Pinetum

In the biggest part of the University of Maribor Botanical Garden, there is a collection of gymnosperms or a pinetum, in which mainly conifers grow.

Word pinetum originates from the Latin word for pine, which is one of the most widespread tree species in the Slovenian forests.

Do you know the basic facts about Slovenian forests and do you know which tree species are most commonly found in them?

According to the statistical data for the year 2016, there are 11,820.2 km2 of forests in Slovenia, which makes up 58.3% of the entire area. When it comes to the forest cover, our country is in the fourth place in the EU, right behind Sweden, Finland and Estonia (picture: Forest area in the EU-28).

Source: (https://www.economist.com/international/2017/11/30/trees-are-covering-more-of-the-land-in-rich-countries)

Image: Forest area in the EU-28, 2015.

The majority of the forests, 75%, are privately owned, 22% are state-owned and 3% are owned by municipalities. The forest estate is very fragmented and on average, it is only 2.5 ha. Thus, there are 313,000 forest estates in the country, which are owned by 461,000 forest owners (owners and co-owners). High degree of fragmentation and a large number of forest owners and co-owners worsen the professional work and optimal use of wood in the forests.

In Slovene forests deciduous trees prevail (54.6% in wood), the share of conifer trees is 45.6% and is decreasing. This can be attributed to the fact that in the past, they primarely forested with conifers, especially with spruce in monocultures. That is when problems with bark beetles and natural disasters appeared, which they have been witnessing in the last few years.

In forests, we find mostly beech trees (32.3%) and spruce (30.8%). A detailed structure of forests in 2015 is presented in the table.

Table: Structure of Slovenian forests (2015)

Tree species

Spruce tree

Fir tree

Pine trees

Larch tree

Other conifers

Beech tree

Oak trees

Noble deciduous trees

Other hard deciduous trees

Soft deciduous trees

Share (%)

30.8

7.5

5.6

1.2

0.3

32.3

7

5.2

8.4

1.7

Total

45.6%

54.6

Source: (www.zgs.si/fileadmin/zgs/main/img/PDF/LETNA.../2015_Porocilo_o_gozdovih.pdf)

Web links:

Maps (facts about the forest in Slovenia, tree species)

Pinetum planting

The collection consists of specimens of conifers of most species from all continents that thrive in Slovenian climatic conditions. Therefore, there are no representatives from the tropical world - it is too cold in the winter, and neither from the Arctic regions - it is too warm in the summer.

At the lower part where the pinetum begins, spruces grow, on the way up, there is a collection of fir trees, and in the upper part, there are exotic plants, which are non- indigenous in this country. Further on, there is a collection of junipers planted in the middle of the pinetum, and on the other side, when we go down towards the roses, there is a collection of pines./p>

The majority of the mentioned species belongs to the pine family (Pinaceae). Beside pines, we also find representatives from the family of Cupressaceae (cypress family) and Taxaceae (yew family) and one representative from the family of Ginkgoaceae and one representative from the family of Podocarpaceae (podocarp family).

More: Botanical classification of gymnosperms

Botanical classification (systematics) of plants is a living science, which changes according to newer, molecular and morphological phylogenetic scientific discoveries. The latest (current) version of the botanical classification of gymnosperms is shown below (Christenhusz, and others, 2011; Christenhusz & Byng, 2016).

 

SPERMATOPHYTES are divided into two groups: angiosperms and gymnosperms.

ANGIOSPERMS - Plants, which produce seeds within an enclosure.

GYMNOSPERMS - Plants, which have simplified, mostly monoecious flowers. Seeds are not encased within an ovary, but sit exposed on the surface of leaf-like structures called bracts.

What do the female and male inflorescences of gymnosperms look like?

A young male inflorescence (yellow) and a female cone of a larch tree (red).

Ginkgo is the only representative of the Ginkgoaceae family and is planted among conifers, even though it has leaves. This is because Ginkgo biloba is actually a relic plant species, the only representative of the Ginkgoaceae family. According to some sources, it is the original form of all gymnosperms on Earth.

The conifer with grey-blue needles is called cedar. Cedars come from Africa, but as ornamental plants, they are found all over the world. In the garden we can find two species of cedars, the Lebanon cedar and the Atlas cedar. The Himalayan cedar is no longer planted in our garden, because the (too) hot summers did not suit it. Cedars belong to the family of pine trees.

Cedars' needles grow in clusters, just like those of larch and pine tree, while the needles of spruce and fir trees grow individually.

Photos of larch, pine, spruce and fir trees.

Transformed leaves of pine and yew trees are needles, while cypress leaves are transformed into scale-like leaves.

