Parrotia persica (DC.) C.A.Mey.

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Credits

Owen Johnson (2024)

Recommended citation
Johnson, O. (2024), 'Parrotia persica' from the website Trees and Shrubs Online (treesandshrubsonline.org/articles/parrotia/parrotia-persica/). Accessed 2024-06-19.

Common Names

  • Persian Ironwood
  • Irontree
  • Parrot Tree

Synonyms

  • Hamamelis persica DC.
  • Parrotia siderodendron C.A.Mey. ex Ledeb.

Glossary

dbh
Diameter (of trunk) at breast height. Breast height is defined as 4.5 feet (1.37 m) above the ground.
montane
Of mountains.

Credits

Owen Johnson (2024)

Recommended citation
Johnson, O. (2024), 'Parrotia persica' from the website Trees and Shrubs Online (treesandshrubsonline.org/articles/parrotia/parrotia-persica/). Accessed 2024-06-19.

A tree to 20(–25) m, sometimes a thicket-forming shrub; suckering and also naturally layering. Bark pale grey to rich brown, exfoliating in thin, smooth scales; new bark beige to orange. Shoots grey-brown, with stellate hairs at first; leaf-buds brownish, scurfy. Leaf ovate, oblong or obovate, 6–10(–14) × 4–8 cm, rounded to cuneate at the base (often assymetrically), bluntly acute at the tip; entire or with a few coarse, shallow, irregular teeth; rather glossy and almost glabrous above and with sparse stellate hairs beneath; 3-veined from the base and with about 5–7 further pairs of major side-veins; autumn colour yellow to purple; petiole short (2–6 mm), pubescent; leaf stipules large, broadly lanceolate, quickly shed. Flowers opening in late winter or early spring in sessile clusters c. 12 mm wide, with bright red stamens; sepals c. 5 mm long, lobed but not fused into a disk. Bracts brown and hairy outside, green inside, 6–10 mm long, ovate. Seeds to 9 mm long, bright brown, pointed at one end. (Bean 1976; Andrews 2008).

Distribution  Azerbaijan Near the Caspian Sea Iran In forests near the Caspian Sea

Habitat Mountain forests, to 1400 m asl; sometimes forming pure stands (Parrotietum).

USDA Hardiness Zone 5

RHS Hardiness Rating H6

Awards AGM

Conservation status Not evaluated (NE)

Like its Chinese counterpart Parrotia subaequalis, the Persian Ironwood is a relic tree, confined to a small area of montane forests. Unlike the Chinese plant, however, it remains abundant within these (less biodiverse) forests and can indeed be the dominant tree (Douglas & Sjöman 2021; Nicholson 1989), although forest clearance and increased grazing pressures now present a threat (Andrews 2008).

The species was named by the Russian botanist Carl Anton von Meyer in 1831, and was one of many plants found during the previous year’s expedition to Elburz Mountains led by General Georgi Arsenievich Emmanuel. Meyer named the genus after his friend and predecessor at the University of Dorpat (now Tartu University, Estonia), the German naturalist Georg Friedrich Parrot. Parrot was a suitably colourful character who had also explored the eastern Caucasus, climbing Mt Ararat in 1829 (Murray 2017) – although it is only in the English language that his name lends itself to assocation with garish tropical birds. The first botanist to introduce Parrotia to the west may have been Friedrich Fischer, the Director of the Imperial Garden at St Petersburg, who had collected in what is now Azerbaijan and who in 1846 sent two potted seedlings to the Royal Botanic Gardens, Kew (Andrews 2008). The next recorded introduction, also to Kew, was made by Surgeon-Major J.E.T. Aitchison with seed from Iran in 1885 (Bean 1976).

