Pollenatlas

species: Abies alba (European Silver-fir, White Silver-fir)
plant family: Pinaceae
at aerobiological analyses usually achieved determination level: Abies, Pinaceae 

photos: Landesagentur für Umwelt, Bozen (Italy) 

description:
outline: elliptical central body, with two lateral air sacs. The air bladders (sacchi) are clearly protruding from the body, forming half- to three quarters of a globe each. Largest of the sacchate pollen grains.
size: 124.8 (106.9-139.3) µm (longest diameter, measured with air bladders).
apertures: inaperturate (sulcate ?) 
pollen wall: central body: thick, rugulate exine; characteristic very long, thick columellae at the proximal pole; thick intine. Air bladders: pollen wall with large, irregular reticulate structure, often hardly visible due to air inside the sacchi (appearing black).
additional attribute: granular plasma.
note: similar pollen: Picea, Pinus, Cedrus

remarks to the plant:
Silver fir is a typical evergreen conifer of the (central) European montane stage. It prefers deep soils and shady stands with high air humidity. Solitary trees start to produce flowers with an age of about 30 years, but fertile plants in clusters must be aged 60-70 years for maturation. Mast years are usually every 5-8 years, sometimes we see half-mast years more frequent. The tree is monoecial, but single branches carry either female or male inflorescences, appearing in May on the uppermost branches. Male inflorescenes are yellow penduling cylindrical cones, female cones stand upright and have a reddish colour when young.

species: Acacia sp.
plant family: Mimosaceae
at aerobiological analyses usually achieved determination level: Mimosaceae 

photos: Landesagentur für Umwelt, Bozen (Italy)

description:
outline: bilateral pollen cluster, in polar view circular to elliptical; elongated elliptical in equatorial view (extremely seldom seen from this edge). The polyad consists of 16 almost cubed monads. 
size: polar axis: 44.9 (42.5-47.5) µm x 48.8 (45.5-52.4) µm (in polar view), single monads sized 13.5 (11.9-14.8) µm.
apertures: colporate (?) monads, apertures hardly visible by way of light microscopy. The exine shows a more or less quadrangular laesio on the distal pole of each monad. 
pollen wall: very thin, psilate exine, thin intine, pollen wall thickened to about 1-2 µm at the distal edges and the outer vertices (apertures ?).
note: similar pollen: Albizia

remarks to the plant:
The genus Acacia comprises numerous species of predominantly evergreen trees and shrubs. They are common in tropical and mild – temperate regions of Central- and South America, Polynesia, Australia, and Africa. Acacia dealbata (Silver Wattle, Mimosa) is one of the most frequently cultivated ornamental species. It is very popular because of the yellow – golden flowers.
Small globular to cylindrical flower aggregates appear during late winter and spring. Often they emit an intensive delicate scent, they produce big amounts of pollen, attracting honey bees.

species: Acer campestre (Field Maple)
plant family: Aceraceae
at aerobiological analyses usually achieved determination level: (Acer campestre), Acer

photos: Landesagentur für Umwelt, Bozen (Italy)

description:
outline: rounded triangular in polar view, in equatorial view circular to oval, slightly oblate
size: polar axis: 28.8 (26.0-30.0) µm, equatorial axis: 35.9 (34.0-39.0) µm
apertures: tricolpate pollen grain with long, broad colpi.
pollen wall: thin, striate exine, intine thickened and slightly protruding in the colpus area

remarks to the plant:
Hedge Maple (Field Maple) grows spontaneous in sunny deciduous forests, woodsides, groves and shrubbery, it is also planted as ornamental and hedges. The nicely grained wood of this European-West-Asian, summergreen species was formerly in style for woodturnings. Its yellow-green upright flowers are arranged in umbels or panicles with only few flowers each. They open in April/May short after budbreak. Leaves are deeply lobed (3-5 blunty lobes). Fruits are characterized by horizontally sticking out wings

species: Acer negundo (Box-elder, Ash-leaf Maple)
plant family: Aceraceae
at aerobiological analyses usually achieved determination level: Acer negundo, Acer

photos: Landesagentur für Umwelt, Bozen (Italy)

description:
outline: rounded triangular in polar view, elliptical in equatorial view
size: polar axis: 24.1 (21.8-26.7) µm, equatorial axis: 29.7 (27.7-31.6) µm
apertures: tricolpate pollen grain with long, acute colpi, seldom rounded at their tops. Colpi clearly circumscribed.
pollen wall: thin, rugulate exine, intine 1-2 µm, thickened and protruding in the colpus area

remarks to the plant:
Native from North America, the summergreen tree with unpaired pinnate leaves is frequently planted in parks and gardens, and may grow also spontaneous here and there. Growth and leaves are variable, many varieties, e.g. with variegate or aberrant foliage are cultivated by gardeners. Box elder is dioecic, the unisexual flowers without corolla appear short before budbreak in March or April. Female inflorescences are long, pendulate, paucifloral clusters; males are posted on long filaments, forming multifloral clusters.