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Junipers, which belong to the cypress family Cupressaceae, have differently transformed leaves in different life periods; in youth and on young branches, they have needles, while older plants have scales. This is called heterostyly.

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THE USAGE OF JUNIPER

Brits (who are big fans of the juniper) make gin out of juniper berries.

In Slovenia, juniper berries are used for the making of a homemade remedy, called brinjevec, which is similar to gin. In this process, juniper berries are soaked in a distillate.

A shot of brinjevec or gin?

The only proper juniper for brinjevec, gin or the spice is the common juniper (Juniperus communis). Although the common juniper grows in many places, only we, Slovenians, have come up with the idea to make brandy out of juniper's dark blue, incredibly bitter berries. We made brinjevec or brandy (distillate) from juniper berries.

Brinjevec has been produced in Slovenia for over 500 years. The production of brinjevec in Slovenia has a rich tradition, since the making of it has even been mentioned by Janez Vajkard Valvazor in the 17th century and by Marko Pohlin in the 18th century. For brinjevec, the term brinovec is also used in the old records.

Brinjevec is traditionally made in Primorska, where there are natural plantations of juniper on the Karst, therefore, the use of this brandy was quite locally limited in the past. Brinjevec was and still is consumed as a medicine more than it is and was as an alcoholic beverage. The fact that we do not drink it as we drink other distillates, but only when needed, is for two reasons:

  1. high price of the alcoholic beverage. For a litre of brinjevec, you will have to pay staggering €100, and even more in specialized stores!

The high price is related to the production method of the distillation, since the only raw material of brinjevec are juniper berries and you need at least 8 kilograms per litre!

Juniper berries harvested in appropriate ripeness (between August and November), are mashed together with water. Later, yeast and certain salts are added, so that yeasts can process it into juniper wine during the fermentation process. After the fermentation, which lasts up to four weeks, a double distillation follows. At the first distillation, they get soft brandy, which must be distilled for the second time, and then the essential oil has to be taken away. The given by-product, the essential juniper oil, is highly valued in the pharmaceutical and cosmetic industry, and the price ... it is suitable for the fact that a liter of it requires over 300 kilograms of juniper berries!

Brinjevec gets its harmonious aroma only after six months of ripening.

In 2003, we protected Kraški brinjevec as a spirit with a geographical indication.

  1. the taste of brinjevec. Brinjevec is a harsh and strong drink (45% vol. of alcohol) of a pleasant smell, but it is so bitter that the taste stays in the mouth even up to 12 hours after consumption.

Such only brinjevec - the most Slovene potion, is!

The second alcoholic beverage where we can find juniper is gin. Gin is a popular aromatized alcoholic drink in England and in the USA. The basis for this drink is grain brandy, in which juniper berries and various herbs are soaked for its taste. For a litre of gin, "only" 20 grams of juniper berries are needed.

Similar drink from fruit and grain brandies, with the addition of juniper berries and herbs, are also found in Serbia, where they have so called klekovača, and in the Netherlands, France and Germany, where they have as jenever, genever, or genièvre.

Web links:

Abies alba, the European silver fir or silver fir has dark green needles and a dense conical shape.

A fir tree is a symbol of honesty, hope and revival. If more fir trees grow together, they symbolize a strong friendship. Because of its evergreen nature and with it associated mythological symbolism of eternal or ever-emerging life, fir tree is the one that we decorate on Christmas and New Year, although we often find spruce, pine or juniper in its place.

A fir tree is a statuesque tree, which does not like the company of people that much. Before they inhabited this area, Pohorje and its surrounding was covered with fir and beech trees. However, urbanization caused the fir trees to move higher, away from the civilization. This means that fir trees poorly tolerate the urban environment and therefore, are not very common ornamental plants. Nevertheless, there are some dwarf varieties, which can be planted in the gardens.

Brinar fir tree, named after Mr Brinar who discovered and described this mutation, is another interesting tree among the fir trees. This is a fir tree that is suitable to be an ornamental plant. It is a mutation of a silver fir, found in Rakitna. This fir tree has, compared to others, a denser crown, a narrow column-like shape of the crown, grows quickly and tolerates the polluted air much better than a silver fir. As an ornamental tree, it is also sold outside the Slovenian borders.

In the Botanical garden, there are many different varieties of fir trees.

Spanish fir has dense and hard needles.

The Korean fir has, compared to the white fir, half shorter needles. The white fir tree is high and has long needles.

The white fir à https://en.wikipedia.org/wiki/Abies_concolor

The Korean fir is often an ornamental plant, because it is smaller than the white fir and has interesting purple cones.

