POPULUS ALBA: CHARACTERISTICS, HABITAT, PROPERTIES, VARIETIES - BIOLOGY - 2025

Populus alba is an arboreal species belonging to the Salicaceae family. It is commonly known as poplar, white poplar, zurzuria, white poplar, choupo, white poplar, and in English as silver poplar, abele and white poplar.

It is a whitish-looking deciduous tree, upright, measuring about 25 cm in height. Both the bark and its branches and the underside of the leaves are covered with a dense white pubescence. It has a very strong root system.

Populus alba tree. Source: pixabay.com

It is a dioecious species whose flowers hang or hang from the branches in catkins. The seeds are covered by a kind of cotton, which favors their dispersion by the action of the wind.

The white poplar is a very showy species and used as an ornamental. It has a fine wood that is used for light carpentry. As an interesting fact, Leonardo da Vinci's painting "La Gioconda" was made on a panel of Populus alba.

From an ecological point of view, it is a species that is used to recover riparian areas, and can be used as a bioindicator of contamination of some elements such as cadmium, zinc and arsenic.

As for its healing properties, white poplar is used to heal wounds or sores formed during hospitalizations.

characteristics

White bark of poplar. Source: pixabay.com

Tree

The Populus alba represents a deciduous tree that grows to about 25 m, its size varies and has a straight and sinuous stem. They have a columnar bearing and a very narrow crown.

The bark of this tree is whitish or greenish-white in appearance and has black scars. It is cracked and becomes darker in older individuals.

It has fine twigs covered by a great deal of dense white pubescence, and they become glabrous in late summer. It has a very strong root system.

Leaves

The leaves of the poplar are alternate, petiolate, with a green upper surface, while the underside is covered by white clothing. In particular, this tree has a variable foliar morphology; they can be serrated-angular or webbed-lobed. The margin is smooth, or it may also have rounded teeth with spaces between them.

Male flowers of Populus alba. Source: No machine-readable author provided. Rob Hille assumed (based on copyright claims).

flowers

The poplar is a dioecious species, it presents its unisexual flowers located along catkins. The male flowers are elongated and hanging, they have a hairy appearance, bract samples and red anthers. For its part, the female flowers are greenish.

Flowering occurs before new leaves emerge.

Fruit

The fruit of this tree is a capsule, and the seeds show white trichomes and cottony texture, which favors the action of the wind for their dispersion.

Taxonomy

The name of the genus Populus is the scientific name for poplars and poplars, and means “town” or specifically “town tree”. Meanwhile, the name alba, refers to the whitish or silver color of the underside of the leaves.

-Kingdom: Plantae.

-Filo: Tracheophyta.

-Class: Magnoliopsida.

-Subclass: Magnoliidae.

-Superorden: Rosanae.

-Order: Malpighiales.

-Family: Salicaceae.

-Gender: Populus.

-Species: Populus alba L.

It has as a synonym Populus major Mill. It can be crossed with Populus tremula and form a hybrid called P. x canescens. An important variety is the one frequently seen in parks, along roads and highways (P. alba L. var. Pyramidalis = P. bolleana).

Habitat and distribution

White poplar foliage. Source: pixabay.com

The poplar is distributed by the south and center of the European continent, west of Asia and north of Africa. However, it is a species considered native to the Iberian Peninsula and in the Balearic Islands it is considered an introduced species.

Specifically, this arboreal species is present in Bolivia, Canada, China, Costa Rica, El Salvador, Guatemala, Honduras, Mexico, South Africa and the United States.

Regarding the soil, Populus alba grows on various types of soil, but requires permanent moisture. They particularly grow well on calcareous soils and do not grow on saline soils.

The white poplar lives associated with river systems, springs and forms forests that are mixed with different riverine species.

Healing properties

The white poplar has some healing properties such as the healing of sores produced during hospitalization processes, or also to heal less serious wounds.

For this, the decoction of its leaves or, failing that, the decoction of the bark is used. These wounds are then frequently washed with such a decoction.

Applications

Populus alba is used for various purposes such as to make boxes and packaging, boards, pulp and plywood. The bark is not good for firewood or charcoal. The wood of the white poplar is used in light carpentry and to make panels.

Thanks to its slender bearing, this species is considered ornamental. It is widely used for garden decoration. It is frequently used as a fence in marine areas as it resists the influence of the sea.

Detail of the bark of the white poplar. Source: Crusier

Its ecological use is of utmost importance, since it is a species that is widely used to restore riparian vegetation in areas with a Mediterranean climate.

It is used as a bioindicator and, therefore, it is able to resist environmental contamination. In this sense, the white poplar tree has been tested as a bioaccumulator of trace elements in soils contaminated with cadmium (Cd), zinc (Zn) and arsenic (As).

The result of this bioaccumulation is that the leaves of Populus alba serve as phytoaccumulators of these elements mentioned, since it has been confirmed that there is a positive correlation between the content of Cd, Zn and As, and their content in the soil.

Care

- temperature

White poplar withstands minimum temperatures down to -17 ° C. On the other hand, it also supports high temperatures without problems for its development.

- Denial

This arboreal species can withstand certain conditions of waterlogging, such as the water that remains on the ground after heavy precipitation, or with the water that remains after water movements on the coasts. In fact, the poplar often lives on the banks of rivers, springs or the sea.

However, if this species is grown in areas far from natural water sources, it is necessary that during times or times of year when the temperature is high, it is watered up to four times a week.

- Location

It is essential when planting the white poplar to choose a site where in the future there will be no problems for the root development of this tree.