By this time, Parrotia persica was modestly established in English gardens. The old tree at the Cambridge University Botanic Garden seems to have been raised from seed sent from Kew in 1880 (Murray 2017). Queen Victoria’s specimen at Osborne House on the Isle of Wight was mature enough to flower in 1890; one planted after 1874 by Edward Pember at Vicar’s Hill in Hampshire first fruited in 1900, and one grown by Canon Henry Ellacombe at Bitton Old Vicarage in Gloucestershire flowered in 1904 (Andrews 2008). All of these places are much less rainy (and sometimes frostier in winter) than the montane temperate rainforests to which the species in confined in the wild, but the Persian Ironwood has proved itself remarkably tough and adaptable in cultivation: it will survive in all except the very coldest parts of Europe and also flourishes in lime-rich soils (Edwards & Marshall 2019); it is very drought-tolerant – something that makes it a species of particular interest for increasingly drought-prone microclimates in southern England and central Europe – but it can also cope with wet or compacted ground conditions. In Belgium multiple clones of Persian Ironwood from Iranian and Azerbaijani provenance have survived both the very cold winter of 2009–10 when temperatures dipped to –19°C, and the very hot summer of 2022 when 41°C was recorded in the shade (C. Crock pers. comm. 2024). In the UK and Ireland Persian Ironwood has traditionally found its limits in the cooler shorter summers of Scotland and Northern Ireland – the northernmost recorded on the Tree Register being a mature specimen only 4 m tall in the Cruickshank Botanic Garden in Aberdeen (Tree Register 2023) – but more recent introductions and horticultural selections, not to mention a changing climate, may see its useful range expanded into these areas before long. The tree is troubled by remarkably few pests and diseases, although Japanese Beetle in the south-eastern United States and Phytophthora ramorum in Atlantic areas of northern Europe may cause some damage (Dirr 2009). Among trees of modest stature it also seems long-lived; Canon Ellacombe’s tree at Bitton was still thriving, with a short bole 66 cm thick, in 2014 (Tree Register 2023). The tendency of its tangled lower branches to inosculate and to layer creates a robust and storm-proof structure, and the heavy iron-hard timber is very durable.

Another fine specimen in the garden of Normanville on the Channel Island of Guernsey was once the Caledonia Nursery’s stock plant, and by 1903 was being propagated here by layering (R. Waterman pers. comm.). For a long time, layering remained the main method of propagating this attractive garden tree, but detaching suckers, which are occasionally produced some distance from the stem, especially when the tree is grown in a meadow (C. Crock pers. comm. 2024) is another option. Where several clones are grown together (and where summers are sufficiently warm) cultivated plants will often produce seed in quantity (C. Crock pers. comm. 2024). W.J. Bean (1976) also mentions grafting onto Hamamelis virginiana, but the resultant product may have been less long-lived and no such grafts seem to survive. Vegetative reproduction inevitably results in an impoverished gene-pool and nearly all the mature Parrotia persica in Britain and Ireland today seem to exhibit a curious growth shape: above a very short bole, branches arch widely and terminate in long, wandering and almost level shoots clad in very sparse foliage – a feature perhaps inherited from one of Fischer’s two original pot-plants. (These wandering shoots are also characteristic of a shade-tolerant understory species seeking gaps in the canopy, and may partly be a response to the UK and Ireland’s generally low light-levels.) Attractively distinct though it is, this habit has probably told against the Persian Ironwood as a garden feature – an unusually large garden certainly being indicated. Many students of Britain’s trees will have assumed that this is simply the species’ natural way of growth, but plants in the native forests are highly variable, some forming symmetrical spire-like crowns and others growing long boles which are straight enough to be used for telegraph poles (Douglas & Sjöman 2021; Andrews 2008). Two Parrotia at Whitfield, Herefordshire, are supposed to have been brought back by a former owner, Meysey Clive, from his travels in Iran in 1934 (E. Clive pers. comm.), but their very ‘normal’ sprawling habit may imply otherwise. One exhilaratingly different-looking Parrotia, meanwhile, was recorded for the first time in 2023 in a long-overgrown private garden on the Isle of Wight; it has a richer brown bark than the older UK specimens and a strong, rather symmetrical and upright habit, and is the UK champion at 18.4 m × 69 cm dbh (Tree Register 2023; T. Christian pers. obs.).

