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Oaks on Postage Stamps
The late Stelian Radu, one of the early members of the IOS, wrote an article in International Oaks No. 3 (1993) about postage stamps that featured oaks: "The Oaks in Philately." It was based on his own collection, which focused on stamps related to trees and forests, and it included some illustrations in black and white. I thought it might be interesting to update the article to include other stamps with oaks, using the research capabilities that the internet now offers, and to illustrate them with color reproductions. The project became a bit of a rabbit hole, as it turns out that in addition to the stamps that Stelian had not included, a large number of countries have issued oak-related stamps since he wrote the article. It might be easier to list the countries that haven't done so! You can see the result of the research below.
I found over 100 (see Update below) stamps that prominently featured an oak tree, oak leaves, or acorns. As might be expected, Quercus robur is by far the most philatelic oak, chosen by many European countries. But there are some interesting rarities: kudos to Costa Rica for putting the rare Q. brenesii on a stamp; a few countries have highlighted their endemic species, or at least species that would be endemic or nearly so before they were synonymized; Germany issued two poignant post-war stamps in which oaks eloquently symbolize the hope of new beginnings; an oak cultivar has made it on to a stamp (issued by Belgium, of course); and surely the prize for rarity goes to Abkhasia, who put two oak fossils on their stamps. Interesting to note that countries in oak diversity hot spots like Mexico, China, and South East Asia are surprisingly absent.
If you know of any that I have missed, click here to let me know, or if you are an IOS member you can log in and post a comment below.
Update (April 2024)
In January 2024 a friend who had read this blog presented me with a stamp album containing a large number of stamps featuring oaks. It was a beautiful gift, and it has spurred me to start collecting the stamps mentioned in this post (further cause for perdition, as if collecting oak trees were not enough!). It also led me to intensify the search for stamps that include oaks (or parts thereof, e.g., acorns, leaves, bark, etc.), and there were quite a few more that turned up. I have added a further 80 or so stamps, bringing the total to over 180. Worthy of note is what is surely the most quercine stamp, consisting of part of an oak: issued by Portugal, it is made of a wafer or cork (the bark of Q. suber). Austria also issued a stamp made of wood, cut out in the shape of an oak tree, but there is no indication that the wood used was oak. Also interesting is the series of stamps issued to commemorate Christmas by several countries in different years, all based on the Renaissance painting The Holy Family Under the Oak Tree (see Antigua and Barbuda, Benin, Grenada, New Zealand, and Uganda). I have not been able to find an explanation for the repetition.
Abkhasia
This de facto state in the South Caucasus, recognized by most countries as part of Georgia, is the only country to put Quercus fossils on their stamps: Q. kodorica and Q. sosnowskyi, both described by Georgian/Russian (Soviet) paleobotanist Alfred Alekseevich Kolakovsky (1906–1997).
Algeria
Issued as part of a series of four stamps commemorating the International Year of Forests - Fruits and Nuts (2011), this stamp bears images of Q. suber.
Antigua and Bermuda
A Christmas 2014 stamp based on The Holy Family Under the Oak Tree, a Renaissance painting said to have been completed by RedGiulio Romano (1499–1546), using a composition or underdrawing by Raphael (1483–1520); on the stamp it is attributed to Raphael. The oak in the background appears to be Q. petraea (rounded lobes, long petioles).
Argentina
Issued in 1948 to commemorate the bicentenary of postal service in Río de la Plata (River Plate). It is not clear why a twig of Q. robur is included.
Armenia
A 1995 stamp shows a red Kite (Milvus milvus) perched on a branch of Q. araxina (a synonym of Q. infectoria subsp. veneris, originally described as a variety of Q. robur found in Armenia).
Austria
A laser cut wooden stamp issued in 2017, depicting an oak of indeterminate species.
Belarus
Quercus robur (in Belarussian дуб звычайны - dub zvyčajny) is featured in this stamp issued in 2004.
Belgium
The only stamp to feature an oak cultivar, Q. 'Pondaim', a selection of the hybrid Q. dentata × pontica.
