Don’t Let Spanish Heath Fool You

Spanish Heath (Erica lusitanica)  is a spreading shrub that is very successful at sneakily spreading along our local roadsides and invading our bushland. It has a number of attributes that make it a very successful weed, it is able to spread by suckers as well as seed. It produces a prolific amount of seed with studies showing that a single plants can produce 9 million small dust like seeds annually (Blood 2001).

Close up of small pink and white flowers

Once sold as a cut-flower now it is invading native bushland and roadsides

Spreading unchecked along a highway roadside.

Large infestation that has spread over an embankment.

A large plant like this can produced millions of seeds a year.

The main reason it is able to prosper is that it is often mistaken for a native species, its foliage and growth habit have similarities to species such as Common Heath (Epacris impressa) which is Victoria’s floral emblem.  If in doubt about whether or not the plant is Spanish Heath, you can contact the Local Shire or Department of Environment and Primary Industries (DEPI) for assistance. (Or submit a photo to this site).

Spanish Heath can be controlled by hand pulling plants, especially seedlings, although to avoid re-growth by suckering, it is important to remove all of the roots. Alternatively larger plants can be cut off at the base and treated with a herbicide (e.g. Glyphosate) as per the instructions on the label. Although there is no chemical registered in Victoria larger infestations can also be carefully sprayed “off label: using a suitable non-restricted herbicide (see your chemical supplier for recommendations).

Avoid slashing the heath as this will most likely encourage suckering and growth of the plant   and possibly help spread the seeds. Be careful to dispose carefully of any Spanish Heath that has been removed, to avoid it spreading to new sites.

Shade Loving Weeds and Revegetation

Re-vegetation with native species can be a great way to enhance the local environment, provide habitat for local wildlife and also shade out weeds such as Blackberries and Ragwort. One thing to be aware of is that some weeds thrive in shady conditions and if left unchecked can rapidly take over and smother and kill any of your new plantings and provide no chance for other native species to naturally regenerate. Weeds that already exist in the area and that thrive under canopy shade include Blue Periwinkle (Vinca Major), Arum Lily (Zantedeschia aethiopica) and Wandering Creeper (Tradescantia fluminensis). A major priority of any project, where shady conditions exist or will be created, should be to control these weeds if they are present. If you are planning re-vegetation these weeds should be eliminated from a site before you start any planting.

Blue Periwinkle has taken over the understorey under the canopy of these trees at this site in Traralgon South.

Feral Animals

Feral Cat – Remote Camera Photo

As with most localities feral animal locally pose a threat to both the environment and agriculture. Cats and Foxes prey on birds and small reptiles and mammals, Rabbits cause erosion and damage pasture and native vegetation with their grazing. Indian mynas are aggressive birds and can displace native species from their habitat. Deer are an emerging issue and they can be very destructive, especially to wet gully areas.

Effective control is best done in an integrated and coordinated way. i.e. it is usually futile trying to destroy one pest if there is surrounding population that is not being controlled. Let everyone know what pest animals are concerning you by completing the poll below.

Pampas Grass

Pampas grass (Cortaderia species) is as distinctive grass that has escaped from gardens and other plantings and become a major threat to native vegetation. Once established, the plant is very competitive, restricting the establishment of native trees, and can become a fire hazard and harbour vermin. Pampas grass is of greatest potential weed significance to forestry operations. Pampas grass is not considered an agricultural weed, because young plants are readily grazed by stock and it shows no ability to establish in cropping systems.

Individual plants have the ability to produce vast quantities of windborne seed – up to 100,000 per flower head – which can infest areas within a 25 km radius. In many cases, garden plants are the seed source for infestations.

The method of control for pampas grass depends on the site on which it occurs and the potential risk for causing new infestations. Permanent mechanical removal is recommended wherever possible. Grubbing of plants, particularly when small, is the best method of control in urban and bushland areas. This can be difficult with large plants because of their extensive root system and the abrasive nature of the leaves.

Control of large plants is easier and more effective if any seed heads are removed first and the plant is slashed before grubbing the crown and roots. Seed heads should be placed in a plastic bag and destroyed in an appropriate way. The best conditions for grubbing are when the soil is moist so removal is easier. The crown and roots must be completely removed from contact with the soil. Suitable disposal methods for plant material are necessary to prevent re-establishment.