Parrotia persica was introduced to the Harvard Botanic Garden in Massachussetts, USA, as a seedling of unrecorded origin in 1880 (but most probably from Kew); one cutting struck from this the following year still survives at the nearby Arnold Arboretum, where its spread has exceeded 23 m (Andrews 2008; Jacobson 1996). Another much-admired early planting is at Biltmore Gardens in North Carolina, whilst Lawrence Hatch champions the more showily flaking patchwork bark of a third and multistemmed plant of this vintage at the Maymont Foundation Garden in Virginia (Hatch 2021–2022). These older American specimens, while still spreading, tend to grow more symmetrically and densely than their English cousins (q.v. the gallery of images in Stewart 2010). They are hardy at least as far north as Lisle, Illinois (North American Hardiness Zone 5b) where young plants at the Morton Arboretum can suffer minor dieback in hard winters (Dirr 2009). The flowers with their crimson stamens can be quietly attractive at the end of a mild winter in north-west Europe but tend to be carried more patchily in the eastern United States (Dirr 2009), but autumn colours ars typically brighter in a continental climate; these can show a gamut from lemon yellow to crimson and even plum purple, according to the individual plant. (Orange predominates in the older English stock.) Although this is naturally an understory tree tolerant of dense shade, an open sunny situation is recommended even in America for the best fall show (Dirr 2009), and the same would appear to be true at Arboretum Wespelaar in Belgium (T. Christian pers. obs.).

The species’ general toughness and adaptability, combined in particular with its striking bark and restrained seed production, would seem to recommend the Persian Ironwood as a street tree, but its use in confined spaces has had to wait until less spreading phenotypes became available. Two new introductions from the Elburz Mountains in Iran reached Kew in the 1970s: FLSX 344 in 1977 followed by Cobham 11 a year later (Andrews 2008). The seedling plants from FLSX 344 tend to be slightly more erect than the older cultivated specimens, often growing numerous near-vertical stems from an untidily tangled base; 1977–6798*1 in the shelter of the Bluebell Wood at Kew was already 16.7 m high in 2022 (Tree Register 2023) and looked as if it was going to grow much taller. Several trees in the City of Westminster Cemetery at Hanwell a few kilometres distant, which was being developed as an urban arboretum around this time, are remarkably similar in form, although not recorded as deriving from FLSX 344. The tangled growth-form exhibited by so many diverse Parrotia persica can largely be sorted out by formative pruning, something which makes the mature bark easier to appreciate; the suckering tendency is a demerit for low-maintenance woodland gardens but ceases to be a problem in a lawn or pavement – or within grazed parkland, as is the case for one fine specimen at Stanage in the Welsh Marches.

Today, the species is available in the west in considerable genetic diversity. A collection made in Azerbaijan by the Belgian nurseryman Dominique Duhaut has produced two clones with red autumn colour, ‘Felicie’ and ‘Red October’ (Andrews 2008; Arboretum Wespelaar 2023), while Pan-Global Plants in the UK offers seedlings from NJM 13.005, also collected in Azerbaijan (Pan-Global Plants 2023). Selections such as ‘Jennifer Teates’, PERSIAN SPIRE® and ‘Vanessa’ form narrower and neater crowns (albeit with varying degrees of reliability – see cultivar accounts below). Parrotia persica is also now sold in Australia (e.g. Fleming’s Nursery 2023) and New Zealand (e.g. Leafland Wholesale Tree Nursery 2023), and should luxuriate in a range of antipodean microclimates, although it is interesting to note that in New Zealand the autumn colour is almost exclusively yellow (P. Cooke pers. comm. to T. Christian, 2023) which suggests a highly restricted gene pool here.

Parrotia persica has crossed with a very different but closely related tree, the evergreen Chinese shrub or small tree Sycopsis sinensis, to produce the horticultural curiosity × Sycoparrotia semidecidua. Hybrids between Parrotia and the evergreen east Asian genus Distylium have also been reported from Spain and from the south-eastern United States (F. Garin and Z. Hill pers. comms.)


'Alata'

An ironwood originally obtained from Marco Sartori in Italy by Abraham Rammeloo and introduced to the UK by Chris Lane. The name is derived from the Italian word for ‘winged’, in reference to the ‘wavy horizontal outer branches which look like wings’ (C. Lane pers. comm. 2023) (but also being a Latin word with the same meaning may render it illegitimate as a cultivar name). An example planted at the Sir Harold Hillier Gardens, UK, in 2011 (Royal Botanic Garden Edinburgh 2023) shows good autumn colour.


'Bella'

Synonyms / alternative names
Parrotia persica 'Belle'

A vigorous, rather upright clone with slightly twisted leaves which flush reddish-purple and turn deep crimson in autumn; selected from wild seed by Chris van der Wurff in the Netherlands (Andrews 2008; Edwards & Marshall 2019).


