''Rubus tricolor'' ()
is an
evergreen
In botany, an evergreen is a plant which has foliage that remains green and functional through more than one growing season. This also pertains to plants that retain their foliage only in warm climates, and contrasts with deciduous plants, which ...
prostrate shrub
A prostrate shrub is a woody plant, most of the branches of which lie upon or just above the ground, rather than being held erect as are the branches of most trees and shrubs.
Background
Prostration may occur because the supporting tissues in ste ...
, native to southwestern China. Leaves are dark green above, pale green below, and stems have red bristles. It has white flowers in summer and edible red fruit. It grows approximately high and usually forming a vigorously spreading, dense mat. In cultivation, it is mainly used as groundcover. Common names include Chinese bramble,
groundcover bramble,
creeping bramble,
Korean raspberry,
Himalayan bramble,
and groundcover raspberry.
In Chinese, it is called ("").
Description
Morphology
The growth habit is prostrate/procumbent (trailing along the ground), but also climbing.
It is usually stated to be an evergreen shrub,
but sometimes said to be semi-evergreen,
or deciduous. This is because it is normally evergreen but can shed its leaves in severe winters.
The long stems arch between 30 cm (~1 ft) and 60 cm (~2 ft) high,
although it may get higher if it grows over itself or other shrubs.
The tips root when they touch the ground.
It grows at a fast rate,
spreading up to 2 m (6 ft 6 inches) per year.
It tends to form a dense, creeping mat,
of sprawling shrubs growing into each other.
The stems are
tomentose
Trichomes (); ) are fine outgrowths or appendages on plants, algae, lichens, and certain protists. They are of diverse structure and function. Examples are hairs, glandular hairs, scales, and papillae. A covering of any kind of hair on a plant ...
, having dense yellow-brown bristles, but are not prickly.
Leaf petioles are 1.5-4 cm long, and similarly bristled, with
glandular hairs and persistent
stipule
In botany, a stipule is an outgrowth typically borne on both sides (sometimes on just one side) of the base of a leafstalk (the petiole). Stipules are considered part of the anatomy of the leaf of a typical flowering plant, although in many speci ...
s approximately 1–2 cm by 4–8 mm.
Leaves are
alternate
Alternative or alternate may refer to:
Arts, entertainment and media
* Alternative (''Kamen Rider''), a character in the Japanese TV series ''Kamen Rider Ryuki''
* ''The Alternative'' (film), a 1978 Australian television film
* ''The Alternative ...
(each leaf arises at a different node).
Leaf shape is
simple
Simple or SIMPLE may refer to:
*Simplicity, the state or quality of being simple
Arts and entertainment
* ''Simple'' (album), by Andy Yorke, 2008, and its title track
* "Simple" (Florida Georgia Line song), 2018
* "Simple", a song by Johnn ...
(undivided blade) or slightly undulate (3-5 shallow lobes), ovate to oblong, with base subrounded to cordate and apex shortly acuminate (see:
Leaf shapes
The following is a list of terms which are used to describe leaf morphology in the description and taxonomy of plants. Leaves may be simple (a single leaf blade or lamina) or compound (with several leaflets). The edge of the leaf may be regular o ...
).
More simply, leaves have a heart-shaped base and a pointed tip.
The margins of the leaf are described as unevenly coarsely sharply serrate (see:
Leaf margin
A leaf ( : leaves) is any of the principal appendages of a vascular plant stem, usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, ste ...
). Leaves are approximately 6–12 by 3–8 cm in size. On the abaxial (under) surface, the colour is yellow-grey and there are bristles, particularly on the veins which are raised. Adaxially (upper surface), the leaf is dark green, glossy and mostly glabrous (hairless) with only sparse bristles between veins.
Flowers are white, about 2.5 cm wide, solitary or in small clusters.
