Tree Species Catalog: Leaves, Flowers, Fruits, and Seeds

In cool temperate regions, dozens of native tree species grow wild, while many more introduced trees thrive in parks, gardens, and along streets. Some, like pine or birch, form entire forests, while others, like the sessile oak, are rarer, and the European yew has disappeared from many wild habitats and is now mostly cultivated. This Tree Guide is a catalog where each species is described using a uniform format: what its leaves, flowers, fruits, seeds, bark, and buds look like, how it differs from similar species, where it grows, how long it lives, what it is used for, and famous examples of the species. The illustrations will help you identify a tree at any time of year.

Tree Catalog

The catalog is continually updated. In each card, you will find a fact table, six illustrations (the tree, leaves, flowers, fruits or seeds, bark, buds), identification features, a comparison table with similar species, and frequently asked questions.

Tree	Latin Name	Group	Origin
English Oak	Quercus robur	deciduous	native to Europe
Scots Pine	Pinus sylvestris	conifer	native to Eurasia
Silver and Downy Birch	Betula pendula, B. pubescens	deciduous	native to Eurasia
Small-leaved Linden (Lime Tree)	Tilia cordata	deciduous	native to Europe
Norway Maple	Acer platanoides	deciduous	native to Europe
Horse Chestnut	Aesculus hippocastanum	deciduous	native to the Balkans, introduced widely
Norway Spruce	Picea abies	conifer	native to Europe
European Yew	Taxus baccata	conifer	native to Europe, often cultivated
European Hornbeam	Carpinus betulus	deciduous	native to Europe
European Ash	Fraxinus excelsior	deciduous	native to Europe
Black and Grey Alder	Alnus glutinosa, A. incana	deciduous	native to Europe
Common Juniper	Juniperus communis	conifer	native to the Northern Hemisphere
European, Siberian, and Japanese Larches	Larix	deciduous conifer	native to temperate regions
Rowan (Mountain Ash)	Sorbus aucuparia	deciduous	native to Eurasia
Willows, Sallows, and Osiers	Salix	deciduous	native to temperate regions
Bird Cherry	Prunus padus	deciduous	native to Eurasia
Black, White, and Balsam Poplars	Populus	deciduous	native to the Northern Hemisphere
Eurasian Aspen	Populus tremula	deciduous	native to Eurasia
Wych Elm, European White Elm, and Field Elm	Ulmus	deciduous	native to Europe
Common Hazel	Corylus avellana	deciduous shrub or small tree	native to Europe
European Beech	Fagus sylvatica	deciduous	native to Europe
Northern White-Cedar (Arborvitae)	Thuja occidentalis	conifer	native to North America, introduced widely
European Silver, Caucasian, and Balsam Firs	Abies	conifers	native to temperate regions
Hawthorns	Crataegus	deciduous shrubs and small trees	native to the Northern Hemisphere
Ginkgo	Ginkgo biloba	deciduous gymnosperm	native to China, introduced globally
English, Manchurian, and Butternut	Juglans	deciduous	native to temperate regions
European Crab Apple and Wild Pear	Malus sylvestris, Pyrus pyraster	deciduous	native to Europe
Alder Buckthorn	Frangula alnus	deciduous shrub or small tree	native to Eurasia
Box Elder, Black Locust, Black Cherry	Acer negundo, Robinia, Prunus serotina	deciduous	invasive in many regions

Thematic Guides

• Tree Leaves: Identification Atlas – leaf types, arrangement, shapes, margins, a table of 20 common tree leaves, conifer needles, why leaves change color, and how to make a herbarium.
• Tree Seeds and Fruits – acorns, samaras, cones, nuts, and berries, when they ripen, how they are spread by wind and animals, which are edible, and how to grow a tree from seed.
• Trees in Winter – how to identify leafless trees by their silhouette, bark, buds, leaf scars, and lingering fruits.
• Invasive Trees – box elder, black locust, and black cherry: how to identify them and why they need to be managed even in urban areas.
• Birch Sap – when and how to tap sap, general rules for foraging in public forests, hole sizes, and sustainable practices.
• Oldest and Largest Trees – ancient oaks, towering larches, famous lindens, and how monumental trees are protected globally.

