The majority of the tourists who visit Greece is drawn there by the crystalline waters of the seas and the splendid vestiges of its ancient culture, and probably know little about the variety and the abundance of the flora of this country, which counts an astonishing number of species-more than 6,000-plus subspecies and varieties. In proportion to its size, Greece has more species of flowers than does any other European country or the United States. The plenteousness of Hellenic flora is the result of a number of factors, first among which the particular geographical position of the country. Together with Greece's climatic conditions, it permitted the land to receive contributions from other nearby floras, above all those of central Europe and Anatolia.
Following the lowering of the level of the sea, relics of the flora of the Tertiary period that survived the glaciations of the Quaternary succeeded in gradually migrating from their areas of origin over the bridge that the glaciers had created and that united different lands. Before the last inundation of the Mediterranean Sea, species of eastern origin had reached Europe through Thrace and other areas of the central and southern Aegean regions. That the flora of Greece and of the Balkan area in general evolved from the ancient Paleozoic flora is confirmed by the presence of numerous endemic or paleo-endemic species now found only in small colonies. Examples include some species that came from the Balkans and Asia Minor, like Ebenus cretica, whose center of distribution is localized in Asia, or Jancaea heldreichii, a member of the family Gesneriaceae endemic to Mount Olympus and of a genus that groups almost exclusively tropical and subtropical plants.
Elements originating in Africa, the Caucasus region, and the northern Balkan peninsula but which did not spread to the western regions of Europe became established in Greece following the disappearance of the primigenial forests, which gave way to arid soils favorable to the growth of xerophytic Mediterranean plants.
These factors established Greece became a crossroads in the migrations of different floras, a sort of botanical refugee center in which many species native to central Europe (including many Alpine species) as wail as Mediterranean, Balkan. Near Eastern and Northern African species all settled and spread.
Another important aid peculiar fact about Greek flora is that it counts an extremely high number of endemic species about 800. Some of these are relics of ancient Tertiary flora which in other places was destroyed by the glaciations but found suitable conditions for survival in Greece; nevertheless, these archaic forms alone are not sufficient to explain the high endemism, since many of the species certainly belong to more recent geological eras and many of which originated in the places in which they were first identified.
The changes in the level and the surface area of the Mediterranean Sea resulted in the fragmentation of a great number of land masses, mountain chains, and islands, and many animal and plant species were consequently isolated at one time or another during geological history. These conditions created new habitats populated by species and subspecies typical of these environments and thus favored the evolution of extremely diversified local populations which, despite their common origin, progressively diverged the ones from the others, specialized, and gave rise to a many new endemic species. These species-which often create problems of classification, as do the many species and subspecies now evolving and not yet well defined genetically, with hybrids and local varieties that are sometimes difficult to distinguish - justify the conclusion that on Greece the factors that contributed to creating new species operated more actively than in any other European country.
We must also consider the fact that in the last 5, 000 years Hellenic flora has received a further evolutionary boost from anthropic impact. In the period of their maximum splendor, the ancient civilizations that arose on Crete and then in the rest of Greece in about the second millennium BC-of which today we admire the splendid remains of art and culture-counted more than a million inhabitants who lived off the natural environment, exploiting it and inevitably modifying its original characteristics. Extensive forested areas were razed to obtain the wood needed for use as fuel or construction material; once deforested, the land was burned to make it suitable for use for grazing or farming and was later abandoned when it was worked out.
Since very ancient times, therefore, the activities of man have modified the composition of the habitats, shifting the original state of equilibrium and organization -the so-called "climax state"- toward degraded forms. Over the course of history, as the human population grew the available natural resources progressively decreased and at the same time a new type of vegetation appeared. It is composed of resistant, frugal species with scarce nutritional requirements, which until becoming dominant had always been subordinate to other types of vegetation. The maquis, the garrigue, and the phrygana are examples of the new vegetation formations that took the place of the original forest mantle, as new are commensal species that cohabit with crops. Other species yet were imported and adapted perfectly to the local climate, like the Indian prickly pear and the American agave, so that over the centuries a great number of exotic plants began to grow alongside the autochthonous species, widening the variety of Greek flora but also reducing the number of original habitats.
The evolution of flora in Greece was thus greatly influenced by man, the unknowing cause of the survival and diffusion of many species that flower in uncultivated land and the cultivated fields, among which species introduced as ornamentals or crops that became acclimatized in loco and now are a stable and integral part of the contemporary flora of the region.
Nevertheless, if on the one hand deforestation caused irreparable damage to the original climax communities, on the other it contributed to creating local micro-climates in which graze-resistant herbaceous species, including many neo-endemics, became acclimatized. The work of man has undoubtedly catalyzed evolutionary changes, stimulating the rise of new species with characteristics of greater variability, but it remains difficult to establish the importance of these recent transformations in relation to the broad immensely broad scale of geological time.
This guide describes the most common and at the same time most important flowers that botany enthusiasts may observe during their holiday stays in Greece. To facilitate species recognition, the plants have been grouped by distribution areas: coastal habitats (sandy and rocky), phrygana and garrigue, maquis, woodlands, rupestrian habitats, wetlands, gorges, and anthropized environments (roadsides, old walls, cultivated land, abandoned fields); a separate chapter is dedicated to the naturalized exotic plants that are by now a common feature in the Greek landscape.
Obviously, many plants are common to more than one environment; this is especially true for the phrygana -in which many of the plants listed in the section on the garrigue are also found- and for the gorges, composite environments in which we find the plants that typically live on cliffs and along watercourses in many other areas. For easier identification of similar plants distributed in different areas, we suggest consulting the appendix for a complete list of all the plants illustrated and described and a glossary of the technical terms used in the text. Each species is listed by its scientific name, which is composed of the capitalized genus name, the species name, and the abbreviated name of the author who first described each. The family to which each species belongs is given in parentheses.
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