Fruit are
aggregate
Aggregate or aggregates may refer to:
Computing and mathematics
* collection of objects that are bound together by a root entity, otherwise known as an aggregate root. The aggregate root guarantees the consistency of changes being made within the ...
drupe
In botany, a drupe (or stone fruit) is an indehiscent fruit in which an outer fleshy part (exocarp, or skin, and mesocarp, or flesh) surrounds a single shell (the ''pit'', ''stone'', or '' pyrena'') of hardened endocarp with a seed (''kernel'') ...
lets, bright red, and subglobose (imperfectly rounded), about 1.5–1.7 cm in diameter.
File:Rubus tricolor (bourgeon).JPG, Growing tip of shoots
File:Rubus tricolor 2.jpg, Leaf (abaxial surface)
File:Rubus tricolor 3.jpg, Leaf (adaxial surface)
File:Rubus tricolor (turion).JPG, Stem. Note alternate leaf pattern
File:Rubus tricolor (face inférieure).JPG, Stem (under surface)
File:Rubus tricolor - UBC Botanical Garden - Vancouver, Canada - DSC07735.jpg, Typical growth habit, creeping dense mat
File:Rubus tricolor 4.jpg, Forest garden
Forest gardening is a low-maintenance, sustainable, plant-based food production and agroforestry system based on woodland ecosystems, incorporating fruit and nut trees, shrubs, herbs, vines and perennial vegetables which have yields directly use ...
groundcover
Taxonomy
"Discovery" of ''R. tricolor'' is credited to
Père Jean Marie Delavay
Père Jean-Marie Delavay (28 December 1834 – 31 December 1895) was a French missionary, explorer and botanist. He was perhaps the first Western explorer of the region which is now encompassed by the ''Three Parallel Rivers of Yunnan Protecte ...
, and first introduced from China to the west in 1908 by plant collector
Ernest Henry Wilson
Ernest Henry "Chinese" Wilson (15 February 1876 – 15 October 1930), better known as E. H. Wilson, was a notable British plant collector and explorer who introduced a large range of about 2000 Asian plant species to the Western culture, West; ...
.
It was provisionally
described as a species by
Wilhelm Olbers Focke Wilhelm Olbers Focke (5 April 1834, Bremen – 29 September 1922, Bremen) was a medical doctor and botanist who in 1881 published a significant work on plant breeding entitled ''Die Pflanzen-Mischlinge, Ein Beitrag zur Biologie der Gewächse'' (Th ...
in 1910.
David Prain
Sir David Prain (11 July 1857 – 16 March 1944) was a Scottish botanist who worked in India at the Calcutta Botanical Garden and went on to become Director of the Royal Botanic Gardens, Kew.
Life
Born to David Prain, a saddler, and his wife ...
formally recognized it as an accepted species in a supplement to ''
Index Kewensis
The 1893 ''Index Kewensis'' (IK), maintained by the Royal Botanic Gardens, Kew, is a publication that aims to register all botanical names for seed plants at the rank of species and genera. It later came to include names of taxonomic families and ...
'' in 1913.
''R. tricolor'' is a member of the genus ''
Rubus
''Rubus'' is a large and diverse genus of flowering plants in the rose family, Rosaceae, subfamily Rosoideae, with over 1,350 species.
Raspberries, blackberries, and dewberries are common, widely distributed members of the genus. Most of these ...
'' which contains about 250 species, including the many different species of
blackberries
The blackberry is an edible fruit produced by many species in the genus ''Rubus'' in the family Rosaceae, hybrids among these species within the subgenus ''Rubus'', and hybrids between the subgenera ''Rubus'' and ''Idaeobatus''. The taxonomy of ...
,
raspberries
The raspberry is the edible fruit of a multitude of plant species in the genus ''Rubus'' of the rose family, most of which are in the subgenus '' Idaeobatus''. The name also applies to these plants themselves. Raspberries are perennial with w ...
and
dewberries
The dewberries are a group of species in the genus ''Rubus'', section ''Rubus'', closely related to the blackberries. They are small trailing (rather than upright or high-arching) brambles with aggregate fruits, reminiscent of the raspberry, ...