Grand fir is the largest among the fir trees and has the most aromatic needles. If we crush them between our fingers, it smells like grapefruit.

Because pests do not like fir trees, etheric oil from their needles can be used to deter insects, the smell of citrus deters even ticks. The area around Lake Cerknica was once been known for the extraction of the essential oil from fir trees. It was a species of Abies alba, silver fir tree, which is indigenous in Slovenia. The majority of the produced essential oil was sold to Italy.

Once they bred bees on Pohorje and produced silver fir honey. Because fir trees do not have anything in their flowers to attract bees, like all angiosperms, bees do not collect pollen from silver fir trees, but rather sweet insect secretion or honeydew.

How is silver fir honey made?

On tree species, some types of beaked insects fed by sucking tree juice. In Slovenia, these are aphids, the scale insects and frosted moth-bugs. The insects have a rostrum, which they stick into the bark and because of the pressure (turgor pressure), the tree juice with organic substances flows into their mouth by itself.

Insects with the help of enzymes that they have in the digestive tract, convert sugars and proteins of the tree juice into glucose, fructose and some other types of sugars. Only a part of it (5-10%) they consumed themselves, and the remainder is secreted from the abdomen in the form of sweet drops, called honeydew.

Honeydew, which in the form of sticky drops, is found on the leaves of conifers (fir, spruce, pine and larch tree) and deciduous trees (chestnut, oak, willow, beech, lime, maple and ash tree), and on the leaves of the undergrowth. It is gathered by bees that carry it into the hive and process it into honey.

It is important to note that honeydew is not a real insect poo, since there are no digestive residues (faeces) in it, other than sugars, cardenolides (sterols) and amino acids. Honeydew is also no longer a phloemic juice, because it has been biochemically transformed and therefore, has a different structure.

Insects enrich the tree juices, finish the process in the hive and process the honeydew into the final product - forest honey or more correctly honeydew honey. And so according to which animal representative participates in the formation, we differ between the floral (a bee) and the honeydew honey (aphids and a bee). Compared to the flower honey, the honeydew one is denser, more opaque, less sweet, darker and has a different structure.

Types of Slovenian honey with a protected geographical indication are named after the botanical origin.

Silver fir honey is dark grey-brown with a green reflection. It is quite dense, opaque and does not crystallize. The aroma is very characteristic. The experts can sense the aroma of powdered milk, caramel, burnt sugar, resin, fresh conifer wood, syrup of spruce tips, smoke, black tea with milk and herbal candy.

Silver fir, as well as spruce, is very important for Slovenian beekeeping. It is considered one of the more capricious pastures in our country, but when it is in full swing, the harvest is more abundant than by any other plant.

Sources and web links:

At the top of the pinetum in the University of Maribor Botanical Garden grow giant sequoias. They are magnificent trees and extremely long-living organisms. They were planted at the end of the 19th century, in the plantation of exotic trees, which is a part of the Botanical Garden at the Institute for the Protection of Cultural Heritage, where the University of Maribor Botanical Garden began to be established. In nature, giant sequoias are much larger than in the University of Maribor Botanical Garden.

This part of the botanical garden, where giant sequoias grow, is called Ipavčevo. It is named after the former estate of Pavla Ipavec in Pivola. It is assumed that the family Ipavec, who was engaged in health, music and agriculture, lived on this estate.

Giant sequoias are one of the biggest living organisms on Earth. They are even bigger than the largest animals, blue whales. Because they do not have the same growing conditions as in the nature, they will not grow as high and their life expectancy will be shorter than in their natural habitat.

Arborists are responsible for the trees in urban plantations, city parks, public plantations and in private gardens.

The root of the word arbor originates from Latin and means a tree.

Arboriculture is a science that deals with the study, cultivation and preservation of trees in the urban environment. In Slovenia, foresters who have already learned the basics of botany and physiology of trees can be trained for arborists. Arborists must also be good at climbing, because, for a concrete assessment and maintenance, they have to climb up a tree.

The study of arboriculture in Slovenia … more

In the UM Botanical Garden, we also find coastal redwood, which is also an exotic tree and is considered the highest tree of the northern hemisphere. In the deep canyons north of San Francisco, where it grows naturally today, it can reach even 115 meters. Only eucalypti in Australia can grow this high.

The next tree we can find here is Cryptomeria, which comes from Japan. In autumn, it gets an autumn colour and its scales turn purple.

Why do conifers turn red in winter?