From a series on Tree Fruits and Nuts issued in 2021, this stamp features Q. robur (zomereik in Flemish and Chêne pedunculé in French).
An oak (species not specified) is featured on this stamp issued in 2009, part of a series on Forest Trees.
Benin
A Christmas 1996 stamp based on the painting The Holy Family under an Oak Tree, said to be based on a composition and first sketch by Raphael (1483–1520) and completed by Giulio Romano (1499–1546); on the stamp it is attributed to Raphael (Rafael Sanzio). Difficult to make out the oak in the stamp, but it is clear in the painting (see here), apparently Q. petraea.
Bosnia & Herzegovina
Quercus cerris (hrast cer), issued in 2013, Croatian administration, part of a series of Myths and Flora.
Quercus sessilis (a synonym of Q. petraea), issued in 2000, Croatian administration, part of a series of Flora of Bosnia and Herzegovina.
Part of a series on Old Slavic Sacred Trees, this stamp features Q, robur, identified only as Quercus (hrast).
Brazil
Issued to commemorate the Constitution of 1946, the stamp depicts a woman's head with a Phrygian cap and an oak branch, perhaps Q. robur.
Bulgaria
Quercus robur, apparently 800 years old, featured in a 1964 stamp, part of a series on trees.
Two stamps featuring species endemic to Bulgaria Q. thracica (considered a synonym of Q. cerris) and Q. mestensis (a synonym of Q. robur subsp. pedunculiflora), part of 1992 series of four Endemic Trees of Bulgaria.
Canada
Quercus rubra on a stamp issued in 1978, as part of a series featuring leaves of six Canadian trees.
Cook Islands
A Christmas 1975 stamp based on a Renaissance painting said to be completed Giulio Romano (1499–1546), using a composition or underdrawing by Raphael (1483–1520); on the stamp it is attributed to Raphael. The oak in the background appears to be Q. petraea (rounded lobes, long petioles).
Costa Rica
Issued in 1976 as part of a series commemorating the centenary of Costa Rican botanist Prof. Alberto Manuel Brenes Mora. The stamp features the rare Q. brenesii, native to Costa Rica and also found in Mexico (Veracruz) and Nicaragua; the series included four other plants named in honor of Brenes Mora. Note the epithet has been misspelled on the stamp: "Quercus brenessi Trel."
Croatia
A series of three stamps issued in 2002 featured Q.ilex (crnika), Q. petraea (kitnjak), and Q. robur (lužnjak).
Cyprus
Quercus alnifolia, the golden oak of Cyprus, featured on a stamp issued in 1994, part of a series of four trees of Cyprus. The stamp includes the local name, λατζιά, which has an interesting derivation: from Υλάτης (Hylates), an epithet attributed by the ancient Cypriots to the Greek god Apollo, Apollo Hylates, i.e., ‘Apollo who lives in the forest’, from ὕλη (hyle) = ‘forest’.
Czechia (Czech Republic)
Part of a series on Protected Trees issued in 2004, the stamp shows Žižka's Oak (Žižkův dub) in Podhradí near Lichnice, Chrudim Region, thought to be some 900 years old. The current girth and height of the tree (Q. robur) are 9.20 and over 18 m, respectively. The tree was possibly named after the famous Hussite commander Jan Žižka for its perseverance to keep standing and fight.
One of three stamps issued in a series named Protection of Nature: Trees (1993); Q. robur.
Denmark
Issued in 1999 as apart of a series featuring four deciduous trees: oak (eg), Q. robur.
Djibouti
Part of a 2022 series depicting mushrooms. This one features Daedalea quercina (oak mazegill), which frequently grows on oaks (hence the epithet), so it is safe to assume that the trees shown in the stamps are a species of oak, but difficult to determine the species.
Estonia
A stamp issued in 2008 to commemorate the 90th Anniversary of the Republic of Estonia shows a stylized Q. robur with disproportionately large leaves.