. ''Rubus'' is contained within the family
Rosaceae
Rosaceae (), the rose family, is a medium-sized family of flowering plants that includes 4,828 known species in 91 genera.
The name is derived from the type genus ''Rosa''. Among the most species-rich genera are ''Alchemilla'' (270), ''Sorbus ...
(the "rose family").
''Rubus'' means "bramble" or "bramble-like" in ancient Latin, and in Botanical Latin, ''tricolor'' means "three-coloured".
Focke conferred that epithet based on the three colours of the plant: leaves green above, white below, and the red bristles of the stems and petioles.
Distribution and habitat
Distribution
The native range is
Sichuan
Sichuan (; zh, c=, labels=no, ; zh, p=Sìchuān; alternatively romanized as Szechuan or Szechwan; formerly also referred to as "West China" or "Western China" by Protestant missions) is a province in Southwest China occupying most of the ...
and
Yunnan
Yunnan , () is a landlocked Provinces of China, province in Southwest China, the southwest of the People's Republic of China. The province spans approximately and has a population of 48.3 million (as of 2018). The capital of the province is ...
provinces in southwest China.
It has been introduced into Great Britain and Ireland.
Habitat
Native habitats are steep banks, slopes, forests, thickets and mountain scrub; at an elevation between 1800 – 3600 m above sea level.
Ecology
Growth cycles
''R. tricolor'' flowers in July.
It is
hermaphrodite
In reproductive biology, a hermaphrodite () is an organism that has both kinds of reproductive organs and can produce both gametes associated with male and female sexes.
Many Taxonomy (biology), taxonomic groups of animals (mostly invertebrate ...
(has both male and female organs),
but is
self-sterile
Self-incompatibility (SI) is a general name for several genetic mechanisms that prevent self-fertilization in sexually reproducing organisms, and thus encourage outcrossing and allogamy. It is contrasted with separation of sexes among individuals ...
(one plant will not fruit by itself).
It is
insect-pollinated
Entomophily or insect pollination is a form of pollination whereby pollen of plants, especially but not only of flowering plants, is distributed by insects. Flowers pollinated by insects typically advertise themselves with bright colours, some ...
,
and the fruit ripens from mid-July to September.
The plant fruits only occasionally.
Many ''Rubus'' species rely on birds (and mammals) to eat the fruit, which contain seeds. Stomach acids scarify the hard outer shell of the seed, leaving the seed within intact. The seed is deposited in the animal droppings which helps to disperse the plant and may also act as a fertiliser (see:
seed dispersal
In Spermatophyte plants, seed dispersal is the movement, spread or transport of seeds away from the parent plant.
Plants have limited mobility and rely upon a variety of dispersal vectors to transport their seeds, including both abiotic vectors, ...
).
Pests and diseases
''R. tricolor'' is generally not troubled by pests.
Grey mould (''
Botrytis cinerea
''Botrytis cinerea'' is a necrotrophic fungus that affects many plant species, although its most notable hosts may be wine grapes. In viticulture, it is commonly known as "botrytis bunch rot"; in horticulture, it is usually called "grey mould" or ...
'') may sometimes infect it.
Honey fungus (''
Armillaria
''Armillaria'' is a genus of fungi that includes the '' A. mellea'' species known as honey fungi that live on trees and woody shrubs. It includes about 10 species formerly categorized summarily as ''A. mellea''. ''Armillarias'' are long-l ...
'') is a problem for many ''Rubus'' species.
Cultivation
''R. tricolor'' is a tough plant, easily cultivated, and low maintenance.
