The flora of Poland in the 20th century has been listed in full in only three publications. The first was a key, Rośliny polskie published in 1924, by three outstanding Polish botanists: SZAFER, KULCZYŃSKI and PAWŁOWSKI. Earlier, in 1919, the first volume of a work entitled Flora polska appeared, edited by RACIBORSKI. This work continued for many decades (1919–1980), with different editors and different authors for particular taxonomic units. In 1953 the second edition of the key, Rośliny polskie (SZAFER, KULCZYŃSKI & PAWŁOWSKI 1953) came out, revised and supplemented. This book was reprinted many times in later years but the contents were not changed. Only the third of these publications cover the area within the present Polish borders. The first edition of Rośliny polskie (SZAFER, KULCZYŃSKI & PAWŁOWSKI 1924) covered the territory of the Second Republic of Poland within the borders it had in 1921–1939, while Flora polska (1919–1980) covered the area of Poland within its borders from before the partitions. In the years 1985–1993 three volumes of new edition of the Flora Polski (Flora of Poland) have been published (editor A. JASIEWICZ). They are limited to the contemporary borders of Poland, but cover only several families of the choripetalous vascular plants. Thus none of the above works is adequate as a species checklist for the present territory of Poland. The nomenclature used in these works has also lost much of its currency.

Present checklist covers the whole of the vascular flora of Poland. It includes all native species and established alien species, as well as ephemerophytes (mainly according to ROSTAŃSKI and SOWA 1986–1987) and species often cultivated in Poland. Not included were sporadic fugitives from cultivated areas. These would have extended too much the checklist and made it less clear. The array of plants grown in home gardens has fundamentally changed in recent years. The cultivated species included in the checklist are the authors' choice of the taxa which most often occur in Poland.

TAXONOMIC DEFINITIONS

Species are defined narrowly in order to register the maximum number of taxa which can be distinguished in an unambiguous way. In practice this means that in almost all cases of discrepancies with respect to the species or subspecies rank of a taxon we applied the species rank. Most regional flora descriptions in neighbouring countries adopt a similar line (e.g. ROTHMALER 1994, DOSTÁL 1989 etc.), fairly often differing from the definitions in Flora Europaea (TUTIN & al. 1964–1994), where in many instances the subspecies rank was preferred. Subspecies, however, were differentiated in this work only when they represented distinct morphological types not deserving the rank of species because of the presence of many transitional forms, the lack of evident habitat differences and, most importantly, the lack of differences in distribution ranges.

The list ignores hybrids almost entirely, as they have been currently reported from Poland in only in a very few instances; in most cases the authors of flora descriptions simply copied lists of hybrids from the accounts for neighbouring countries. A few taxa of hybrid origin that occur independently of the parent species are the only exceptions.

LATIN NOMENCLATURE

An attempt was made to include only the names of taxa whose correctness is not in doubt in terms of the International Code of Botanical Nomenclature (GREUTER & al. 1988). The following two principles were applied to any doubtful cases:

a) the most established names and those most often used in the flora accounts of neighbouring countries were adopted;

b) traditional definitions were used whenever possible, not to introduce changes without sufficient rationale.

The basis for choice of nomenclature was Exkursionsflora (ROTHMALER 1994). To a lesser extent we used Flora Europaea (TUTIN & al. 1964–1994), a work of the British perspective where the definitions of particular species, their position, rank and nomenclature in many instances do not correspond to the current state of knowledge. In cases of so-called "critical" or other doubtful groups, the views adopted in the flora accounts of neighbouring countries were followed, and above all the opinions given in detailed taxonomic studies (see references and notes).

The checklist also includes synonyms. Basically these cover the same scope as the second edition of Rośliny polskie (SZAFER, KULCZYŃSKI & PAWŁOWSKI 1953) and the first and second editions of Flora Polski (1919–1986). If a name was changed related to the names used in these works, the latter will appear in the checklist as synonyms. For the sake of good order, the relatively numerous names, for which the spelling of the genus and species epithets were correct but the taxon author's name was incorrectly spelled, were also included as synonyms. Also included as synonyms were names with incomplete sets of authors, and also variant spellings that might raise doubts. Only variant spellings whose identity is not open to question (e.g. silvestris – sylvestris) were left out. Abbreviations of authors' names follow the suggestions of BRUMMITT & POWELL (1992). Thus we avoided looseness in applying them. All the abbreviations of authors' names are explained in the list of authors, where we provide the full surname, first name(s), birth date and (if applicable) death date. In a dozen or so cases we did not manage to identify authors of species with certainty. In these circumstances we provided the abbreviations as they stood in the source of synonym, and appropriate note.

POLISH NOMENCLATURE

As in the case of the Latin names, any changes not required for good order were avoided.

