T.E.R:R.A.I.N - Taranaki Educational Resource: Research, Analysis and Information Network


Elaeagnus umbellate (Autumn olive)

Kingdom: Plantae
(unranked): Angiosperms
(unranked): Eudicots
(unranked): Rosids
Order: Rosales
Family: Elaeagnaceae
Genus: Elaeagnus
Species: E. umbellata
Binomial name: Elaeagnus umbellate
Synonyms: Elaeagnus crispa, Elaeagnus parvifolia, Elaeagnus umbellata var. parvifolia
Common names: Japanese silverberry, Umbellata oleaster, Autumn olive, Autumn elaeagnus, Spreading oleaster.

Elaeagnus umbellate is a deciduous shrub indigenous to eastern Asia and it ranges from the Himalayas eastwards to Japan. 
In New Zealand it has a great potential to become an invasive weed. In the U.S.A, Elaeagnus umbellate has become an prohibited noxious weed in several States. It out-competes and displaces native plants by creating a dense shade that hinders the growth of plants that need lots of sun. It can produce up to 200,000 seeds each year, and can spread over a variety of habitats as its nitrogen-fixing root nodules allows the plant to grow in even the most unfavourable soils. Birds are attracted to the seeds, and will scatter them throughout pastures, along roadsides, near fences and in disturbed areas. The seeds have an amazing germination rate that can reach up to 90% in receptive regions. Some vegetative propagation also occurs.

Elaeagnus umbellata grows as a shrub or small tree, typically up to 3.5 m tall, with a dense crown. It commonly bears sharp thorns in the form of spur branches. The leaves are alternate, 4–10 cm long and 2–4 cm wide, entire, but with wavy margins. The leaves are covered with minute silvery scales when they emerge early in spring, but turn greener above as the scales wear off during the summer. The leaves often have brown scales beneath. The flowers are borne in the leaf axils in clusters of 1-7. They are pale yellowish-white, fragrant, aromatic and are fused at the base with 4 petals that are pointed at the tips.
The fruit is a small round drupe 0.65 to 0.85 cm in diameter. The unripe fruit is silvery-scaled and yellow. It ripens to red, dotted with silver or brown.







  

The scaly upper surface of leaf.