Herbaceous plants are
vascular plants that have no persistent
woody stems above ground.
This broad category of plants includes many
perennials, and nearly all
annuals and
biennials.
Definitions of "herb" and "herbaceous"
The fourth edition of the ''
Shorter Oxford English Dictionary'' defines "herb" as:
#"A plant whose stem does not become woody and persistent (as in a tree or shrub) but remains soft and succulent, and dies (completely or down to the root) after flowering";
#"A (freq. aromatic) plant used for flavouring or scent, in medicine, etc.". (See:
Herb)
The same dictionary defines "herbaceous" as:
#"Of the nature of a herb; esp. not forming a woody stem but dying down to the root each year";
#"
BOTANY Resembling a leaf in colour or texture. Opp.
scarious
This glossary of botanical terms is a list of definitions of terms and concepts relevant to botany and plants in general. Terms of plant morphology are included here as well as at the more specific Glossary of plant morphology and Glossary o ...
".
Botanical sources differ from each other on the definition of "herb". For instance, the
Hunt Institute for Botanical Documentation
The Hunt Institute for Botanical Documentation (HIBD), dedicated as the Rachel McMasters Miller Hunt Botanical Library in 1961, is a research division of Carnegie Mellon University.
History
HIBD is named for Rachel McMasters Miller Hunt. She don ...
includes the condition "when persisting over more than one growing season, the parts of the shoot dying back seasonally".
However, some orchids, such as species of ''
Phalaenopsis'' are described in some sources (including the authoritative
Plants of the World Online) as "herbs" but with "leaves persistent or sometimes deciduous".
In the glossary of ''Flora of the Sydney Region'',
Roger Charles Carolin defines "herb" as a "plant that does not produce a woody stem", and the adjective "herbaceous" as meaning "herb-like", referring to parts of the plant that are green and soft in texture".
Description
Herbaceous plants include
graminoids,
forbs, and
ferns.
Forbs are generally defined as herbaceous broad-leafed plants,
while graminoids are plants with grass-like appearance including
true grasses, sedges, and rushes.
Herbaceous plants most often are low-growing plants, different from woody plants like trees and
shrubs, tending to have soft green stems that lack
lignification and their above-ground growth is
ephemeral and often seasonal in duration.
By contrast, non-herbaceous vascular plants are
woody plants which have stems above ground that remain alive, even during any dormant season, and grow shoots the next year from the above-ground parts – these include
trees,
shrubs,
vines and woody
bamboo
Bamboos are a diverse group of evergreen perennial flowering plants making up the subfamily Bambusoideae of the grass family Poaceae. Giant bamboos are the largest members of the grass family. The origin of the word "bamboo" is uncertain, ...
s. Banana plants are also regarded as herbaceous plants because the stem does not contain true woody tissue.
Some herbaceous plants can grow rather large, such as the genus ''
Musa
Musa may refer to:
Places
*Mūša, a river in Lithuania and Latvia
* Musa, Azerbaijan, a village in Yardymli Rayon
* Musa, Iran, a village in Ilam Province
* Musa, Chaharmahal and Bakhtiari, Iran
* Musa, Kerman, Iran
* Musa, Bukan, West Azerbaija ...
'', to which the
banana belongs.
Habit and habitat
Some relatively fast-growing herbaceous plants (especially annuals) are
pioneers, or early-successional species. Others form the main vegetation of many stable habitats, occurring for example in the ground layer of
forests, or in naturally open
habitat
In ecology, the term habitat summarises the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species habitat can be seen as the physical ...
s such as
meadow,
salt marsh or
desert. Some habitats, like
grasslands and
prairies
Prairies are ecosystems considered part of the temperate grasslands, savannas, and shrublands biome by ecologists, based on similar temperate climates, moderate rainfall, and a composition of grasses, herbs, and shrubs, rather than trees, as t ...
and
savannas,
are dominated by herbaceous plants along with aquatic environments like
ponds, streams and
lakes.
The age of some herbaceous perennial plants can be determined by
herbchronology, the analysis of annual growth rings in the secondary root
xylem.
Herbaceous plants do not produce perennializing above-ground structures using
lignin, which is a complex phenolic polymer deposited in the secondary cell wall of all vascular plants. The development of lignin during vascular plant evolution provided mechanical strength, rigidity, and hydrophobicity to secondary cell walls creating a woody stem, allowing plants to grow tall and transport water and nutrients over longer distances within the plant body. Since most woody plants are perennials with a longer life cycle because it takes more time and more resources (nutrients and water) to produce persistently living lignified woody stems, they are not as able to colonize open and dry ground as rapidly as herbs.
The surface of herbs is a catalyst for dew, which in arid climates and seasons is the main type of precipitation and is necessary for the survival of vegetation, i.e. in arid areas, herbaceous plants are a generator of precipitation and the basis of an ecosystem. Most of the water vapor that turns into dew comes from the air, not the soil or clouds. The taller the herb (
surface area
The surface area of a solid object is a measure of the total area that the surface of the object occupies. The mathematical definition of surface area in the presence of curved surfaces is considerably more involved than the definition of ...
is the main factor though), the more dew it produces, so a short cut of the herbs necessitates watering. For example, if you frequently and shortly cut the grass without watering in an arid zone, then
desertification occurs, as show
here
Types of herbaceous plants
Herbaceous plants include plants that have either an annual, biennial, or perennial life cycle. Annual herbaceous plants die completely at the end of the growing season or when they have flowered and fruited, and then new plants grow from seed. Herbaceous perennial and biennial plants may have
stems that die at the end of the growing season, but parts of the plant survive under or close to the ground from season to season (for biennials, until the next growing season, when they grow and flower again, then die).
New growth can also develop from living tissues remaining on or under the ground, including
roots, a
caudex (a thickened portion of the stem at ground level) or various types of
underground stem Underground stems are modified plant parts that derive from stem tissue but exist under the soil surface. They function as storage tissues for food and nutrients, in propagation of new clones, and in perennation (survival from one growing season to ...
s, such as
bulbs,
corms,
stolon
In biology, stolons (from Latin '' stolō'', genitive ''stolōnis'' – "branch"), also known as runners, are horizontal connections between organisms. They may be part of the organism, or of its skeleton; typically, animal stolons are external s ...
s,
rhizomes and
tuber
Tubers are a type of enlarged structure used as storage organs for nutrients in some plants. They are used for the plant's perennation (survival of the winter or dry months), to provide energy and nutrients for regrowth during the next growing ...
s. Examples of herbaceous biennials include
carrot,
parsnip and
common ragwort; herbaceous perennials include
potato
The potato is a starchy food, a tuber of the plant ''Solanum tuberosum'' and is a root vegetable native to the Americas. The plant is a perennial in the nightshade family Solanaceae.
Wild potato species can be found from the southern Uni ...
,
peony,
hosta,
mint
MiNT is Now TOS (MiNT) is a free software alternative operating system kernel for the Atari ST system and its successors. It is a multi-tasking alternative to TOS and MagiC. Together with the free system components fVDI device drivers, XaAE ...
, most
ferns and most
grasses.
References
{{Authority control
Plant morphology
Plants by habit
Plant life-forms