species: Acer pseudoplatanus (Sycamore)
plant family: Aceraceae
at aerobiological analyses usually achieved determination level: Acer

photos: Landesagentur für Umwelt, Bozen (Italy)

description:
outline: rounded triangular in polar view, circular to elliptical in equatorial view
size: polar axis: 33.1 (31.0-35.0) µm, equatorial axis: 38.8 (37.0-41.0) µm
apertures: tricolpate pollen grain with long, wide colpi
pollen wall: thin, striate exine, intine 1-2 µm, thickened and somewhat protruding in the colpus area

remarks to the plant:
Sycamore Maple is a portly tree with deciduous foliage. Thanks to the lovely autumnal tints of its mostly five-lobed leaves, it is frequently used for roadside walks and parks. Spontaneous it grows in mixed forests in the mountains it climbs together with conifers up to timber line. Flowers are rich of nectar, unspectacular yellowish-green. They appear contemporaneously with the leaves in April/May, arranged in long, pendulous, multifloral panicles. Male stamens protrude from long filaments. Fruit wings are at acute or obtuse angle.

species: Acer saccharinum
plant family: Aceraceae
at aerobiological analyses usually achieved determination level: Acer saccharinum, Acer

photos: Landesagentur für Umwelt, Bozen (Italy)

description:
outline: rounded triangular in polar view, in equatorial view circular to oval, slightly oblate
size: polar axis: 30.8 (28.7-32.6) µm, equatorial axis: 32.5 (30.7-34.6) µm
apertures: tricolpate pollen grain with very long, broad colpi.
pollen wall: thin, regulate exine, intine approx. 1-2 µm, slightly thickened in the colpus area
note: the extremely fine structure of the exine becomes seldom visible below 1000x magnification under light microscope.

remarks to the plant:
Silver maple is originating from North American riverside forests and is planted for a long time in European parks. Simple leaf with 5 deeply cut lobes. Growing fast, the trees develop in short time to respectable height. The bright green leaves turn yellow orange to brownish red in autumn. Greenish or reddish unisexual flowers appear in clusters with end of February/March – long time before bud break.

species: Achillea millefolium (Yarrow)
plant family: Asteraceae
at aerobiological analyses usually achieved determination level: Asteraceae A-shape, Asteraceae

photos: Landesagentur für Umwelt, Bozen (Italy)

description:
outline: rounded triangular in polar view, circular to elliptical in equatorial view
size: polar axis: 30.2 (27-33) µm, equatorial axis: 25.9 (24-27) µm
apertures: tricolporate
pollen wall: very thick echinate exine, tectate (with columellae) with short, acute spines. Thin intine protuberantly underneath the pori.
note: similar pollen in various genera of the Asteraceae family (e.g. Leucanthemum, Matricaria, Anthemis …)

Pollen of Achillea stands representative for the Asteraceae A-form (=Achillea-form). It represents the medium-sized (20-30 µm) Asteracea pollen. Due to the tectate, spinate exine, it appears as if bearing three crows in optical polar view section.

remarks to the plant:
The group of yarrows is dispersed all over the Northern hemisphere. There are several sub-species, hardly to distinguish from each other, partly also forming hybrids. It is common in some types of meadows and pastures of valleys up to Alpine levels. It is little pretentious, and colonises even rocky areas, farmland and waysides. The plant is perennial and has aromatic, two-or threefold pinnate leaves. Numerous white or pink flower heads are arranged to an umbel-like panicle at the top of a stalk. Flowering time is July to September.

species: Aesculus hippocastanum (Horse-chestnut)
plant family: Hippocastanaceae
at aerobiological analyses usually achieved determination level: Aesculus, (Hippocastanaceae)

photos: Landesagentur für Umwelt, Bozen (Italy)

description:
outline: circular in polar view (rarely seen), elliptical in equatorial view (prolate)
size: polar axis: 25.4 (25-26) µm, equatorial axis 21 (20-22) µm.
apertures: tricolpate pollen with long, clearly defined apertures. The membrane of the apertures is covered with conspicuous spines, up to 1 µm long, these exine rests are clearly visible as granules in top view.
pollen wall: very thin, psilate exine, intine thickened underneath the apertures, protruding at the pori

remarks to the plant:
Horse chestnut was introduced to Europe in the XVIth century from Southeast Europe (Balkans) – Western Asia. The tree is mainly grown for ornamental purposes, in gardens and in parks, and forms fine avenues, which in the spring, when the trees are in full bloom, present a beautiful sight. On the branches, just beneath the sticky buds, there is a horseshoe-like mark, from which the tree gets its name. Because of this association with horses, conkers used to be ground up and fed to horses as a remedy for breathing difficulties. The lobed leaves are well known to everybody. Flowers appear in May in upright cones.