'Biltmore'

The tree at Biltmore Gardens, North Carolina, which is one of the oldest in the United States, was vegetatively propagated in the mid 1990s by Earth Shade Nursery (Jacobson 1996). Its leaves flush reddish-purple and its autumn colour varies from yellow to purple (Hatch 2021–2022). It was introduced to the UK by Chris Lane in the late 1990s (C. Lane pers. comm. 2024) and is represented at the Sir Harold Hillier Gardens, UK (Royal Botanic Garden Edinburgh 2023).


'Burgundy'

A seedlling selected at Junker’s Nursery, Somerset, UK, in the mid 1990s for its purple spring flush and burgundy autumn colour (Andrews 2008; Edwards & Marshall 2019).


'Cherry Tip'

A form with reddish purple margins to the young leaves, a feature of many seedlings such as ‘Purple Halo’, ‘Purple Moon’ and ‘Purple Rim’ which are all very similar, approaching indistinguishable, except for unique origins, and not really worthy of cultivar staus. This clone was obtained by Chris Lane from Arboretum Kalmthout, which in turn obtained their plant from Esveld in Boskoop, The
Netherlands (C. Lane & A. Rammeloo, pers. comm. 2024).


'Chrishaven1'

Synonyms / alternative names
Parrotia persica GOLDEN BELLTOWER™
Parrotia persica 'PP 28584'
Parrotia persica BELLTOWER
Parrotia persica GOLDEN BELL TOWER

A seedling selected in the late 1990s by Ken Christianson of Chrishaven Trees, Washington State, USA, for its neat, columnar habit and yellow autumn colour (Plants Nouveau 2023). Chris Lane introduced it to the UK in 2019 (C. Lane pers. comm. 2024).


'Cobhay Upright'

Synonyms / alternative names
Parrotia persica 'Fastigiate'

A narrow, upright selection from Junker’s Nursery, Somerset, UK (Junker’s Nursery 2023).


'Compacta'

Described as a compact and upright selection reaching eight metres in height and four in spread (Bihaki 2019). The latinate name would only be legitimate if ths is an old clone, named before 1959.


'Diane'

Named by Chris Lane in 2016 and raised from seed of Parrotia persica ‘Pendula’, this clone has a fairly upright habit with weeping tips to the branches, foliage similar to ‘Pendula’ in shape, with a heavy suffusion of reddish purple on young foliage, later turning green. Autumn colour is yellow, a most distinct cultivar. (C. Lane & A. Rammeloo pers. comm. 2024).


'Felicie'

Selected for its rich autumn colour by Rein Bulk who spotted it in a row of seedlings of Azerbaijani provenance in Dominique Duhaut’s nursery. Duhaut later named it for his daughter and it was distributed by Mark Bulk in the Netherlands from around 2000 (Andrews 2008; C. Lane pers. comm. 2024). A sister-seedling to ‘Red October’, both cultivars can begin to colour after the first strong heat of summer, sometimes as early as July (C. Crock pers. comm. 2024). The plant has a wide-spreading habit.


'Globosa'

A compact selection (Dirr 2021). The latinate name is considered valid by the Royal Horticultural Society (Royal Horticultural Society 2023), implying that this is an old clone already in commerce by 1959.


'Henny's Dwarf'

Sold as a dwarf selection, but growing quite rapidly to 4.5 m tall by 2021 in Michael Dirr’s garden in Georgia, USA (Dirr 2021), an experience shared by Chris Lane in the UK (C. Lane pers. comm. 2024).


'Het Plantsoen'

Scions of a hundred-year-old tree in Het Plantsoen park in Leiden, the Netherlands, which spreads widely but is only about two metres tall; sold by Esveld nurseries from 1992 (Andrews 2008).


'Horizontalis'

An old, wide-spreading, semi-weeping selection, perhaps originating from cuttings from side-branches (Royal Horticultural Society 2023; Wikipedia 2023). Chris Lane has observed a propensity of plants in wetter parts of the UK, especially Cornwall and Devon, and wonders whether it might be climate related (C. Lane pers. comm. 2024).