Common Trees in Temperate Forests

According to global forestry statistics, forests cover about 31% of the world's land area. In cool temperate and boreal regions, the total timber volume is immense, and forest stands are typically classified by their dominant tree species. A typical breakdown of dominant species in northern European and Asian forests includes:

Forest Type	Typical Share, %	Dominant Tree
Pine forests	30–40	Scots pine
Birch forests	15–25	Silver and downy birches
Spruce forests	15–25	Norway spruce
Black alder forests	5–10	Black alder
Grey alder forests	2–8	Grey alder
Aspen forests	2–8	Eurasian aspen
Oak forests	1–5	English oak
Ash forests	< 1	European ash
Others	1–5	Linden, maple, hornbeam, elms, etc.
Total	100

Thus, more than half of the forest stands in these northern regions consist of conifers—pines and spruces—while birches make up the majority of the deciduous forests. Broadleaved trees like oaks, ashes, lindens, and maples, which formed vast primeval forests thousands of years ago, today cover only a small percentage of the area, though individual trees are found everywhere. Ash forest areas have declined sharply in recent decades due to ash dieback, a fungal disease that has devastated ash populations across Europe.

The largest contiguous forests are often found in regions with sandy soils or rugged terrain less suitable for agriculture. Many of these vital forest ecosystems are now located within protected areas, national parks, or their buffer zones to preserve biodiversity.

Wild Fruit Trees, Shrubs, and Introduced Trees

In addition to the main forest canopy trees, the catalog describes less conspicuous but ecologically vital plants. The European crab apple and wild pear are wild relatives of orchard fruit trees; the wild pear is often protected due to its rarity in natural woodlands. The alder buckthorn is a shrub of damp forests whose leaves feed the caterpillars of the brimstone butterfly, and its bark has traditional medicinal uses. Among introduced trees, we describe the ginkgo, often called a "living fossil," and the English walnut, widely grown in homesteads. A separate section is dedicated to the spring tradition of tapping birch sap, complete with sustainable harvesting guidelines.

Rare and Historically Overharvested Trees

Not all native trees are abundant. The sessile oak, very similar to the English oak, has a more restricted natural range in some northern regions and is relatively rare. The European yew once grew abundantly in western European forests, but because of its incredibly strong, durable wood—used for making longbows, arrows, and weapon handles—it was heavily overharvested until the late 19th century. In many countries, it is listed as a protected or locally extinct species in the wild, and today it is mostly grown in parks, gardens, and cemeteries, often as a clipped hedge. The yew is one of the longest-living trees in Europe, and compounds extracted from it are used in the production of certain cancer medications.

Where Temperate Forests Came From

The current forests of northern Europe and North America began to form about 10,000 years ago as the last glaciers retreated. Tree species that the ice had pushed south gradually migrated back. Scientists determine what those ancient forests looked like from pollen deposited in peat bogs: about 5,000 years ago, many northern regions were dominated by alders, pines, birches, and spruces, while oaks, lindens, and elms together made up a significant portion of the canopy. The European ash arrived later from warmer southern regions. Historical records show that in the Middle Ages, European larches and yews were much more common in wild woodlands than they are today.

In total, cool temperate regions of Europe typically host around 25 to 30 native tree species, not counting the goat willow and other willows that often grow as shrubs. The main forest stands are formed by about half of these: Scots pine, Norway spruce, silver and downy birches, black alder, grey alder, Eurasian aspen, English oak, European ash, small-leaved linden, European hornbeam, and European larch.

Climate Change and the Future of Trees

As the global climate warms, the composition of forests will inevitably change. Scientists estimate that the current climate in many northern regions is already becoming suitable for more southern species, such as the European silver fir, sycamore maple, European beech, sessile oak, and large-leaved linden. Some botanists note that the beech is already spreading naturally into areas further north than its historical range. It is predicted that by the end of this century, species like the field maple, sweet chestnut, or wild cherry may become firmly established in previously cold climates. Conversely, conditions will worsen for cold-adapted trees: the Norway spruce is the most likely to retreat, as it is already increasingly suffering from droughts and outbreaks of the European spruce bark beetle.

Deciduous and Coniferous Trees

All common forest trees can primarily be divided into two groups.