species: Ailanthus altissima (Tree of Heaven)
plant family: Simaroubaceae
at aerobiological analyses usually achieved determination level: (Ailanthus altissima), Ailanthus

photos: Landesagentur für Umwelt, Bozen (Italy)

description:
outline: somehow hexagonal in polar view, elliptical in equatorial view
size: polar axis: 25 (24-26) µm, equatorial axis 27.7 (27-29) µm.
apertures: tricolpate pollen with long, narrow colpi.
pollen wall: reticulate exine, lumina open and elongated towards the colpus, so that the reticulum walls appear like striae. Thin exine, thickened underneath the apertures.

remarks to the plant:
Originating from China, Tree of Heaven is often planted and grows also spontaneous in Europe. It grows predominantly on stony grounds in temperate or warm climates and is widely common in unattended urban areas. Thanks to its resistance against pollution, it is well qualified for use at frequented roads. The deciduous tree grows to a height of about 25 m with blunt, clumsy branches, which give to it an odd appearance after the leaves have fallen. The leaves are odd-pinnate, each consisting of from 10 to 20 pairs of leaflets and a terminal one. The leaflets are about 2 inches long, ovate, smooth, acute, and have a few blunt, glandular teeth at the base (hence, the specific name, glandulosa). The flowers are small, green, and collected in large terminal panicles. They are polygamous, or generally dioecious, flowering in June and July. They produce much nectar, attracting insects (mostly Diptera). Pollen production is high, therefore some partition becomes even airborne.

species: Albizia julibrissin (Silktree, Mimosa)
plant family: Mimosaceae
at aerobiological analyses usually achieved determination level: Mimosaceae

photos: Landesagentur für Umwelt, Bozen (Italy)

description:
outline: bilateral pollen association, rounded-elliptical in polar view (most frequent appearance), rarely seen in equatorial view where it appears as elliptical polyad, composed of 16 almost cubic monads
size: polyad: 87.7 (83-93) by 80.7 (75-88) µm (in polar view), monads 26.4 (25-28) µm
apertures: tetraporate monads, apertures almost invisible under light microscope inside the intact polyad
pollen wall: pollen wall about 2 µm thick. Exine psilate, intine thickend at the corners, forming onci.
note: Acacia has similar pollen

remarks to the plant:
We found a very neat description in the web: This fast-growing, deciduous tree has a low branching, open, spreading habit and delicate, lacy, almost fern-like foliage. Fragrant, silky, pink puffy pompom blooms, two inches in diameter, appear in abundance from late April to early July creating a spectacular sight. But the tree produces numerous seed pods and harbors insect (webworm) and disease (vascular wilt) problems. Although rather short-lived (10 to 20 years), Mimosa is popular for use as a terrace or patio tree for its light, dappled shade and tropical effect. Its deciduous nature allows the warming sun to penetrate during the winter. There are too many other high-quality trees in this cruel world to warrant planting this tree. (source: Edward F. Gilman and Dennis G. Watson, Fact Sheet ST 68, November 1993, US Forest Service)

species: Alnus glutinosa (Alder)
plant family: Betulaceae
at aerobiological analyses usually achieved determination level: Alnus

photos: Landesagentur für Umwelt, Bozen (Italy)

description:
outline: oblate, pentangonal or quadrangular in polar view, elliptical in equatorial view
size: polar axis: 22.1 (20-23) µm, equatorial axis 25.5 (24-26) µm
apertures: penta-(tetra)porate pollen with protruding, elliptical pori, seldom also hexaporate; vestibulate. Pori surrounded by annular thickenings.
pollen wall: thin scabrate exine with thickened bows from one porus to each other, both on the proximal and the distal hemisphere. A thin exine forms a flat vestibulum underneath the porus; small oncus.
additional attribute: finely granulate plasma

remarks to the plant:
A native tree of damp or wet ground, on waterlogged soil, often found beside rivers, ponds and canals or in wet woodland. Root nodules contain nitrogen fixing Actinomycetes, which help the plant to colonize poorly nutritious soils. Male flowers are produced in summer and open in early spring in long narrow catkins. The female flowers, produced at the same time, are borne in woody, rounded structures resembling tiny pine cones which persist on the tree for more than one season. Pollination and seed dispersal are by wind.