'Inge'

Synonyms / alternative names
Parrotia persica RUBY VASE®

A 2001 selection from J. Frank Schmidt, Oregon, USA with ruby-red young leaves (Dirr 2009; Hatch 2021–2022), paler than in most similar cultivars (C. Lane pers. comm. 2024). By 2021 RUBY VASE® was probably the most popular Parrotia persica clone in the United States (Dirr 2021).


'Jennifer Teates'

Scions of a tree in Alex Niemiera and Jennifer Teates’ garden in Blacksburg, Virginia, USA, which when 6 m tall retained a neatly upright habit, superior to that of ‘Vanessa’ (Dirr 2011).


'JL Columnar'

Synonyms / alternative names
Parrotia persica PERSIAN SPIRE™
Parrotia persica 'Jlpn01'

A selection made by John Lewis in Oregon, USA, with a compact and upright habit, and narrow, densely held leaves which flush purplish and retain a purple margin through summer before turning red to yellow in autumn (Edwards & Marshall 2019; City of Seattle 2023).


'Jodrell Bank'

Scions of a slender, rather bushy tree in the Lovell Quinta Arboretum at Jodrell Bank, Cheshire, UK, with good but not reliable autumn colour (Edwards & Marshall 2019).


'Keith Silver'

Named by Lawrence Hatch from a tree at the Charles R. Keith Arboretum in North Carolina, USA, remarkable for its upright habit and in particular for its silver-and-grey bark which lacks the species’ usual amber and brown tints (and thus more closely resembles the bark of old Parrotia subaequalis in China). It may not yet have been commercially propagated (Hatch 2021–2022).


'Kew Weeping'

Common Names
Weeping Ironwood

Synonyms / alternative names
Parrotia persica 'Kew's Weeping'
Parrotia persica 'Pendula'

Charles Coates, Propagator-Foreman at the Royal Botanic Gardens, Kew, selected this clone from a batch of seedlings in 1934: it is a remarkable sport, forming a low mound of strongly weeping shoots and branches. The original tree still grows near King William’s Temple at Kew, while the younger tree near the Cedar Vista was donated in 1975 by Hilliers Nursery, who had recently propagated the clone (Andrews 2008). Charles Erskine named the clone ‘Pendula’ in 1989, but Latin cultivar names published after 1959 are not permitted under the rules of nomenclature for cultivated plants, and Chris Lane recommends adopting the alternative ‘Kew Weeping’ which is extensively used in North America for the same material, where it was intorduced via the Arnold Arboretum in 1966 (Jacobson 1996; C. Lane pers. comm. 2024).

Chris Lane obtained propagation material from Kew in early 1998; his Witch Hazel Nursery has been responsible for ensuring this very attractive cultivar has become more widely distributed in recent years, while a group of pendulous plants in Volcji Potok Arboretum in Slovenia, planted by Joze Strager in the mid 1960’s, are probably ultimately traceable to Kew via Lombart’s Nursery in Zundert, The Netherlands, and Sir Harold Hillier (C. Lane & A. Rammeloo pers. comm. 2024).


'Lamplighter'

Synonyms / alternative names
Parrotia persica 'Variegata'

Perhaps the showiest of the few variegated clones of Parrotia persica, ‘Lamplighter’ was selected by the late Stephen Taffler and propagated by Junker’s Nursery in Somerset, UK. Its leaves have a broad but irregular creamy margin (which can turn pink in colder weather). Like many variegated trees it is prone to revert and will scorch in bright sun (Dirr 2009). It has also been distributed under the name ‘Variegata’, but this latinate form is not valid.


'Persian Carpet'

A selection with amber and orange autumn colour named by Chris Lane from a very low, spreading example in the Valley Gardens, Windsor Great Park, UK (C. Lane pers. comm. 2024). However, a 2015 accession at the Royal Botanic Gardens, Kew, was 3 m tall by 2022 (Tree Register 2023).


'Persian Lace'

A sport with a broken variegation of white and grey-green across the leaf (Dirr 2012; Esveld nursery 2023). This may be the same clone as ‘Persian Rose’, described by Lawrence Hatch (only) as a plant selected in 1999 at Rippingdale Nursery (a name which may also be misprinted; Hatch 2021–2022).