Conifers belong to the gymnosperms: their seeds do not ripen inside fruits, but openly on the scales of cones. Their leaves have evolved into narrow, stiff needles or small scales covered with a layer of wax, which is why most conifers are evergreen—they replace their needles gradually over several years. The only exception among common northern conifers is the larch, which drops all its needles in autumn. Native conifers in northern Europe include the Scots pine, Norway spruce, and common juniper; the European yew was once widespread but is now rare in the wild. Parks and gardens often feature planted larches, firs, arborvitae (thujas), Douglas firs, blue spruces, and other pine species.

Deciduous trees belong to the angiosperms—flowering plants whose seeds ripen inside fruits: acorns, nuts, samaras, or berries. Their leaves are broad, and those growing in cool climates shed their leaves in autumn. There are many more species of deciduous trees: birches, alders, aspen, oak, ash, linden, maple, hornbeam, elms, rowan, bird cherry, willows, poplars, hazel, hawthorns, and others.

Feature	Conifers	Deciduous Trees
Leaves	needles or scales	broad leaves
In Winter	usually green (except larch)	leafless
Seeds	on cone scales	in fruits
Wood	softer, resinous	varies – from soft linden to hard oak
Examples	pine, spruce, larch, juniper, yew	oak, birch, linden, maple, alder

Native, Introduced, and Invasive Trees

Native trees have grown in their respective regions for thousands of years without human assistance, having migrated naturally after the last ice age. These include pine, spruce, birches, alders, aspen, oak, ash, linden, maple, hornbeam, elms, rowan, bird cherry, willows, and others.

Introduced (non-native) trees were brought in by humans, usually as ornaments for parks, homesteads, and streets. Many have grown in these regions for centuries and now feel like a natural part of the landscape: the horse chestnut, European larch, black locust, northern red oak, northern white-cedar, European beech, and eastern white pine. Some of the tallest trees in Europe are introduced species, such as towering Douglas firs or re-introduced larches.

Invasive trees are introduced species that have begun to spread on their own, outcompeting native plants. Environmental agencies maintain lists of invasive species (read more in the invasive trees section): the box elder, which takes over riverbanks and abandoned lots, and the black locust, often colloquially called acacia. It is not recommended to plant these trees, and it is worth removing saplings that sprout on their own.

What Makes Up a Tree

A tree is a perennial woody plant with one or more trunks and a branching crown. The roots anchor it and absorb water and minerals, the trunk carries water upwards and supports the canopy, and the leaves produce sugars from carbon dioxide and water during photosynthesis. A cross-section of the trunk reveals several layers: on the outside is the protective bark, beneath it is the phloem (inner bark), through which nutrients travel down from the leaves, deeper still is the thin cambium, whose cells divide to grow a new layer of wood each year, and in the center is the wood (xylem) with annual rings and the pith. It is because of the cambium that a tree thickens every year, and its age can be determined by the rings. The bark, buds, and crown shape are unique to each species, helping to identify the tree even when there are no leaves.

How to Identify a Tree

Experienced foresters can identify a tree from afar—by the shape of the crown, the color of the bark, or even the sound of the leaves rustling in the wind. For beginners, a simple sequence will help:

1. Leaves. Are they simple or compound? Arranged in pairs (opposite) or alternately? What is their shape and margin? See the tree leaf atlas for these details.
2. Bark. White peeling bark – birch; orange upper trunk – pine; deeply furrowed dark bark – old oak; smooth gray – young maple, linden, or hornbeam.
3. Flowers. In spring, many trees bloom with catkins (birches, alders, hazels, oaks, willows), while others have bright flowers (chestnut, bird cherry, rowan, linden).
4. Fruits and seeds. Acorns – oak; paired samaras – maple; spiky capsules – chestnut; cones – conifers. Read more in the seed and fruit guide.
5. Buds and winter silhouette. Clustered buds at twig ends – oak; large sticky buds – chestnut; shiny red – linden; opposite reddish – maple; opposite black – ash. Read more in the trees in winter guide.

The Tree's Year

Trees do not all bloom at the same time, so you can often tell what month it is by looking at which species are flowering. Below is a general calendar for cool temperate climates in the Northern Hemisphere; in any given year, dates may shift by a week or two depending on how early spring arrives.

