Tree Friend – Native or Wild Orange, Capparis mitchellii
NATIVE ORANGE / WILD ORANGE / NATIVE POMEGRANATE (Limited formal research undertaken on woody non-commercial species that occur in low rainfall areas, so little, or no official data)
a) Average expected life of tree, in years, from sprout to death
Very slow growing and very long-lived. Specimen in Adelaide Botanical Gardens recorded as 170yrs old; specimens in northern Flinders Ranges reported to pre-date European settlement.
b) Years until trees first fruit
10+yrs suggested in gardening forums and blogs
c) Season of year when productive tree fruits
Late spring and summer commonly reported, but also as late as May. Flowers reported throughout the year.
d) Expected or average number years tree expected to fruit for
No data available. Very long lived. Fruit yield reported as 2kg per tree.
e) Country/area of origin
Endemic to mainland Australia – common, with wide distribution in NSW, Queensland, NT, but rarer in SA and WA.
f) Average annual rainfall in area of origin
Widely distributed in warm temperate, Mediterranean and semi-arid to arid regions – described as drought and frost tolerant – reported to perform best in arid areas with rainfall 150mm-250mm, but here found near watercourses and as an understorey tree – exposed specimens reported to be stunted with poorer quality fruits. The species is evergreen, requires good drainage and resents humidity.
g) Latin name of tree and family
Latin name: Capparis mitchellii Family: Capparaceae. Not related to citrus, but rather to the caper tree, Capparis spinosa.
h) Any other products, benefits, useful or interesting facts about of tree:
Valued bush-tucker food, and useful fruit/berry for drinks, desserts, and also savoury dishes like curries – juice and pulp are consumed but not seeds or rind; unique flavour and fragrance, described variously as passionfruit with kerosene aftertaste, mango, orange/mustard/honey, but also as highly astringent, rotten orange or just unpalatable – reported variations may reflect different soils and growing conditions, and suggest timing critical for harvesting and consumption;
High level nutrition, esp. Vitamin C, thiamine, antioxidants, and some minerals;
Valuable shade tree and windbreak,
Excellent habitat for native birds and insects (prickly/spiny especially when young)
Host plant for rare migratory Caper White Butterfly, Bellevois java sp which cause marked defoliation (during 3 week larval stage). However, trees reported to recover quickly and with renewed vigour. The larvae are favoured food of blue wrens and spotted bower birds,
Excellent stock fodder – leaves highly sought after by sheep, cattle and goats, despite the spines,
Useful timber for carving and engraving; has been used to produce smoker’s pipes,
Identified by CSIRO as having significant economic potential – unique flavour and fragrance sought after by perfumery, skincare and confectionary industries and demand not sated by wild harvesting,
Stunning white or cream flowers, large and showy, valued by photographers and gardeners,
Medicinal – valued by indigenous communities in central Australia,
Cultural value – part of indigenous Dreaming heritage,
Very high conservation priority in some areas according to some reports, but apparently stable in others. It survives cool burns, but not really, hot wildfires,
Possible interest as root stock for citrus
i) Height, width and shape of tree at maturity.
Tree in Adelaide Botanical Gardens: Height 19m Trunk girth 0.4m Canopy large, almost as wide as high; estimate from photograph suggests 17.6m diameter. Commonly described as growing to 10m but garden specimens to measure at 6-8m high and 4-6m wide. Those growing in woodlands/grasslands reported to reach 3-5m but much less under harsh arid conditions. Generally described as single or multi-trunked, with black, deeply fissured bark and a dense, rounded canopy. Specimens observed in photographs have bare trunks but have been exposed to browsing stock and native animals,
j) challenges or special requirements, such as needing other varieties in order to fruit
Extremely slow growing in first few years. Young plants have small leaves and usually form a tangled spiny mass, from which a central stem or stems later emerge. Before main stems develop, branches may scramble up adjacent trees, assisted by spines at the base of the leaves. Mulching and watering of benefit for garden specimens. Juveniles in the wild are frequently found growing in close association with acacia spp – ? relationship akin to that of native sandalwoods, described as semi-parasitic. Soft, fragile storage roots 5-8cm across found 1.2m below surface by farmer digging post-holes – unable to find any other reference to species’ root structure.
Caper white butterfly devour species leaves and new growth, often defoliating whole trees in their 3 week larval stage, and white cabbage moths are equally keen,
Gall wasps parasitize the seeds, but apparently do not harm the tree itself,
Propagation described variously as easy or difficult. Seed quickly loses viability if allowed to dry out – SeedsOfSA.com recommend placing on filter paper on moist sponge before sowing 1-2cm deep and incubating at Spring/Autumn conditions (alternating 22° for 12 hours and 10°for next 12 hours). Germination time 1-6 weeks. Strike as semi-hardwood cuttings,
Tolerant of a wide range of soil types, but prefers sandy, sandy loam or clay loam with a neutral pH or slightly acidic. However, found growing on rocky hillsides and limestone in wilderness areas,
Flowers can occur at any time of year, open late afternoon, and wither next day, so likely dependent on moths and other night-flying insects for pollination.