Undergrowth: what is it, plants and animals

The definition of understory refers to all that variety of vegetation that grows in the areas closest to the ground , within each and every one of the forests that exist in nature. In this way, all vegetation that grows below the tops or upper regions of the trees corresponds to an understory.

It includes both young trees, herbs and shrubs, as well as seedlings (spermatophyte plant species that are in their first stage of development, that is, from when the seed begins to germinate until the first leaves of the plant appear).

Any understory area is characterized by receiving less sunlight intensity than that received by the upper areas of the forest, where the leafy crowns of high-rise trees easily capture the sun’s rays and create areas of shade / semi-shade under them. For this reason, all the plant species that make up the understory have various adaptations to be able to carry out photosynthesis in such low light conditions.

Let’s see in more detail in the next section which plants exist in the understory and their main characteristics.

The great variety of plants that make up the understory are characterized, in general, as being small species with adaptations that allow them to survive in the low light conditions that occur permanently in the understory.

In many cases, understory saplings remain low for decades, waiting for the canopy of the tallest trees to leave some space to allow “those below” to grow and reach greater height. The shrubs , on the other hand, do not usually develop further and remain in the shady undergrowth throughout their life cycle, such is the case of holly (genus Ilex) and dogwood (genus Cornus).

Among the survival strategies that understory plant species have developed, the ability to expose their leaves to the sun during the period in which deciduous trees (deciduous trees) remain without leaves in their crowns, thus allowing the plants of the understory acquire higher light doses to meet their photosynthetic needs and maintain a carbon balance throughout the rest of the year.

Some names of understory plants from around the world are:

• Barberry ( Berberis vulgaris )
• Fern ( Blechnum cordatum )
• Bitter cress (genus Cardamine)
  
• Mouse ear ( Cerastium fontanum )
• Acetosilla ( Rumex acetosella )
• Ontineta ( Veronica serpyllifolia )
• Dandelion ( Taraxacum officinale )

Depending on the region of the planet and the environmental conditions that characterize the understory, the fauna biodiversity will be made up of various species of birds, mammals, reptiles, amphibians and also a large number of invertebrates, such as insects and worms. All of them will generally have a good predisposition to the humid environment that characterizes the understory, as well as the scarcity of direct sunlight and the shelter offered by small plants.

Among the main species of understory animals we can find:

• Insectivorous birds : talégalos or megapods of the jungle (family Megapodiidae), capulineros (family Ptilogonatidae), the giant cúa ( Cuca gigas ) and giant argos ( Argusianus argus ).
• Understory mammals: wild pigs (genus Sus), anteaters (genus Myrmecophaga), armadillos (family Dasypodidae) and mice (genus Mus).
• Reptiles: lizards (Lacertidae family) and snakes such as the emerald boa ( Corallus caninus ) and the green vine ( Gonisona oxycephala ).
• Amphibians: arrowhead frog (family Dendrobatidae), golden Panama frog ( Atelopus zetecki ) and green climbing mantilla ( Mantella laevigata ).
• Insects: burying beetle (genus Nicrophorus), termites (family Termitidae), leaf-cutter ants (genus Atta), ithomiinae butterflies, and tachyinid flies.
• Worms: centipedes (Chilopoda family), earthworms (Lumbricidae family) and leeches (Hirudo genus).