Time of Year	What Happens
Late Winter to Early Spring	hazels and alders release pollen; pine and birch buds are collected; maple sap begins to flow as snow melts
Early to Mid-Spring	birch sap is tapped; willows and sallows bloom
Mid to Late Spring	birches bloom and release pollen, leaves unfurl; maples bloom
Late Spring	oaks, chestnuts, bird cherries, and rowans bloom; pines begin to release pollen
Early Summer	pines and spruces shed pollen; poplar and willow fluff flies in the wind
Mid-Summer	lindens bloom, linden blossoms are collected; birch seeds ripen
Late Summer to Early Autumn	hazel nuts and rowan berries ripen; the first birches turn yellow
Early to Mid-Autumn	acorns, chestnuts, and maple samaras fall; autumn colors peak, followed by leaf drop
Late Autumn to Winter	trees are leafless; identified by buds, bark, and silhouette; fruits linger on black alders and lindens

Oldest and Largest Trees

Some of the longest-living trees in Europe are oaks and yews. Ancient oaks, such as the famous Bowthorpe Oak in England or the Stelmužė Oak in the Baltic region, are estimated to be over 1,000 years old, with massive trunk circumferences. Every year, remarkable trees are celebrated in contests like the European Tree of the Year. The tallest trees in Europe are often introduced conifers, such as towering Douglas firs or historical plantings of European larch that can reach nearly 160 feet (49 m) in height. Read more in the oldest and largest trees section.

When and How to Plant Trees

The best time to plant trees in cool climates is autumn, from leaf drop until the ground freezes, and early spring, before the saplings leaf out. Trees planted in autumn establish their roots over the winter and start growing earlier in the spring. Container-grown saplings with an intact root ball can be planted almost all season long, provided they are watered regularly.

• Choose the right species for the site. Pine likes light sandy soil and sun, oak prefers deep fertile loam, black alder and willows thrive in damp spots, linden and maple tolerate partial shade.
• Consider the final size. The crown of an oak, linden, or maple can reach 65–100 feet (20–30 m) wide after a few decades. Plant large trees well away from buildings, utility lines, and property boundaries.
• Dig a wide, not deep, hole. The root collar must remain at the soil surface level; a tree planted too deeply will struggle.
• Water and mulch. For the first two years, a tree needs water most of all, and mulch around the trunk retains moisture and suppresses weeds.
• Protect them. The bark of young saplings is favored by hares and mice, and the shoots by deer, so use protective tubes or fencing.

When choosing a tree for your property, give preference to native species: they are best adapted to the local climate and support native insects and birds. Invasive species—like the box elder and black locust—should be avoided.

Trees and Allergies

Many trees are wind-pollinated and release billions of pollen grains. In northern climates, the spring allergy season begins with hazels and alders, often as early as late winter, and peaks in mid-spring when birches release their pollen—birch pollen is considered one of the most significant allergens in northern regions. Later, oaks release pollen, and by early summer, pines produce so much pollen that it forms a visible yellow dust on water and cars. Allergy sufferers should monitor pollen forecasts and avoid planting highly allergenic trees near their homes.

Trees in Culture and Mythology

For ancient European peoples, trees were living entities with souls. Old oaks growing in sacred groves were considered the dwellings of the gods and were closely associated with thunder deities like Thor, Jupiter, or the Baltic Perkūnas. The linden tree was often associated with the feminine principle and fertility in various folklore traditions. In many fairy tales and myths across the continent, humans are transformed into trees—sons into strong oaks or ashes, and daughters into trembling aspens or spruces. The names of many trees in English and other Indo-European languages share deep ancient roots that reflect our ancestors' close relationship with the forest.

Benefits of Trees and Timber

Trees produce oxygen, absorb carbon dioxide, filter dust and noise, cool cities on hot days, protect soil from erosion, and provide homes for countless birds, insects, fungi, and mammals. In the forestry industry, the timber of pine, spruce, and birch is essential for construction, furniture, paper, and fuel. Each species has its own value: oak is hard and durable, perfect for parquet floors and fine furniture; linden is soft and white, ideal for carving; maple is prized for musical instruments; and birch is a primary source of plywood and high-heat firewood.

How to Use This Guide

If you know the name of the tree, simply open its card in the catalog table. If you don't know it, start with the leaf atlas or the seed guide and narrow down your search based on its features. All species cards are structured in the same way, making them easy to compare. The illustrations are AI-generated and carefully checked against botanical descriptions of the species, while real photographs are credited with the author and license. You will find more updates about forests in our forestry section.