Document ID: chunk:federal_register_of_legislation:F2024L00408:front:0:p348
Version: federal_register_of_legislation:F2024L00408
Segment Type: other
Provision Reference: 
Character Range: 1057526–1060377

that appropriate details can be added to the manual.  Protocols to minimise the future introduction of diseases will be documented.

Full replacement of the plants is required due to the diseases being expected to be located throughout the soil profile of each bed, right down to the drainage layer.  All materials and equipment will need to be removed and/or sterilised, with careful quality assurance with regards to all replacement materials and products.

A number of the critical lessons learnt from the recent investigation will be documented in the maintenance manual:
      * ensuring appropriate irrigation timing, frequency and monitoring;
      * ensuring sufficient mulch;
      * minimising the opportunity for clay pans to form in the planter bed soil profile;
      * ensuring that soil chemistry is correctly balanced;
      * ensuring that plant spacing/clearance minimises the opportunity for diseases to flourish;
      * ensuring plant pruning is targeted to best enhance plant growth and presentation;  and
      * documentation and introduction of a long-term and orderly replacement strategy to avert future major plant failures.

The following additional observations were made as a result of the development of this heritage management plan.

Planter beds
The planter beds are made of a concrete construction with a cantilevered top surround.  It is noted that the top of the planter beds sit approximately 400 mm above the ground.  It is understood that the soil within the beds is open to the ground below.

In the planter beds with the remaining plantings from 2012, the soil profile sits at approximately 150 mm below the top of the planter bed surround.

At some stage after 2013, the dripper irrigation system was turned off because of flooding issues and perimeter micro sprays on risers were installed.

  Figure 116.  The Hebes within the planter beds with low soil level
  Source:  Amanda Evans

  Figure 117.  Dead and dying etiolated plants, depleted soil, with no mulch
  Source:  Amanda Evans

  Figure 118.  Plants very close to each other causing etiolation and lack of foliage
  Source:  Amanda Evans

  Figure 119.  Irrigation infrastructure throughout the beds
  Source:  Amanda Evans

  Figure 120.  Spray risers blocked by plants
  Source:  Amanda Evans

In the planter beds with the remaining 2012 plantings, the following was observed;
      * Most of the plants are only at 350 to 400 mm centre to centre.
      * There are dead and dying plants in the middle and around the edges of the bed.
      * Many of the plants are only 75-100 mm from the edge of the planter bed wall.
      * The water from the micro sprays cannot reach the base of most plants.
      * There is no mulch evident in most beds.
      * There is a large amount of irrigation infrastructure impeding good root growth in the