Use of herbicides (low-risk areas) Only a registered herbicide used according to the direction on the label should be used to control a weed.

Smaller plants (less than 40 cm) can be controlled using a wiper applicator with the recommended herbicide. For larger plants, slash the plant to reduce the foliage, taking care to dispose of any plant material in the appropriate way to prevent re-establishment, and then spray with the recommended herbicide. Alternatively, the plant can be burnt (if local conditions allow), allowed to recover, and any new growth sprayed with the recommended herbicide. Do not spray plants stressed by drought or frost, and ensure there is thorough wetting of larger plants with the herbicide. Follow-up treatment may be required if regrowth occurs. (Source NSW DPI)

Pampas Grass is a threat to native vegetation and forestry areas.

Weed Control Priorities

Where to start:

Planning to get the most efficient use of your weed control resources following a busfire is vital. Here are some tips.

1. Target species that are likely to remain a major problem even when your bushland and pastures have recovered. e.g. Blackberries and Ragwort. Annual weeds like milk thistles and capeweed should not be a significant issue down the track as they are shaded out and outcompeted by native vegetation growth or well managed pastures.
2. The first priority for best use of your time and resources should be to maintain your areas that are free of your target species or have the lowest infestations of weeds. i.e. This should mean these areas remain easy to manage and do not become a problem area in the future.
3. Working to reduce the cover of larger infestations needs to be done stratetigically. Make a plan and work away at the edges of the affected sites over time.
4. Avoid ground disturbance as much as possible as this will create ideal opportunites for further weed infestations to occur.
5. Consider planting problem sites like gullies and waterways with native vegetation that will eventually provide competition and outgrow the weeds. Seek advice from Landcare about funding opportunites for projects and for information on what species to grow.
6. Mapping the weeds you need to control (A GPS can help with this) can help when planning your weed management as well as way to monitor your progress. You could also set up photopoints to get a visual record of how your weed management is progressing.
7. Prevention is better than the cure – Monitor carefully for new outbreaks of weeds especially in places such as, stock camps, drainage lines and sites where introduced fodder has been spread.

Inkweed

Inkweed – Phytolacca octandra

A common weed that has emerged and become conspicuous since the 2009 fires are Ink-weed Phytolacca octandra. This erect, herbaceous perennial from tropical America used to be a noxious weed in Victoria. It is still considered to be a troublesome weed. It infests bare soil areas and is spread by birds colonising large areas Ink-weed can grow up to 2 metres high and has brittle spreading branches. Red coloured stems which grow from a well-developed tap-root. It has smooth bright green leaves. Greenish white flowers occur close together on upright tapered spikes between August and November. The fruits are dark purple to black berries which exude a red-purple juice. This plant can turn up in gardens and bushland unnoticed and can dominate large areas inhibiting the growth of more desirable species. Ink-weed can be grubbed out being careful to get as much of the tap-root as possible. It will also respond well to being sprayed with an appropriate herbicide. Brush Off (Metsulfron Methyl) can be effective. (Text Source from SGLN weeds website)

Phytolacca octandra – Inkweed, This clump of Inkweed has gotten away and produced hundreds of new seeds. Inkweed now chokes this small gully.

Phytolacca octandra – Inkweed, Flower
spike with newly forming berries.

Phytolacca octandra – Inkweed, This inkweed needs to be controlled now before it flowers and sets seed. If hand-pulling make sure the tap-root is removed.

Phytolacca octandra – Inkweed, Showing the shiny purple-black berries.

Variegated Thistle – An Unwanted Succesor

This site on a steep slope was severely affected by fire. The Wattle trees on it were sensitive to fire and were all killed. For some reason there has been little regeneration of native species and the main thing that grew after the fire was blackberries. The Blackberries were successfully sprayed and their cover was dramatically introduced. However the bare soil provided an ideal opportunity for this Variegated Thistle to take over and spread. Rehabilitation of this site will be a slow process. The thistles have now been sprayed and native tubestock have been planted, but a long-term follow-up weeding program will have to occur to control the thistles and blackberry and allow the native vegetation to eventually again dominate the site.

Variegated Thistle – Silybum marianum