Finland
Quercus robur, issued in 1991 as part of a series on regional fruiting trees.
France
Quercus robur (chêne pedunculé), part of a series of 10 trees from around the world, issued in 2018.
A 2011 stamp depicting inhabitants of the forest, including an oak represented by a leaf (Q. robur based on the shape of the base) borne on a trunk.
A personalized stamp issued in 2011, featuring the Forest of Tronçais (see below)
A personalized stamp issued in 2010, apparently depicting an oak forest.
Oak leaves (chêne, species not specified), part of a series of eight stamps featuring tree leaves, issued in 1994.
One of a series of 10 stamps entitled "Flora", issued in 1985: Q. pedunculata (a synonym of Q. robur).
A 1976 stamp commemorating the Forest of Tronçais, a national forest comprising 10,600 hectares in the Allier department of central France. Its oaks (Q. petraea), planted by Louis XIV's minister Jean-Baptiste Colbert to supply the French Navy, constitute one of the principal stands of oaks in Europe.
German Realm (Deutsches Reich)
Issued in 1942 to commemorate Heroes Memorial Day (Heldengedenktag), the stamp shows the head of a soldier, a helmet and a sprig of oak leaves (Q. robur?).
Two 1935 stamps feature a fist brandishing an oak (Q. robur) over a swastika.
A common stamp issued by the German Realm showed a swastika in an oak wreath. Some 14 stamps of different values and colors were issued between 1934 and 1942.
Germany
Part of series of four stamps depicting the four seasons, issued in 2006. The stamp for winter features a Q. robur located in the State Domain Beberbeck near Hofgeismar, Kassel. Click here to view Eike Jablonski's photo of the oak, taken in 2018.
Issued to commemorate the opening of the National Assembly, Weimar in 1919. The image shows new shoots sprouting from an oak stump, symbolic of new government. The species appears to be Q. robur.
Issued in 1945 by Berlin and Brandenburg (Soviet Occupation zone), the stamp shows an oak seedling (probably Q. petraea) planted amid the ruins of Berlin.
Issued in 1958 to mark the 150th anniversary of the German Gymnastics Movement, the stamp features the gymnastic cross in an oak leaf.
Part of a four-stamp series of Forest Fruits, issued in 1979: Q. robur (Stieleiche).
Grenada
A stamp issued in 2000 depicts the fungus Daedalea quercina (oak mazegill) grown on the trunk of an oak.
Also issued in 2000, another stamp featuring the painting The Holy Family Under the Oak Tree by Raphael and Giulio Romano (see Antigua and Barbuda, above), which hangs in The Prado Museum in Madrid.
One of a series of 17 stamps issued in 1991, featuring paintings by Vincent Van Gogh; this stamp shows his Rocks with Oak Tree, painted in 1888.
Grenada Grenadines
Issued by the Grenadine Islands belonging to Grenada, this 1998 stamp shows a detail of Eugène Delacroix's painting Forest View with an Oak Tree.
Guernsey
An island in the English Channel off the coast of Normandy, Guernsey is part of the Bailiwick of Guernsey, a British Crown Dependency. This stamp is part of a 2011 PostEuropa issue, featuring three forest trees and their fruit. It shows a Q. robur acorn.
Issued in 1975, this stamp shows an oak tree planted in Hauteville House by Victor Hugo during his exile in Guernsey. His hope was that by the time the tree had reached maturity a United States of Europe would be a reality. Part of a series of four stamps entitled Souvenir of Victor Hugo's Exile in Guernsey (1855–1870),
Hungary
A stamp issued in 1982 issued to commemorate the 200th anniversary of the Diósgyör Paper Mill. The image shows an oak leaf and acorns and leaves of another tree (linden (Tilia)?). The mill's current logo appears to show the same motif. The oak has the acorn stalks of Q. robur, but the leaf base of Q. petraea. Might it be Q.×rosacea?
A 1976 stamp commemorating the afforestation of the millionth hectare. It shows a map of Hungary with wooded areas highlighted, and leaves of forest trees including oak (Q. petraea).