'PPCM2'

Synonyms / alternative names
Parrotia persica CONTEMPLATION®

Scions of a tree at the Morris Arboretum, Pennsylvania, USA, which retains a neat, upright habit. Its dark green leaves turn a kaleidoscope of colours in autumn (Dirr 2021).


'PPS551'

Synonyms / alternative names
Parrotia persica STREETWISE®

An upright selection from the United States, suitable for street planting (Dirr 2021).


'Purple Halo'

Selected by the late Peter Chappell at Spinners Nursery, Hampshire, UK; the leaves flush purplish and retain a purple margin (Dirr 2009).


'Purple Moon'

Another selection from Peter Chappell at Spinners Nursery, UK, which is described as retaining purple leaves. However, the colour fades through summer (Dirr 2021).


'Purple Rim'

One of several selections with a purplish flush, the colour lasting around the leaf margin (Dirr 2021).


'Red October'

Synonyms / alternative names
Parrotia persica 'Red Bull'

Parrotia persica ‘Red October’ was selected at Arboretum Wespelaar in Belgium by Philippe de Spoelberch from plants of Azerbaijani provenance that had been obtained from nurseryman Dominque Duhaut. The seed had originally been obtained from a Russian merchant. The clone was named ‘Red October’ by Canadian nurseryman Paul Reimer. Its autumn colour reliably passes from orange-gold to a rich wine-red, lasting until the first heavy frosts of December. Several sister seedlings grow in a meadow at Wespelaar and exhibit yellow autumn colour, but none have been named (C. Crock pers. comm. 2024). The original seedling has grown into a remarkably low and spreading plant, only 3.5 m tall after twenty years but twice as wide; it could be pruned to a narrower shape (Arboretum Wespelaar 2023).


'Summer Bronze'

A seedling selected by Kevin Hughes (then of Spinners Nursery, Hampshire, UK) with a bronze-coloured flush; in commerce by 2008 (Royal Horticultural Society 2008). The colour lasts through summer in new leaves on the outer crown (Edwards & Marshall 2019).


'Tortworth Court'

Named by Chris Lane from a plant in the Tortworth Hotel Grounds (Bristol, UK) with a fairly upright habit and matt green leaves which turn yellow in autumn (C. Lane pers. comm. 2024).


'Tűzmadár'

A Hungarian selection with intense red autumn colour (Moga nurseries 2023). The name celebrates another colourful bird and means ‘kingfisher’ in Hungarian.


'Vanessa'

Synonyms / alternative names
Parrotia persica 'Select'

Awards
AGM

A seedling selected by Alphons van der Bom in the Netherlands in 1975 for its upright habit and orange to purple autumn colour, and named in 1983 after the genus of brightly colour butterflies (Andrews 2008). Some of its leaves retain reddish margins through summer. By 2023 ‘Vanessa’ had become the default Parrotia in the UK for planting in confined spaces, but like many selections it broadens and grows less tidy with age; a 1998 accession at the Savill Garden, Windsor, was 11.5 m tall by 2021 and had matured into a rather untidy bush (Tree Register 2023).

According to Susyn Andrews, the same clone is sold in the United States as ‘Select’, being first offered by Buchholz and Buchholz in Oregon in 1993–4 (Andrews 2008; Jacobson 1996). However, more than one clone may be involved since ‘Select’ in America is said to show yellows rather than the mix of darker autumn colours seen in Europe (Dirr 2021), but it is worth noting that yellow is the predominant autumn colour in all parrotias in New Zealand, so other factors may be involved.


'Viktor'

‘Viktor’ originated from a graft of a branch bearing very dark coloured foliage, from a plant in Dominique Duhaut’s nursery; it was later named for Dominique’s son. According to some sources, the parent plant was a second generation seedling from the batch of plants that first gave rise to ‘Felicie’ and ‘Red October’ (q.v.), although Chris Lane suggests it was seed of Iranian provenance collected by Duhaut himself (C. Lane & A. Rammeloo pers. comm. 2024). ‘Viktor’ bears remarkably deep autumn colour but the display comes later than in those cultivars (C. Crock pers. comm. 2024). The same batch of seedlings that gave rise to ‘Viktor’ contain other, as-yet unnamed clones that show remarkable variation in leaf size and shape, and overall habit; some are likely to be named in the future (C. Lane & A. Rammeloo pers. comm. 2024).