Some conifers (pines, junipers) change their needle colour in winter. This is a completely natural process, which occurs because of the drop of temperature and partial dryness of the needles. On the parts of plants that are more exposed to sunrays, the change is even more distinct. The colour of the needles goes from green to brownish to purple. This occurrence is similar to the change in the colour of the leaves of the deciduous trees. Chlorophyll in the leaf is decomposed and the plant does not replace it because it is preparing itself for winter. This is how the leaf gets its real colour, dries and falls off.

Source: https://newgarden.com/notes/discoloration-or-winter-damage

In the UM Botanical Garden there are also larch trees, which are the only deciduous conifers in Slovenia. Here, the bald cypress and the dawn redwood are planted. Both species have a beautiful autumn colour and are popular trees for parks.

The dawn redwood is native to Asia and the bald cypress to America. The leaves of the dawn redwood grow oppositely on the shoot, while by the bald cypress, they grow alternately.

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Under conifers grow shrubs. Due to the fall of the needles that create acidic soil reaction, under the conifers thrive acid-loving shrubs, such as alpenroses and skimmias. In the spring, they colorize the pinetum and the yellow alpenrose gives the pinetum an enticing smell. Here we also find a collection of daffodils that bloom from the end of March until the end of May.

One of the interesting tree species in the pinetum is also the yew, of which female plants are covered in red teguments. Yew trees do not have cones, but more berry-like fruits.

Yew trees belong to the family of Taxaceae. In this family there are several different genera of plants, which have in common a special form of the fruit - in fact, it is a seed with a fleshy surrounding. Thus, birds take care of spreading the seeds of the yew.

The yew is an indigenous tree species. For several years it has also been on the list of endangered plant species. It is a popular ornamental plant and the ornamental gardens and hedges in the cemeteries are responsible for the preservation of the species.

Because of its long life expectancy (for some trees it is assumed that they are over 1000 years old) and because of its toxicity, the yew was a sacred tree and a symbol of immortality for the Celts.

The yew is poisonous if we consume it, so it must not be planted near kindergartens. All parts of the plant, except for the fleshy red tegument, are poisonous. The main poison in yew is called taxin.

The yew has a reddish wood, which is also used for the making of small wooden objects. We can also use it to make bows, because the shoots bent well. Because of this characteristic, it was almost exterminated in the Middle Ages due to the production of hunting and military bows.

The yew is very popular in English gardens, and was especially widespread in the period of Victorian gardens, for which, among other things, are characteristic sheared forms from a box and yew tree.

The Celts have long paid a lot of attention to the yew trees in Great Britain and Ireland, which is still visible today, as many old yews are found alongside churches. Yew was also very important in the rituals, performed by druids of the pagan people. For the Slavs, the yew tree was a sacred tree and it protected people against spells, witches and vampires with wooden amulets.

The yew grows very slowly and therefore, is ideal for shearing, since it does not have to be shaped more than once a year.

Arborvitaes grow much quicker than yew trees. They must be cut at least twice a year. They are similar to cypresses, but the real ones grow only in the Slovene Littoral, because they are sensitive to low temperatures in the winter. Arborvitaes have smaller cones, which are elongated, and the cones of cypresses are always round and quite big, up to 3 cm in diameter.

Photos

The cypress is, because it is evergreen, a symbol of eternal life. Even in the antiquity it was a symbol of mourning, which is why we nowadays find it mostly in cemeteries. The twigs of the cypress were also used for the making of wreaths, as they adored the sculptures of the Roman god Pluto, the ruler of the underworld.

Hiba, Latin Thujopsis dolobrata, has leaves that are marked with vivid white stomatal bands below. It has always been known as an ornamental plant. Nowadays, smaller varieties are available and can be planted next to the house.

https://en.wikipedia.org/wiki/Thujopsis

True pine forests are suitable for people with frequent respiratory problems and are also recommended for asthmatics. They have healing effects if we inhale the vapours of their essential oils. Needle oil promotes blood circulation, bronchial elimination and encourages coughing. Spruce and fir also have these beneficial effects on pulmonary diseases. Pohorje is suitable for such problems.

In the past, there was even a sanatorium for tuberculosis at the premises of the Hompoš Castle, which is today the registered seat of the Faculty of Agriculture and Life Sciences. There is still a Department of Pulmonary Diseases of the University Medical Centre Maribor on the slopes of Pohorje.

In Slovenia, there are several types of pine trees in the natural forests: black, Scots and eastern white pine, in the Slovene Littoral we have a stone pine, while in the hills there are dwarf pines. All these species are indigenous in Slovenia, the most widespread is the Scots pine.

Pine nuts are seeds of the stone pine. They are produced in stone pine plantations.

Where do the pine nuts come from, these nuts of sophisticated taste?