Ireland
One of a series of four stamps of trees of Ireland issued in 2006. It shows Q. petraea (dair ghaelach), Ireland's national tree.
Israel
Quercus ithaburensis (Mount Tabor oak) is featured in this stamp issued in 2018, as one of a series of three named Trees of Israel.
Quercus ithaburensis was also chosen for one of the stamps in a 1981 series named Trees of the Holy Land.
Italy
One of a series of 17 stamps issued in 1936 to commemorate two thousand years since the birth of Horace. Each of the stamps includes a quotation from the classical poet's work. This stamp depicts a Q. ilex (holm oak) and an eagle, with the inscription "duris ut ilex". The quotation is taken from Book IV of Horace's Odes. The passage from which it is taken reads:
Gens, quae cremato fortis ab Ilio
iactata Tuscis aequoribus sacra
natosque maturosque patres
pertulit Ausonias ad urbes,
duris ut ilex tonsa bipennibus
nigrae feraci frondis in Algido,
per damna, per caedes ab ipso
ducit opes animumque ferro.
It has been translated by A.S. Kline as follows:
Their race, still strong despite the burning of Troy,
brought their children, sacred icons, and aged
fathers, tossed about on Tuscan seas,
to the towns of Italy, as some oak,
rich in its dark leaves, high on Mount Algidus,
trimmed back by the double-bladed axe, draws strength
and life, despite loss and destruction,
from the very steel itself.
Issued in 1958, this stamp commemorates the 10th anniversary of the Italian Constitution. It shows an oak (Q. petraea?) with a vigorous new shoot, symbolic perhaps of a new beginning.
Japan
Stamps issued on the occasion of the National Afforestation Ceremony successively in the 22nd, 23rd, and 25th years of the Heisei period (reign of Emperor Akihito).
One of a series of five stamps issued in 2023 commemorating Land Afforestation in Iwate Prefecture. It features leaves of several trees, including a section Quercus oak.
One of five stamps issued in 2022 as part of a series entitled Land Afforestation in Shiga Prefecture. It depicts Q. acuta.
Part of the Greetings - Autumn 2022 series, a stamp featuring a fruiting twig of an oak.
Two stamps in the 2020 Autumn Motifs series feature oak leaves and acorns.
A series called Greetings - Autumn 2020 includes stamps showing eight leaves, fruits, and nuts associated with autumn. They include an oak leaf that looks likes Q. dentata, and an acorn of an unspecified species (not from Section Cyclobalanopsis). The perforations follow the contour of each figure.
A 2019 series commemorating the 70th National Tree Planting Festival at the Aichi prefecture forest park includes a stamp depicting Q. mongolica.
The 2019 Gifts from the Forest series includes two stamps featuring acorns: "Acorns and Pinecones" and "Acorns and Nuts".
Two stamps in the 2019 Autumn Greetings series feature oak-related elements: a squirrel nibbling on an acorn, and nuts including what looks like a Q. acutissima acorn.
A 2017 series of Traditional Colors includes a stamp using oak leaves of three species to represent the color ocher.
A stamp in the 2014 Letter Writing Day series features acorns and chestnuts.
A 1998 series issued to mark the International Letter Writing Week featured six paintings by Itō Jakuchū (1716–1800). One depicts a parakeet in a Japanese oak.
Jersey
Quercus robur is the subject of two stamps issued by the largest of the Channel Islands, officially the Bailiwick of Jersey. The earlier one was issued in 1997 and the second in 2011, part of a PostEuropa issue.
Jordan
One of a series of three stamps of "perennial trees" of Jordan issued in 2003. It shows Q. aegilops, considered a synonym of Q. macrolepis (for some authors, Q. ithaburensis subsp. macrolepis).
Part of a multi-country emission in 2017 featuring trees of the Mediterranean: Q. cerris.
