Wednesday, August 26, 2009

Hi there,

Apologies to all for the length of time to write this:

Bitou Threat: Moving towards an abatement plan.

After Byron Shire Council's decision to halt aerial spraying of Bitou threatened coast areas, the next step is to work out a manual work program for removal of the weed.

In this process we are fortunate enough to have the documented successful methodology employed by Ellen White, for the Dirawong Reserve at Evans Head.

For the last few years there has been no aerial spraying of Bitou and a manual approach has been used with great success. There are some important points to note in regards to this on the ground experience.

The Reserve suffered after extensive aerial spraying as it also killed natives, even in supposed exclusion zones, and then from the lack of follow up. This lack of follow up exacerbated the weed issue, allowing Bitou to regenerate.

The manual approach at Evans Head breaks down into controlled stages, as required by the DECC, the funding body :

An initial identification process, to record high priority plant species, populations and ecological communities.

This is then followed by the setting up of a monitoring process, to help determine the effectiveness of the program.

The program works in three stages:

First stage: removal of Bitou and other weed species from the immediate vicinity of the high priority plant species, populations and ecological communities.

Second stage: expansion of stage one to cover a larger area of the Bitou Bush infestation at the site. Bitou Bush removal should prioritise areas containing suitable habitat for the priority species, populations and ecological communities. This stage also involves follow-up control of Bitou Bush seedlings that germinate within all previously controlled areas.

Third stage: expansion of earlier stages from the site and surrounding areas to prevent re-invasion, and continual follow-up of previously controlled areas.

At the Dirawong Reserve Ellen developed the monitoring methodology, and established monitoring plots for the following outcomes:
Response of Bitou Bush (adult and seedlings) to the control program
Response of high priority plant species, populations, ecological communities
Response of other weed species
Response of native species – plants and animals
Recruitment: seedling density over time
In relation to canopy cover
In relation to original Bitou density
In relation to distance from frontal dune

In relation to this Shire we will need to target areas of high priority, and work outwards from these.

It is also very interesting to note that:

a) Although suspected there was no loss of frontal dune height when the Bitou was removed.

b) In the Dirawong Reserve they found native species and communities were present in apparently Bitou dominated areas.

The techniques employed by Ellen and her crew are very simple. Cutting down the Bitou and leaving it scattered as a mulch, and then following up when the seedlings germinate.

I have personally used a very similar technique on Lantana in this region for the last few years, with great success, and I cant imagine a more pleasant place to work than at the coast.

It seems that the next step is to find funding to employ some qualified bush regenerators, and then we can start the process in this Shire. Once the program has been established and areas monitored we can reinvigorate the volunteer base, through training and support. We could also document the process as a record of best practice and as a future resource for other coastal communities facing this issue..

Have we been able to find out how much the Council has saved through not aerial spraying this year? As that money was already in some kind of budget perhaps the funds can be redirected?

I do hope that we can regain the momentum we achieved earlier in the year thanks to Rose.

Perhaps we should arrange a meet with Council?

Yours,

Caspar

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Caspar A R Brace
Living Systems Designs
www.livingsystemsdesigns.com