Cypress Spurge prefers dry and warm habitats. In the Donau-Auen National Park, the plant may be spotted along the Marchfeldschutzdamm (Marchfeld protective barrier). This dyke is an important refuge for meadow flora and fauna of the Marchfeld area.
Cypress Spurge is a perennial plant growing to 15-30cm (max. 50) which contains a milky sap. Typical flowering specimens have linear, needle-like leaves from 1-3cm long and 3mm wide. The alternate leaves which look like fir needles (or as some say, cactus spikes) along with the inflorescence typical of the genus are the best keys to identification. On thin stems, the flowers umbels are embraced by yellow-green bracts which later turn red to fiery red. The blossoms smell strongly of honey. Sterile lateral buds are significantly narrower and covered in brush-like growth. In addition to these more common plants, stemless individuals with short stout leaves may also be found. These have been infected with a rust fungus, are weirdly misshapen and do not flower.
The species may be found throughout most of Europe, parts of Asia and northern and eastern Africa. In Austria, Cypress Spurge may be found frequently in all provinces, from lower elevations all the way to montane zones. The plant may be spotted on the edges of paths, dykes, warm arid woodland margins and dry grasslands. In the Donau-Auen National Park Cypress Spurge is ubiquitous along the Marchfeld protective barrier and frequent in the xeric habitats of the Lobau.
Endangerment and Conservation Status
The species is not endangered.
Cypress Spurge reproduces primarily by vegetative means through its well-developed rhizomes. In autumn, renewal buds for the next season are developed at the base of each shoot. In the months of April and May cyanthia appear, formed of otherwise unspectacular individual male and female flowers. Each cyanthium consists of a female flower without a perianth surrounded by a group of five male flowers. The male flowers are also reduced and consist of a single stamen. The surrounding yellow to reddish-coloured bracts ensure visual appeal for insects. To be more visible, many of these cyanthia are gathered together in an umbel-like flowerhead. The explanation for this very eccentric flowering form can be found in the history of the Euphorbia genus and is quite complicated. Originally, these plants were pollinated by insects but later turned anemophilous, e.g. pollinated through dispersal by wind, in the course of evolution. For this purpose, the perianths (which are not necessary in wind dispersal) were reduced, as were the flowers, which were thus separated into male and female. Only a sole stamen remained on the male flower; the female flowers were reduced to an ovary with style and stigma. Later, the anemophilous form once again became entomophilous, or pollinated by insects. And because only extremely reduced monoecious solitary flowers were available, they were grouped in such a way as to form a functional hermaphrodite. Visual appeal was provided through brilliantly coloured bracts, since the actual perianth had degenerated during its anemophilous era.
All native Cypress Spurge types are extremely toxic. When broken, the plant emits a milky sap which is said to cure warts. The sap can lead to blindness if it gets into the eyes. The sap functions first and foremost as a shield against plant-eating insects and grazing animals. However, the so-called Spurge Hawk-moth (Celerio euphorbiae) has managed to break through this chemical barrier. Its colourful caterpillars dine solely on Cypress Spurge plants, even using the plant's poison to make themselves inedible to their predators.