Conifers - environmental conditions, propagation, planting

Conifers (Pinophyta or Coniferophyta ) represent a botanical division of vascular, woody, perennial plants. They are part of the group of gymnosperms, with cones that bear the seeds “unveiled”. Their specific character is that they do not lose their leaves with the arrival of the cold season (except for the larches), which is why they are also popularly called “evergreen plants”. The pinophyta division comprises 8 families, 68 genera, and over 600 species of trees and shrubs, which make up the so-called coniferous forests or boreal forests in the northern hemisphere. They are plants specific to mountain areas, with some species growing even at altitudes above 2000 m. From a decorative point of view, they are found in parks, gardens, terraces, and outdoors – most of them being affected by the conditions in the apartment.

Fir (Abies spp. )

It is a genus of conifers. Most are massive trees, size I, up to 80 m high. Fir trees differ from other conifers by the appearance of acicular leaves, these being less sharp and placed on the branch in a single plane, horizontally. Fir cones have a vertical, ascending position, being similar to candles and disintegrating at maturity. They are very long-lived trees and most are slow-growing in their youth.

Spruce (Picea spp. )

It is a genus of conifers that includes about 35 species of massive trees, size I, which can grow up to 60 m in height. The spruce has a pyramidal crown, compact, and rich, with pendulous branches at maturity. It is very similar to the fir tree but is distinguished by its needles, with 4 edges, set spirally, surrounding the entire branch. At the same time, the spruce cones grow on the branches in a descending position. Among the species of this genus, the most common are Picea abies and Picea pungens.

Picea abies (common spruce) is an indigenous species, with intense green foliage. The cones are long and have a cylindrical shape, the young ones are green or reddish, and when mature they become brown. Spruce is a common species of coniferous tree, and also the most commonly used tree as a Christmas tree.
Picea pungens (silver spruce) is a tree native to North America, where it grows to size I. It has a thick columnar crown, with needles placed radially – sharp, slightly curved, green-blue. The cones are 10 cm long and have a light brown hue.

In general, among conifers, spruces have slow growth and long longevity (up to 600 years). They are frost-resistant trees, sensitive to drought and high temperatures. Prefers high atmospheric humidity and slightly acidic soil. Tolerates abundant light, but grows optimally in partial shade.

Pinus ( Pinus spp. )

It is a genus of conifers that includes over 100 species of trees that grow, in general, of the second size. They are tall, reaching up to 80 m. Most pines have thick bark and a pyramidal crown, which becomes irregular in mature specimens. The leaves are acicular, longer than the other conifers, placed radially on the branch. The cones are pendent, grey-brown, with a variable length depending on the species.

The most common pine species are:

Pinus sylvestris (forest pine) is a native species, growing from sizes I-II. In the beginning, it has a conical crown, which becomes irregular and flattened. In mature specimens, the trunk is branchless to a considerable height. The bark has a brownish tinge, differing slightly from other species. The needles grow in pairs, they are green, with a blue hue, slightly twisted. The cones are 3-7 cm long and are asymmetrical at the base.
Pinus mugo (juniper, mountain pine) is a shrub species, of medium size (2-3 m), with strong branching starting from the base. It grows in the alpine area, at very high altitudes, up to 2300 m. The needles are dark green, they are dense, and arranged in pairs. The cones have small dimensions of 2-5 cm and are kept on the branches for several years.
Pinus cembra (Swiss pine) is a tall tree, of the second size, with a thick conical crown. The needles grow in groups of 5, are 5-9 cm long, rigid, and dark green.

In general, pines have a long longevity of 600 years; P. Mugo can live up to 300 years. The mountain pine has slow growth, compared to the forest pine, which grows fast. The pines have good resistance to frost, and the forest pine also tolerates drought conditions. Most species require a place with abundant light and aerated soil with a low acid pH. Pines do not tolerate air pollution.

The European larch (Larix decidua )

It is a coniferous tree with deciduous leaves, grows to the size of I, and has a pyramidal crown, rare. It has a graceful port, with a straight stem and long, pendulous shoots, on which bundles of needles are arranged. The leaves are small (1-3 cm), light green, and soft, in autumn they turn yellow, and fall. The cones are ovoid, 3-4 cm long, and the young ones have a reddish-purple hue. Larch has long longevity of over 600 years and grows quickly. They are frost-resistant trees, require loamy, not very moist soils, and high atmospheric humidity.

The douglas fir (Pseudotsuga menziesii)

It is a massive tree, native to eastern North America. It grows very tall, up to 100 m, with a trunk diameter of 4 m and a pyramidal crown. The needles are soft, intense green, and have two white stripes of stomata on the underside. When crushed, they give off a pleasant, characteristic odor. The cones are placed hanging on the branches, they have an ovoid-cylindrical shape; between scales, it has long bracts, with three sharp ends. Douglas fir has the fastest growth of all conifers and has a longevity of up to 600 years. Requires moderate temperatures, young specimens being sensitive to frost. It is planted in a semi-shady place, in rich, well-drained soil with good drainage.

The bald cypress (Taxodium distichum)

It is a coniferous tree with deciduous leaves, native to North America. It grows to size I, up to a height of 40 m. The crown has a pyramidal shape, it is wide and rich. The needles are soft, fine, short, and green, turning reddish in autumn. They grow on thin vines, which also fall when the cold season comes. Persistent vines have buds and scaly leaves. The cones are small, 2-3 cm, and have an ovoid shape. In the natural environment, in swampy lands, cypress roots emit stalagmite-like formations called pneumatophores, which are used for respiration.

The bald cypress has fast growth and very long longevity, of almost 6000 years. It withstands moderate temperatures, being sensitive to strong frosts. It grows optimally in sunny places, with permanent moisture in the soil, being affected by drought.

The english yew (Taxus baccata)

It is an indigenous shrub, which can grow like a tree of size III or II at maturity, forming a rounded pyramidal crown. It has irregular branches, which grow almost to ground level. The needles are flattened glossy, and deep green. They are dioecious plants, the female specimens being appreciated for the seeds covered with a fleshy, red (aryl) tissue. The whole plant contains a poisonous alkaloid for humans and animals, called taxin.

The genus Taxus includes several species and decorative varieties, of which the most common are:

Taxus cuspidata (Japanese yew) – shrub species, with broad, thicker leaves, with a light green shade.
Taxus x media (hybrid between T. baccata and T. cuspidata ) – vigorous shrub, with a pyramidal shape and long branches.

The yew prefers sunny or semi-shaded places and fertile, calcareous soils. It tolerates atmospheric pollution well, so it is suitable for planting in urban environments.