Latvia
Issued in 2005 as one of a series of stamps depicting Nature Monuments of Latvia, this stamp shows the Kaive Oak (Kaives dižozols, the giant oak of Kaive, a Q. robur) in Sēme Parish, Tukums Municipality, Latvia. In 2014 it had a girth of 10.4 m and a height of 18 m. It is reportedly the tree with the largest girth in the Baltic States and is protected as a natural monument in Latvia.
A stamp issued in 1936 features a sprig of oak leaves (Q. petraea) and the symbol of the "White Cross Fund".
A 1932 stamp depicts a Kriwe, an ancient pagan priest in the Baltic region, telling stories under a holy oak.
Liechtenstein
One of a series of three stamps with trees issued in 1986. The species is not specified but could be Q. robur.
Another series featuring trees was issued in 2016. Again, the species in question appears to be Q. robur, though no name is given on the stamp.
Lithuania
Issued in 1920 to commemorate the opening of Lithuanian National Assembly. It features a "sacred oak", presumably Q. robur. Three stamps were issued with different values: 1, 3, and 5 auksinas (a currency used in Lithuania from 1919 to 1922).
This stamp issued in 2010 features the Stelmužė Oak (Stelmužės ąžuolas), a Q. robur which grows in the former Stelmužė Manor park by Stelmužė village, Lithuania. The oak is 3.5 m in diameter and 13 m in girth at its widest part; and 2.8 m. and 9.58 m at waist level. The oak reaches 23 m in height with only side branches remaining alive. It is believed to be over 1,000 years old.
A 2016 stamp shows a Q. robur in Ąžuolynas ("oak grove"), a public park in Lithuania's second largest city, Kaunas.
Luxembourg
Part of a series of four indigenous trees issued in 1995, this stamp shows Q. pedunculata, a synonym of Q. robur.
A 2017 series of three stamps depicting Luxembourg's Orders of Merit includes a stamp bearing the Ordre de la Couronne de Chêne (Order of the Oak Crown), which rewards outstanding civil and military services rendered by Luxembourg citizens as well as achievements of distinguished artists.
Malta, Sovereign Military Order of
Issued in 2017, the stamp features a painting found in the Basilica of Santa Maria della Quercia (St. Mary of Oak Tree) in Viterbo, Italy, painted by the early 16th century artist Monaldo Trofi, known as Il Truffeta. The name of the Madonna derives from an icon that used to hand on an oak tree in the town.
Marshall Islands
Part of a 2014 series on Trees, the stamp features an oak of indeterminate species.
Moldova
A stamp issued in 2003 bears an oak hawk-moth (Marumba quercus, or Porumbacul stejarului in Moldovian), drawn on a background of oak leaves.
The oak mushroom Boletus luridus (now Suillellus luridus), commonly known as the lurid bolete or hrib lurid in Moldavian, is shown on a 1995 stamp growing among oak leaves and acorns. It is one of a series of five stamps featuring mushrooms.
Issued in 2018 as part of a series featuring eight trees: Q. robur (stejar).
Morocco
Part of a joint emission in 2017 by several countries showing trees of the Mediterranean: Q. suber (chêne liège).
Netherlands
One of a 2017 series of two stamps showing trees in summer: Q. robur.
New Zealand
Another stamp representing a detail of Raphael and Giulio Romano's The Holy Family Under the Oak Tree. Issued for Christmas 1983, this version is more stylized than those issued by other countries.
North Korea
A series of stamps issued in 1991 commemorated sericulture (the production of raw silk by raising silkworms) and in particular Dr. Kye Ung Sang (1893 – 1967), a North Korean geneticist and expert on silkworms. One of the stamps features the Japanese Oak Silkmoth (Antheraea yamamai), whose larva mainly feed on Quercus species. Leaves and acorns of an oak are included in the stamp.
North Macedonia
One of a 1998 series of two stamps commemorating Christmas. It shows a loaf of bread and oak leaves of an unspecified species with distinctly long petioles. Both items form part of traditional Christmas ceremonies in North Macedonia, the oak in the form of the Бадник (badnik) or Yule log, which is lit on Christmas Eve.