The species is
cold hardy
Hardiness of plants describes their ability to survive adverse growing conditions. It is usually limited to discussions of climatic adversity. Thus a plant's ability to tolerate cold, heat, drought, flooding, or wind are typically considered measur ...
to about -15°c,
meaning it can be grown in
United States hardiness (USDA) zones 6-9,
and it has a Royal Horticultural Society hardiness rating of "H5".
''R. tricolor'' will grow in well-drained soil but will tolerate moist soil as long as it is fairly well-drained.
It tolerates a variety of soils such as chalky or sandy soils, but prefers loam; and tolerates acid, neutral, or alkaline soils.
The plant grows best in partial shade but will also grow in deep shade or full sun.
It is widely used as a
groundcover
Groundcover or ground cover is any plant that grows over an area of ground. Groundcover provides protection of the topsoil from erosion and drought.
In an ecosystem, the ground cover forms the layer of vegetation below the shrub layer known as t ...
plant to suppress weeds,
and protect soil.
Since it is very vigorous,
and fast-growing it is more suited to larger areas,
and is said to be too vigorous for small gardens.
Since it is tolerant of deep shade and has edible fruit, it has been recommended by proponents of
forest gardening
Forest gardening is a low-maintenance, Sustainable gardening, sustainable, plant-based food production and agroforestry system based on woodland ecosystems, incorporating fruit and Nut (fruit), nut trees, shrubs, herbs, vines and perennial vegeta ...
as a good groundcover plant under trees.
Despite forming a dense groundcover, in the absence of a canopy layer ''R. tricolor'' will still be invaded by prolific seeding tree species such as ash (''
Fraxinus excelsior
''Fraxinus excelsior'', known as the ash, or European ash or common ash to distinguish it from other types of ash, is a flowering plant species in the olive family Oleaceae. It is native throughout mainland Europe east to the Caucasus and Albor ...
''), sycamore (''
Acer pseudoplatanus
''Acer pseudoplatanus'', known as the sycamore in the British Isles and as the sycamore maple in the United States, is a species of flowering plant in the Sapindus, soapberry and lychee family Sapindaceae. It is a large deciduous, broad-leaved ...
''), and elder (''
Sambucus nigra
''Sambucus nigra'' is a species complex of flowering plants in the family Adoxaceae native to most of Europe. Common names include elder, elderberry, black elder, European elder, European elderberry, European black elderberry and tramman (Isle ...
'').
Some advice against planting ''R. tricolor'' with any plants smaller than trees because it will tend to smother them.
Propagation is usually done by
tip layering (in July),
softwood
cuttings (in summer), or hardwood cuttings (in winter).
Division is usually done in early spring.
Seed requires
stratification
Stratification may refer to:
Mathematics
* Stratification (mathematics), any consistent assignment of numbers to predicate symbols
* Data stratification in statistics
Earth sciences
* Stable and unstable stratification
* Stratification, or str ...
to simulate exposure to cold weather and trigger germination. Some advice to sow in early autumn in a cold frame. Stored seed is sown early in the year in a cold frame. Stratification of 1 month at 3°c is carried out (if sown later than February).
‘Betty Ashburner’ (''Rubus'' x 'Betty Ashburner') is a hybrid of ''Rubus tricolor'' and ''
Rubus calycinoides
''Rubus calycinoides'' is a flowering plant in the rose family (Rosaceae) native to Asia from the Himilayas to Myanmar. It was described by Otto Kunze in 1879.
Taxonomy
The botanical name ''Rubus calycinoides'' can be misleading, as the name w ...
'', sometimes referred to as "Creeping Raspberry",
although that term is also used to refer to a few other ''Rubus'' species, including the parents of the hybrid.
Uses
The fruits are edible raw or cooked and are generally treated in the same manner as raspberries.
They are usually eaten raw because they have limited shelf life once harvested.
Fruit can also be made into jam.
A purple-blue dye can be made from the fruit.
The flowers also provide forage for bees.
Notes
References
External links
*
{{Taxonbar, from=Q3337308
tricolor
Flora of China
Edible fruits