New names were introduced for all species reported for the first time for Polish flora, or for species known earlier but not yet given Polish names, except for ephemerophytes and "small" species of the genus Taraxacum.

Subspecies nomenclature is introduced broadly for the first time, particularly when the subspecies were earlier named as species with their own, separate names. In these cases, the subspecies epithets which modify the species name are linked to the earlier names, except for nominative (typical) subspecies. In the latter case the adjective "typowy" (="typical") was added, for example:

before:

Agropyron intermedium – Perz siny

Agropyron trichophorum – Perz szczeciniasty

now:

Agropyron intermedium – Perz siny

Agropyron intermedium subsp. intermedium – Perz siny typowy

Agropyron intermedium subsp. trichophorum – Perz siny szczeciniasty.

In formulating new Polish names for subspecies that had no such names before, translation of the species epithet was the general practice. Other solutions were applied when translation, polonization or transliteration (e.g. of a person's name) yielded a name identical or very similar to another already in use or, if the name sounded clumsy or misleading.

New Polish names have also been consistently introduced when dividing a broadly defined genus. In such cases the Polish generic name was only retained for one species, namely the one that retained the earlier Latin generic name. For example:

before:

Polygonum [s. l.]– Rdest

now:

Polygonum – Rdest

Fallopia – Rdestówka

Reynoutria – Rdestowiec

When only the Latin generic name changed but the genus itself was not divided, the Polish name was retained, e. g.:

before:

Elisma natans – Elisma wodna

now:

Luronium natans – Elisma wodna.

In formulating Polish generic names, existing but out-of-use names have been applied whenever possible. Thus, for the genus Oreopteris (a part of the former genus Dryopteris) the name of zaproć was used; it was once used for the genus Limbosperma, in which Oreopteris limbosperma (once Dryopteris oreopteris) has sometimes been included.

Changes in Polish generic names usually did not involve any change in the species epithet except for the gender suffix, as well as for some particular cases, when, for example, the species epithet used so far has now been used to formulate the generic name, for instance:

before:

Lycopodium selago – Widłak wroniec

now:

Huperzia selago – Wroniec widlasty.

The most difficult problems appeared when establishing Polish names of ornamental plants. The flood of information about many new species and varieties imported to Poland in recent years, numerous translations of literature concerning them, and also the emergence of many popular magazines in this field have brought disorder to the process of formulating new plant names. That is why this group is rich in synonyms and homonyms which needed to be put in order. In selecting standard names in this group of plants, apart from the principles presented above, the usage frequency of a given name was used as a criterion.

CRITICAL REMARKS

The work as this cannot be (and presumably is not) free of certain errors, nor, inevitably, free of arbitrary solutions. We have striven, however, to reduce these imperfections to the minimum, by either leaving the difficult questions of nomenclature and taxonomy in the hands of the specialists, or consulting various questions with a wider group of a dozen or so colleagues from many Polish research centres, and also by referring to the latest works published abroad.

Undoubtedly the least completely solved is the Latin nomenclature of cultivated plants. Taxonomic complications associated with the occurrence of various cultivars, most often of hybrid origin, and the enormous confusion of nomenclature in this group did not permit clear-cut solutions in many cases.

DISTINGUISHING TYPEFACES AND SYMBOLS USED IN THE TEXT

Boldface, upright – correct generic name and species epithet, e.g.:

Bellis perennis L.

Boldface italics – synonyms. The correct name, given in the second position, is separated from it by an "=" sign, e.g.:

Myosotis hispida SCHLTDL. = Myosotis ramosissima ROCHEL

No boldface, upright – species that are ephemerophytes, and the taxa cultivated most frequently, e.g.:

Barbarea verna (SM.) R. BR.

No boldface italics – synonyms of ephemerophytes and the species cultivated more often; in the second position, after an "=" sign, the correct name in the corresponding font is given, e.g.:

Andropogon halepensis (L.) BROT. = Sorghum halepense (L.) PERS.

Special marks (before the taxon name):

* – anthropophyte established in Polish flora

[*] – species of uncertain status in Polish flora; opinions exist that it might be an anthropophyte

** – ephemerophyte

# – cultivated plant

? – doubts exist whether the taxon belongs to the Polish flora

+ – extinct in Poland

[+] – probably extinct in Poland.

In square brackets - [ ] - are included taxa erroneously reported for the flora of Poland or for other reasons (mentioned in "Notes") excluded from the Polish flora as separate species (subspecies).

•

REMARK. If a subspecies has no status indicated, then it has the same status as the species to which it belongs.

In the case of species listed in flora descriptions as ephemerophytes and also cultivated quite often, the name is only preceded by #, assuming that all the plants cultivated outdoors do transitionally revert to the wild state (ergasioephemerophytes).

When some subspecies of the one species differ in status, the higher of them is indicated next to the species' name.

All additional explanations are provided in hyperlinked notes.