Part of a series issued in 2001 featuring four native trees of Macedonia, two of which are oaks: Q. coccifera and Q. macedonica (a synonym of Q. trojana).
Northern Cyprus
One of a series of two stamps issued in 2011 showing "hundred-year-old trees" (the other is an Olea europea): Q. infectoria. The subspecies that is found in Cyprus is known as Q. infectoria subsp. veneris, for some authors Q. boissieri. It is difficult to make out the text on the stamp in the low-resolution image available, but it appears to say "Quercus infectoria ssp. Cyprus Oak". Cyprus oak is one of the common names of this taxon, also known as Aleppo oak, gall oak, and dyer's oak.
Poland
A stamp issued in 2013 commemorates 455 years of Polish Post. Designer Agnieszka Sancewicz chose the tree rings on the section of the trunk of an oak tree to symbolize the traditions and longevity of the institution. Also included is the outline of an oak leaf which disturbingly resembles an eastern North American species (Q. stellata? Q. macrocarpa?) rather than a species native to Poland. The stamp was voted "Most Beautiful Stamp" at the 44th International Philatelic Art Awards in Asiago (Italy) in 2014.
Poland's other native oak, Q. petraea (dąb bezszypułkowy), is the subject of a stamp issued in 1995.
One of a series of six stamps issued in 1978 showing different tree species, under the title "Protection of the Environment": Q. robur (dąb szypułkowy).
Part of a series featuring Tourist Attractions, a 1966 stamp shows old oaks at Rogalin Landscpape Park. About 2,000 magnificent oaks are found on the banks of the river Warta near Rogalin, among numerous oxbow lakes. It is Europe's largest group of monumental oak trees. Their trunks reach a circumference of up to 9 meters, and all those reaching over 2 m in circumference are protected by law.
Issued in 1964 to commemorate the 20th anniversary of the Polish People's Republic, the stamp features a stylized oak. Apparently.
The prisoner-of-war camp in Woldenberg, Poland, presently named Dobiegniewo, was the first POW camp to establish an internal postage system. The camp was named Oflag II C (Oflag - Offizier Lager- POW camp for officers only). One of their stamps issued in 1944 shows the stump of an oak, newly felled, with an axe wedged in it, with twigs of new growth sprouting behind. The image is presumably a symbol of regrowth following destruction. The leaves seem to be Q. petraea. Four stamps have the same design and different values: 10, 20, 30, and 40 German reichspfennig.
Another stamp issued in 1944 by the Woldenburg POW camp depicts the Piast Tower in Cieszyn and a spring of Q. petraea leaves and acorns.
Portugal
Quercus suber (sobreiro) is featured on one of the stamps issued in 2017 as Portugal's contribution to the multi-country emission commemorating trees of the Mediterranean (Árvores do Mediterrâneo).
In 2007 Correios de Portugal (Portuguese Postal Service) and the Portuguese Assembly of the Republic issued the world's first stamp made of cork. It was made entirely of self-adhesive cork paper, with a face value of 1 euro. It was designed by artist João Machado and celebrated the Portuguese cork sector, which has put Portugal at the forefront of world cork production and exports. The image shows a solitary Q. suber growing in an undulating landscape.
A 1977 stamp shows the trunks of Q. suber stripped for cork.
Romania
A 1983 stamp celebrates the 65th anniversary of Romanian unification. Below a tri-color ribbon in the colors of the Romanian flag, with the country's coat of arms in the middle, sits a Q. petraea twig bearing two leaves and an acorn (the oak is Romania's national tree).
To commemorate the 35th anniversary of the republic in 1982, Romania issued a stamp that shows the national flag above a fruiting twig of what appears to be Q. petraea.
One of a 1994 series of eight stamps showing trees: Q. robur.
Issued in 1956 as part of a series commemorating the Month of the Forest: Q. robur.
Russia
Issued in 2015 as one of four stamps in a series featuring trees: Q. robur (дуб черешчатый, dub chereshchatyy, "pedunculate oak").