The main thing is to locate the seedlings of this species in a large area and away from buildings or other plant species. This is due to the strong root system they develop, which in the future can affect pipes and even break pavement or sidewalks.

On the other hand, they should also be away from other species, since the poplar is a leafy species with a rounded shape, which is why it needs ample space to develop.

Regarding light conditions, Populus alba requires direct sunlight so that its optimal growth is not affected.

- Floor

The white poplar, as it is also known, has a wide range in terms of the soil conditions in which it grows. It develops from sandy soils (beach or coasts) to poor soils with a calcareous essence.

As already mentioned, the important thing is that the soil has good moisture retention capacity. However, it grows best in cool soils, with a large amount of organic matter and of course those that are kept moist.

- Fertilization

Although the poplar is a tree resistant to poor soils, it is worth applying fertilizer a few times (two or three per year). For this, it is advisable to preferably use organic fertilizers, such as compost.

- Pruning

For pruning, although they are not necessary for maintenance, you can remove dry or damaged branches that are still attached to the tree. Severe pruning should not be done on this species.

In the event that allergy sufferers live near the tree, it is advisable to carry out intense pruning to reduce the number of flowers. This pruning should be done at the end of the winter season.

- Spread

Multiplication of Populus alba can be done by various methods. Among them, the most used are from seeds, cuttings and shoots.

By seeds

For its cultivation from seeds it is recommended:

- Keep the seeds in a container moistened with water (wet bed with a paper soaked in water).

- Transfer them to the substrate and cover them with a mineral substance, which can be the substrate itself.

- Then, these seeds should be kept in low temperature conditions (refrigerator) for a few months. It is important that during this time, the container containing the seeds is aerated.

- After this time, the seeds should be transferred to pots or bags and covered with a commercial substrate combined with perlite.

- Subsequently, the pot or bag should be placed in the sun and watered with plenty of water.

By cuttings

From cuttings, although it is a simple procedure, the following is recommended:

- At the end of winter, a woody branch should be cut, with a healthy aspect and a length of at least 40 cm. It is cut diagonally or bevel, never straight.

- Then the base of the freshly cut area is moistened, and it is impregnated with hormones to induce the production of roots.

- Afterwards, the segment or cutting must be placed in a pot containing commercial growing substrate (purchased at any nursery).

- Next, the substrate is watered and, unlike multiplication by seeds, in this case it must be placed in semi-shady conditions, approximately for 3 months while the roots are produced in the cutting.

By sprouts

Also, for its propagation from shoots, the following must be taken into account:

- When the poplar is already in an adult state, the new stems or shoots should be removed from the mother plant by making three trenches around the shoots, taking into account a depth of about 30 cm.

- Next, with the help of a shovel, a kind of lever is made so that the shoots are separated from the main trunk and from the earth.

- Subsequently, the loose shoots should be sown in pots with substrate or with the same soil of origin, in semi-shady conditions, until the shoot begins to develop. This process may take 15 days.

Diseases and pests

- Main disease

The most common disease affecting Populus alba is powdery mildew. It is also known as gray mold because it is produced by a fungus that covers the leaves, producing an appearance similar to ash. For its treatment, it is recommended to use a systemic fungicide.

- Pests

White fly

It is a small, white flying insect. Its function is to adhere to the underside of the leaves and feed on the sap. When the poplar is infested by the whitefly, it turns yellow and loses its leaves.

To avoid the attack of this pest, it is recommended to plant around some aromatic species that function as repellants.

Poplar borer

It is a beetle, but with a shape similar to a cricket. Adult perforator individuals cause pitting on young shoots and produce necrosis; whereas, the larvae form galleries in the internal part of the trunk, and cause the commercial loss of the wood. To combat this pest, specific insecticides must be applied.

Lepidosaphes ulmi

It is a hemiptera insect whose food is the sap of the poplar. The infection of this insect causes injection of toxins into the tree.

In the event of a severe attack, total decay of the tree can occur. The prevention of this pest (mealybug) is recommended with the use of biological controllers such as Aphytis mytilaspidis (hymenoptera), which parasitizes this insect.

Varieties

About five varieties of white poplar are known. Namely:

- Populus alba nivea, which has a white color on the underside of the leaves.

- Populus alba var. globosa, it is a wide variety.

- Populus alba var. bolleana, this tree has a narrower and more stylized crown.

- Populus alba pendula, is a striking tree whose set of leaves or foliage is hanging.

- Populus alba pyramidalis, is the poplar tree that has a columnar bearing and conical shape similar to a pyramid.

References

1. Madejón, P., Marañón, T., Murillo, J., Robinson, B. 2004. White poplar (Populus alba) as a biomonitor of trace elements in contaminated riparian forest. Environmental Pollution 132: 145-155.
2. Iberian trees. 2013. Populus alba L. Taken from: arbolesibericos.es
3. Catalog of Life: 2019 Annual Checklist. Species details: Populus alba L. Taken from: catalogueoflife.org
4. Tropics 2019. Populus alba L. Taken from: tropicos.org
5. Arbolapp. 2019. Populus alba white poplar. Taken from: arbolapp.es
6. The pretty Garden. (2000-2017). White Poplar- Populus alba. Taken from: eljardinbonito.es
7. CABI. 2018. Invasive Species Compendium. Taken from: cabi.org
8. All Husqvarna. 2019. All you need to know about the white poplar, one of the most resistant species. Taken from: todohusqvarna.com
9. Medicinal herbs. 2018. White Poplar. Taken from: herbsmedicinales.com.ar