbance, such as plowing or surface tilling, making it suitable for agricultural areas and roadsides.
Biology and life type
Biological type: Its diverse life cycle allows it to be classified as both a hemicryptophyte (plants with buds close to the soil surface) and a therophyte (annual that survives seasonally in the form of seeds). For more information on its biology, visit the plant of life.
This adaptability gives you great ecological success in changing and disturbed environments.
Photographs and visual resources of Euphorbia segetalis
Below are several representative images to facilitate identification and appreciation of its morphological characteristics. See the full gallery for more details:
Additional resources and scientific references
- Castroviejo, S. et al., «Flora iberica. Vol. VIII. Haloragaceae-Euphorbiaceae.» CSIC.
- Midolo, G. et al., “Disturbance indicator values for European plants”, Global Ecology and Biogeography.
- Tichý, L. et al., “Ellenberg-type indicator values for European vascular plant species,” Journal of Vegetation Science.
- Chytrý, M. et al., “EUNIS Habitat Classification: expert system, characteristic species combinations and distribution maps of European habitats,” Applied Vegetation Science.
- Lososová, Z. et al., “Seed dispersal distance classes and dispersal modes for the European flora”, Global Ecology and Biogeography.
- Dřevojan, P. et al., “Life forms.”
Frequently asked questions about Euphorbia segetalis
- Is Euphorbia segetalis a poisonous plant?
Yes, it contains an irritating and potentially toxic latex, which is especially dangerous in contact with mucous membranes or wounds. - Can it be grown in a pot?
Perfectly, as long as very well-drained substrate is used and it is placed in a sunny spot. - What problems can it cause in gardens?
Although it is not an aggressive invasive plant, it can spread by self-seeding in bare or lightly covered soils. - How to distinguish it from other Euphorbias?
Due to the ornamentation of its seeds and the shape of its inflorescences; if in doubt, consult the specialized bibliography.
La Euphorbia segetalis It represents an excellent example of plant adaptation and resilience, ideal for those who want to incorporate hardy, low-maintenance native species into their green spaces. Its long-lasting flowering period, tolerance to diverse environmental conditions, and minimal maintenance requirements make it an ally for both sustainable gardening and local biodiversity. Its presence adds ecological value, discreet beauty, and an opportunity to discover the incredible adaptability of Mediterranean and Atlantic flora.