San Marino
A 1999 series shows four examples of bonsai trees, one of them a Q. robur.
Quercus pubescens is featured in a stamp from a 1997 series of four "Monumental Trees".
One of five stamps in a Flora and Fauna series, the stamp features a garden dormouse (Eliomys quercinus) and Q. ilex.
São Tomé and Príncipe
Part of a four-stamp series of Mushrooms issued in 20187, the stamp features the mushroom Leccinum quercinum, now a synonym of L. aurantiacum (orange oak bolete). Also pictured is a red squirrel (Sciurus vulgaris) gnawing on a nut. The squirrel sits on a branch, which, based on the epithet of the mushroom and the presence of a squirrel, is most likely an oak. The mushroom is known to be associated with oak, but can also be found under poplar, aspen (Populus sp.), beech (Fagus sp.), or birch (Betula sp.).
Slovakia
One of a series of three stamps in a series issued in 1993 under the title "Protection of Nature": Q. robur.
Slovenia
Part of a series dedicated to Slovenians around the world, this 2020 stamp bears the legend "Slovenians in Germany" (Slovenci v Nemčiji) and bears stylized representations of Tilia platyphyllos (lipa) and Q. robur (hrast dob), presumably representing Germany and Slovenia.
Soviet Union
Part of a 1980 series featuring "Protected Trees and Shrubs": Q. robur (дуб обыкновенный, dub obyknovénnyy, "common oak").
Issued to commemorate the 150th birth anniversary of the painter Ivan Shishkin (1832–1898), this stamp shows his 1865 painting entitled Дуб (oak): Q. robur (probably).
One of five stamps in a 1988 series dedicated to the fountains of Petrodvorets (Петродворец), a former name for Petergof (Петерго́ф), a palace in St. Petersburg, famous for its fountains. The fountain depicted in the stamp is known as дубок (dubok), meaning "oak seedling," and is one of the so called joke-fountains, in this case in the shape of a stylized young oak, presumably Q. robur or Q. petraea.
Spain
Issued in 1966 to commemorate the 600th anniversary of the city of Guernica. The stamp features the Árbol de Guernica (in Basque Gernikako Arbola, "Tree of Guernika"), a Q. robur that symbolizes traditional freedoms for the Biscayan people, and by extension for the Basque people as a whole. It has been replaced five times since the first was planted in the 14th century, using seedlings grown from the tree's acorns. The tree depicted on the stamp was the third, re-planted in 1860, which survived the Bombing of Guernica in 1937 but had to be replaced in 2015 because of a fungus.
A 2004 stamp features the Terrona Oak (encina "La Terrona)" in Zarza de Montánchez, Extremadura. It is identified as Q. ilex on the stamp, but according to the Monumental Trees website, it is Q. rotundifolia. It is thought to be 500-700 years old and measured 17 m x 2.49 m dbh in 2016.
One of a series of two stamps issued in 2000 featuring trees: Q. ilex (encina).
Issued in 2003, in a another two-stamp series featuring trees: Q. robur (roble).
Part of five-stamp series of Flora, a stamp issued in 1972 features Q. ilex (encina).
Switzerland
Part of a four-stamp Pro Juventute ("For the Youth") series issued in 1992: Q. robur.
One of three stamps in a 2009 series showing Ancient Trees: Q. sp. (robur?).
Another tree series issued in 2021, consisting of four trees, this one an unspecified Quercus species, presumably Q. robur.
Syria
Issued to commemorate 2015 Tree Day, the stamp features an oak, without indicating a species. Difficult to tell from the image, but perhaps, based on the acorns, Q. libani?
Taiwan
Part of a set depicting "potted miniature plants", issued in 1985. According to the The Postal Universal Website of R.O.C., this one is an oak tree, but it is difficult to determine the species if so.
Uganda
Yet another stamp based on The Holy Family Under the Oak Tree by Raphael and Giulio Romano. Issued in 1993. Two other stamps in the series show details of the painting, but this is the only one that includes the oak tree.
