Rosewood has been planted around the world as an ornamental street tree and garden plant. It is valued as a shade tree, a source of ‘rosewood’ timber and, in some circumstances, fodder for stock. Rosewood is drought resistant, and frost and salt tolerant. These characteristics, in addition to its ability to produce many seeds and achieve high germination rates, make rosewood a serious threat to native plants.
Rosewood, is native to southern Bolivia, northern Argentina, southern Brazil, Uruguay and Paraguay. In Australia it was originally planted in the 1970s in Queensland’s suburban gardens and streets. It grows in nearly all Australian states but has become invasive in north eastern NSW and many regions of Qld.
The single greatest reason for rosewood’s spread is the propagation and planting of the tree by householders and pastoralists. It has a prolific seeding capability (up to 10,000 seeds per plant), coupled with wind and water dispersal mechanisms (when near waterways), allows it to establish widely. The winged seed may travel a substantial distance from the tree with its helicopter style movement, and the decomposed seed then spirals down into the ground to become established. In pastoral areas cattle will eat new growth and thus kill rosewood seedlings. It is not known if passage through the cattle gut assists germination, as it does in other species. The fast growth of the seedling allows it to establish quickly, up to 4 m in its first two years of growth. Rosewood does not spread vegetatively.
Rosewood is a tree growing up to 10 m in height in Australia, with a main trunk and branches forming a distinct elevated crown. It has a large canopy cover, often greater than its height, and is consequently favoured as a shade tree.
It has reddish brown fissured bark (has narrow openings or splits).
It has opposite leaves along the leaf stalk. Leaves are approximately 30–50 mm long by 12–20 mm wide, with ‘buttock-shaped’ tips.
The bright yellow flowers (up to 22 mm in diameter) occur in leaf-less racemes (an inflorescence of stalked flowers with the youngest at the top).
The distinctive winged fruit is sometimes referred to as a ‘helicopter’, due to its spinning propeller like action as it falls. The spin is created by the swollen base, which contains one to three seeds. Depending on the wind velocity and distance above the ground, rosewood seeds can be carried considerable distances away from the parent plant.
In its native range in South America the plant grows in a subtropical environment, with generally warm temperatures year round. However, rosewood grows well in most conditions, hence its naturalisation and cultivation throughout Australia.
Rosewood will survive in temperatures down to minus 6.5ºC, and is well able to resist frost conditions. It invades disturbed sites such as roadsides and creekbanks, and also grows in woodland and open grassland areas where grazing is absent.
CRC for Australian Weed Management: Trevor Armstrong (Qld DNRM), Sandy Robertson (Gatton Shire Council, Qld), Rachel McFadyen (Weeds CRC), Shane Campbell (Qld DNRM / Weeds CRC).
While rosewood has naturalised in many areas, infestations are still at manageable levels. Any new outbreaks should be reported immediately to your local council weed officer. Do not try to control rosewood without their expert assistance. Control effort that is poorly performed or not followed up can actually help spread the weed and worsen the problem.
Rosewood (Tipuana tipu) is not declared in NSW under the Noxious Weeds Act 1993.