Asparagus fern or Sprenger’s asparagus
(Asparagus densiflorus, syn. Protasparagus aethiopicus, Asparagus aethiopicus, Asparagus sprengeri)

Asparagus_densiflorus Asparagus_densiflorus

Family: Asparagaceae

Status:

Description
A perennial groundcover plant with sprawling wiry stems to 2 metres long arising from underground rhizomes. The small flat needle-like leaves are arranged in clusters of 2-5, 15-25mm long by 2-3mm wide. Small spines may be present in the leaf axils. Tiny (3-4mm long) white to pinkish flowers are followed by bright red berries 5-8mm across.

Preferred habitat and impacts
 Asparagus fern tends to occur around towns, particularly near-coastal locations in moist shady gullies. It can cover the ground, smothering other plants and competing for soil moisture with its dense root mat.

Dispersal
 Seed is spread by birds, in water and by dumping of fruiting material. Dumping of rhizomes (wiry underground stems) will also spread this plant. The swollen underground tubers are not capable of sprouting.

Look-alikes
Climbing asparagus fern (Asparagus scandens) has similar leaves and orange berries. As the name suggests, it climbs into trees and shrubs as well as sprawling on the ground. Another climber, Asparagus plumosus, has very fine foliage and blue-black berries.

Edible asparagus (Asparagus officinalis) is sometimes found in bush around towns and farms where birds spread the fruits from gardens. It is a taller plant, to about 1.5 metres high, with a single stem or a cluster of stems arising from a rhizome. The leaves are very fine (10-25mm by 0.5-1mm), in clusters of 3-7. Fruit is a red berry 5-10mm in diameter.

Asparagus scandens

Control
These plants have a very large root system which includes the rhizome, a mass of fibrous roots and tuberous storage organs. If digging plants out, remove all of the root system only in the smallest plants, as the amount of soil disturbance involved with larger infestations would be unacceptable. When digging it is essential to remove all of the rhizome as plants can re-grow from small fragments left behind. However, it is OK to leave tubers and fibrous roots in the ground. A sharp knife or secateurs can be used for this job. Rhizomes should be disposed of carefully and not left lying in contact with the ground. If plants are fruiting at the time of treatment the fruits should also be disposed of carefully, preferably by burning or deep burial.

Applying herbicide directly to the surface of large rhizomes, after they have been exposed at the soil surface and scraped to expose the under "bark" can be effective.

Larger infestations can be carefully sprayed, avoiding spray drift onto surrounding native vegetation. When spraying, selective herbicides give better results. Spray when the plants are actively growing. Repeat treatments will probably be needed.

If large infestations are sprayed the dead root mass remaining in the soil may prevent water penetration of the soil and regeneration of native plants, and it may need to be broken up to some extent, such as with a mattock or garden fork.