Ukraine
One of a series of 20 stamps of trees issued over several years starting in 2012: Q. robur (дуб звичайний, dub zvychaynyy, "common oak").
United Kingdom
Issued in 1973 as part of a two-stamp issue featuring trees: Q. robur.
Issued in 1995 to commemorate the Centenary of the National Trust: an oak seedling, probably Q. petraea.
A stamp issued in 2003, showing a stylized oak in relief. The species is undefined but could be Q. petraea.
One of five stamps issued in 1995 to mark the centenary of the National Trust, it shows an oak seedling (Q. petraea) and bears the legend "Protecting Land".
Part of a 2010 series commemorating 10 famous scientists who were members of the Royal Society, celebrating 350 years of the Society. The stamp shows Alfred Russel Wallace (1823–1913), a British naturalist, best known for independently conceiving the theory of evolution through natural selection. Oak branches appear in silhouette above his face.
United States of America
Commemorating the 300th anniversary of the state of Connecticut, this 1935 stamp depicts the Charter Oak, an unusually large Q. alba growing on Wyllys Hyll in Hartford, Connecticut in the U.S., from around the 12th or 13th century until it fell during a storm in 1856. According to tradition, Connecticut's Royal Charter of 1662 was hidden within the hollow of the tree to thwart its confiscation by the English governor-general. The oak became a symbol of American independence and is commemorated on the Connecticut State Quarter. For Connecticut's tercentennial, it was depicted on a commemorative half dollar as well as on this stamp.
Quercus alba was also selected for one of a series of four stamps issued in 1978 featuring U.S. trees.
Part of a series of 13 stamps issued between 1987 and 1990 to commemorate the Bicentennial Ratification of the Constitution, one for each state that ratified the Constitution. The stamp corresponding to the state of Georgia shows an oak, and based on the Tillandsia usneoides (Spanish moss) draping from its branches, one might venture to say it is Q. virginiana (live oak).
Issued in 1964 to commemorate, a stamp depicts a lute, a horn, a music score, and branches of laurel and oak of indeterminate species.
In 1999 the U.S. Postal Service introduced stamps that could be purchased and printed via a personal computer. One of the designs used in 2008 showed oak leaves with fall colors, possibly Q. rubra.
Part of a series featuring photos of microscopic life, a Forever Stamp issued in 2023 used an image created by Jason Kirk that won first place in the Small World Photomicrography Competition sponsored by Nikon. It shows trichomes and stomata on a the leaf of a Q. virginiana (more details here).
A series ot 16 stamps issued in 2024 featured images by legendary nature photographer Ansel Adams, including his photo of a towering oak tree silhouetted by the setting sun taken as part of his Sunset City Project.
Vatican City
In 1995, Vatican City issued a series of definitive stamps highlighting the theme "European Year of Nature Conservation." This stamp depicts the Fountain of the Eagle in the Vatican Gardens with some Q. ilex in the background.
Western Sahara
This is a philatelic oddity as stamps issued by Western Sahara have been declared illegal by the postal administration of Morocco. All illegal stamps inscribed SAHARA OCC. were produced and distributed to the philatelic market by illegal stamp producing entities located in the UK and Eastern Europe. Nevertheless, one of these stamps, issued in 1992, shows leaves and catkins of Q. ilex.
Yugoslavia
Port a series of 14 stamps issued in late 1978 to commemorate New Year 1979: Q robur.
One of 20 stamps issued between 1992 and 2002 highlighting concern for the protection of nature: Q. robur (issued in 1997).
Another stamp in the same series, also issued in 1997, shows a great capricorn beetle (Cerambyx cerdo) on an oak leaf and trunk. The larvae of the beetle grow in the bark of oak trees.
Acknowledgments
I have IOS member Claudio Pedró to thank for the idea of writing about this subject. I'd also like to thank Wei Wang and Jacquiline Roberts for pointing out stamps I had missed. And thank Wei also for the stamp album and stamps to start the collection.