species: Ambrosia artemisiifolia
plant family: Asteraceae
at aerobiological analyses usually achieved determination level: Ambrosia, (Asteraceae)

photos: Landesagentur für Umwelt, Bozen (Italy)

description:
outline: circular in polar view, in equatorial view circular or a little elliptical
size: polar axis: 17.4 (16.8-17.8) µm, equatorial axis: 18.8 (17.8-19.8) µm
apertures: tricolpate pollen grain with very short, cuspidal colpi. It is often described in literature as tricolporate (with lolongate pori and short colpi). Pori are not detectable in light microscopy.
pollen wall: up to 2 µm thick, echinate exine, spines rather flat with broad root. Thin Intine, sometimes thickened underneath the apertures.
note: similar pollen grain: Xanthium.

remarks to the plant:
Short ragweed has been introduced to Europe from North America. It grows on waste land, acres, and along roadsides. Pollen of this annual, wind pollinated plant is abundant in the air from August to September. Each leaf is divided into narrow segments which are in turn irregularly lobed. Male flower spikes carry numerous naked flowers of greenish-yellowish colour which appear at top of the plant. Female flowers are placed singular below the male inflorescences in the branch axes.

species: Anemone nemorosa (Wood Anemone)
plant family: Ranunculaceae
at aerobiological analyses usually achieved determination level: Anemone, Ranunculaceae

photos: Landesagentur für Umwelt, Bozen (Italy)

description:
outline: in polar view rounded triangular or circular, elliptical in equatorial view
size: polar axis: 24.2 (23-26) µm, equatorial diameter 28.7 (26-30) µm
apertures: tricolpate pollen with rounded colpi, membrane covered with fine granules
pollen wall: thin, scabrate exine, intine as thick as the exine, thickens slightly in the zone around the colpi, sometimes protruding
note: similar pollen are seen at Pulsatilla (larger), and Clematis (smaller)

remarks to the plant:
Wood Anemone is a European species. It has a long, tough, creeping root-stock, running just below the surface; it is the quick growth of this root-stock that causes the plant to spread so rapidly, forming large colonies in the moist soil of wood and thicket. The deeply-cut leaves and star-like flowers rise directly from it on separate unbranched stems. Some distance below the flower are the three leaflets, often so deeply divided as to appear more than three in number and very similar to the true leaves. They wrap round and protect the flower-bud before it unfolds, but as it opens, its stalk lengthens and it is carried far above them. (Source: A Modern Herbal, Mrs. M . Grieve, Botanical.com)

species: Anthriscus sylvestris ( Cow Parsley)
plant family: Apiaceae
at aerobiological analyses usually achieved determination level: Apiaceae A-shape, Apiaceae

photos: Landesagentur für Umwelt, Bozen (Italy)

description:
outline: elongated elliptical, prolate in the prevailing equatorial view.
size: polar axis: 28.5 (28.0-30.0) µm, equatorial axis: 16.9 (16.0-18.0) µm
apertures: tricolporate pollen grain with long, narrow colpi and elliptical pori (longer axis in equatorial direction)
pollen wall: thin, scrabrate exine, thin intine, sometimes thickened underneath the porus area
note: many other plants of the Apiaceae (=Umbelliferae) family have similar pollen

Pollen of Anthriscus sylvestris is presented here representative for the Apiaceae A-form (=Anthriscus-form)

remarks to the plant:
Cow Parsley is found on meadows, in hedges and along waysides. In meadows with intensive fertilisation, it may become the dominant weed. The plant is perennial, herbaceous, has pinnate leaves and white flower umbels. Flowering time lasts from April to August, as the umbels develop one after the other. The small, tiny single flowers are visited by different insects, such as flies, beetles or bees.

species: Artemisia vulgaris (Mugwort)
plant family: Asteraceae
at aerobiological analyses usually achieved determination level: Artemisia

photos: Landesagentur für Umwelt, Bozen (Italy)

description:
outline: circular
size: polar axis: 20.5 (20-22) µm, equatorial axis: 22.5 (20-24) µm
apertures: tricolporate with long, acute colpi and round, distinctly circumscribed pori
pollen wall: echinate exine, tectate (with columellae) with very small rudimentary spines. In optical section, the exine appears sickle-shaped, showing nicely the columellae. It tapers of towards the colpi. The thick intine often protrudes through the pori.
additional attribute: granular plasma

remarks to the plant:
Mugwort is widespread nearly all over Eurasia. It is common along waysides, river banks, and on waste land, prefers disturbed soils and eutrophic stands. The plant grows perennial and carries pinnately-lobed leaves with deeply cut lobes, of green colour above and white-downy below. Numerous flower heads stand in dense branched panicle-like inflorescences. Flower heads oval, 2-3 mm in diameter, red-brown, inner tubular florets bisexual, outer ones female. A fully developed specimen may carry up to 500.000 flower heads! Flowering time is July to September.