The homeland of the stone pine (Pinus pinea L.) is the Mediterranean; Southern Europe, Israel, Lebanon and Syria. It is also spread in North Africa, the Canary Islands, southern Africa and the eastern coasts of Australia. The species has edible seeds called pine nuts, which we know from the prehistoric times, for over 6,000 years.

The stone pine is a species that belongs to the family of pine trees. The tree reaches the height of 12-25 m and has a characteristic shape of the crown. In youth, it is a bushy globe, in mid-age an umbrella canopy on a thick trunk, and, in maturity, a broad and flat crown over 8 meters in width. The bark is thick, red-brown and deeply fissured into broad vertical plates. Needles are 10-20 or even 30 cm long. The stone pine cones are broad and egg-shaped, 8-15 cm long, and in compared to other pine trees, they mature the longest, 36 months or 3 years. Seeds (pine nuts, piñones or pinoles) are light brown with a powdery black coating, 2 cm large.

Spain used to be one of the world's largest producers, but in year 2016/17 when they estimated the global production at 23,600 tons, Asian countries (North Korea, the Russian Federation, China, Pakistan and Afghanistan) were the ones to produce the most pine nuts (89%). Nevertheless, the most organized production of pine nuts in the EU is in Spain (where around 2% of the total world production is produced annually).

Before the stone pine bears cones, it passes at least 15 years, but then, it can bear them for 100 years. The tree forms cones every 2-6 years (on average every third year), and the production is carried out by gatherers climbing up the tree and collecting cones, by hand or with a special tool. The cones are picked from November to February. Each worker collects 400-600 cones per day. The cones are then dried in the sun and 100 kg of cones result in 15-22 kg of pine nuts. Before they are sold, they remove the hard outer shell, using a special machinery, which increases the price of the product even more.

The process of extracting pine nuts is slow and demanding, which is why the nuts have a relatively high price (in the EU-28 around € 20.00/kg). Pine nuts are valued for their pleasant, delicate taste, their flesh melts in the mouth. They are considered one of the sweetest kernels and have a high nutritional value. Pine nuts are rich in fats (68.4%), most of which (34%) are polyunsaturated, and monounsaturated (18.8%); relatively high is also the content of protein (13.7%), minerals (calcium, iron, phosphorus, magnesium and some microelements) and vitamins (E, B and K).

The taste of pine nuts is sophisticated and is often added both in desserts and in meat or salad dishes, but the best known dish must definitely be the pesto sauce that is made from pine nuts, olive oil, basil and parmesan. In addition, pine nuts are also appreciated as an aphrodisiac.

The stone pine is also a widespread ornamental tree, which is particularly beautiful in avenues.

https://www.conifers.org/pi/Pinus_pinea.php

https://en.wikipedia.org/wiki/Pine_nut

www.mdpi.com/1999-4907/8/10/367/pdf

https://www.nutfruit.org/files/multimedia/1510229514_1497859419_Statistical_Yearbook_2016-2017.pdf

Pines are also very important for the timber industry. Because they grow fast and are not picky about where they grow, they are important plant species for afforestation. This method of restoration of the landscape was already used in the Austro-Hungarian Empire.

How did they afforest in the past? More

Today, afforestation is the domain of the forest owner, since he/she makes decisions about the maintenance of his/her forest.

Slovenian forests consist mostly of spruce. Spruce is a fast-growing tree species that has been moved to Slovenia from northern Europe. It is great for forest stands, because it grows quickly and represents an important part of the timber industry. Unfortunately, it faces many problems in Slovenia. Its life expectancy in wet plains is quite short and also, bark beetles like it.

You can use spruce tips to make syrup, which helps with coughing, or you can use it to sweeten your tea in the winter.

How to make a spruce tip syrup?

In Slovene, there is an interesting idiom “biti vitek kot smreka”, which literally translates into “to be as slender as a spruce” and is used to describe people who are very slim.

At Pohorje, more precisely in the vicinity of Meranovo, professor Krajnčič, the founder of the UM Botanical Garden, came across a special kind of spruce with blue-green needles several years ago. According to his research, chlorophyll or a green pigment is responsible for this phenomenon. In this type of spruce, there is more chlorophyll with a blue shade.

In former Yugoslavia, the Serbian spruce was also very popular, which is also known as Pancic's spruce (Pančičeva smreka). It is narrower and the young shoots are silver-grey. In nature, it grows in forests and because it is a cross between a common spruce, its existence is at risk.

Nowadays, real Serbian spruces are rare and they are reproduced vegetatively, that is, with cuttings. You can also see some of them in the Botanical Garden.