Monday, 5 September 2011

Bird Habitat Clusters Constructed and Planted

In July this year we entered a Management Agreement with the Lachlan Catchment Management Authority to establish ten 10 by 10 metre bird habitat ‘clusters’ spread across 7 paddocks located to the north and east of the farm. Each is to contain trees and shrubs, and collectively they are designed to act as ‘stepping stones’ allowing native birds to move more safely across the broader landscape. Funding toward the fencing and planting comes ultimately from the Federal Government’s “Caring for Our Country” initiative.

Once the Management Agreement was signed we set about putting in all the posts and strainers at each cluster location. To make this easier we made up a template out of baling twine that would allow us to easily locate where the posts should go and ensure each was in fact square and 10 metres by 10 metres. For the fans of algebra we used the formula for triangles of A2 X B2 = C2, and physically tied knots in the twine at 5 metre intervals for two sides (each 10 metres long) then a gap of 14.14 metres for the hypotenuse.
In the photograph above you can see the final / standard layout of the posts and stays at each site.
Here you can see the stay arrangement we used. These are specifically designed to be ‘temporary’ and were manufactured for us by M A Steel at Young. The original design was from David Marsh at Boorowa who uses them for temporary electric fencing.

You can see in the above photograph that top of the stay is slipped over a star post and attached with wire. The base is anchored using another star post, visible in the second photo above/

One component of the project involved ornithologist Tony Saunders calling to assess the property for birdlife potential and to share his knowledge. When it came time to select the species to plant we sought his additional input as we wanted to make sure we maximised the value to our local birdlife from the exercise. Here is a selection of his comments … which of course we found most helpful:
  • "Go with the 3 trees and 10 shrubs for each 10m x 10m cluster.
  • Make each cluster planting as random as possible. This will put some shrubs in shade and others in full sun, as well as provide some clusters with scattered shrubs while others will have a patch of dense shrubs.  Make them as different as possible.  It would be interesting to monitor the clusters through time and see how effective they become for wildlife.
  • I suggest a mixture of shrubs from the approved list for your area.  The shrubs should be predominantly Acacias, but the species should not aim for equal numbers of each.  In natural areas there is generally a dominant species followed by lesser numbers of subordinate shrub species, so I suggest planting the 10 shrubs in a ratio of 4:3:2:1.  The actual species can be selected from the list to match the closest existing similar patch to the cluster.
  • Based on the location of the proposed clusters and what I recall from the location of existing tree species, I suggest that the tree species should be as follows: Front, Saddle, Duck Dam and Yabby Dam -  2 Grey Box and 1 Yellow Box per cluster; Yellow Box  -  3 Yellow Box per cluster; Crater and Plateau  -  2 White Box and 1 White Cypress Pine per cluster

The shrubs within each cluster should provide some passage habitat for small birds, and the White Cypress Pine/Gum mix will provide for the Grey-crowned Babbler.  The clusters are probably too small to provide sufficient resources for residency by small birds.  Glossy Black Cockatoo prefer large, dense patches of Allocasuarina species, and I doubt that they will find much use for the suggested clusters."

Armed with the above information we set off to acquire what plants we could. It eventuated that we could not source two species of shrub, Silver Casia and Angular Hopbush, so we substituted these for Wedge Leaf Hopbush. Suppliers were Gum Tree Nursery at Young and Oz Plants at Cowra.

Another important aspect was how best to actually do the planting and what materials and treatment to apply. Matt Kilby from Global Land Repair was who we went to for advice and supplies. Here’s a summary of the planting process we used:
  • Dig a hole about 400 mm deep and 30 cm across
  • Create some bull swales out both sides from the hole which will channel runoff into it when it rains in the future.
  • Mix a cup of tree starter into the loose soil that will go back in the hole when planting the tree.
  • Have a mix of tonic in a bucket. Soak the plants whilst still in the tube in the tonic mix to ensure the soil in the plant tube is completely hydrated.
  • Remove the plant from the tube and spread a heaped tablespoon of the soil mycorrhiza around the soil covering the tree roots and at the base.
  • Plant the tree in the hole with the base of the tree below natural ground level. Make the remaining hole ‘cone’ shaped so that water will run in it naturally and large enough to hold about 10 litres of water.
  • Make a hole in the centre of the mulch mat that will end up being where the tree stem comes through. Place the mat in the cone shaped hole around the base of the tree. The pre-cut bits of the mat should thus overlap slightly.
  • Place the tree guard over the tree and drive in the stake.
  • Pour about 5 litres of mixed tonic at the base of the tree.

We recently finished all of the work. The biggest unexpected learning from doing the planting was seeing the diversity of soil types and profiles when digging the holes for the plants, down to about 30-40 cm. They range from heavy clay, to sandy loam, to coarse 'breaking down' granite.

What follows are photographs of each of the clusters by paddock name and cluster location together with some shots of what the soil profile looked and plant species that were put in the ground. All of the landscape photos have been taken in the direction rain water will naturally flow when it does rain i.e. from the high side looking down-slope. Thus the photos are indicative of the aspect of that particular piece of land and it will be relatively straight forward for us to take subsequent monitoring photos from approximately the same position should we choose to.

1. Crater Paddock – East
Here's the Crater Paddock - East cluster. The Weddin Mountains are coincidentally just visible on the horizon on the right hand side.

Here's the first soil profile sample. Breaking down granite toward the bottom.

Here's the second soil profile sample. Breaking down granite toward the bottom mixed with a type of light grey clay.

The plant species put into the soil in this cluster were: White Box, 2, White Cypress Pine, 1, Currawang, 1, Varnish Wattle, 3, Wedge Leaf Hopbush, 2, Western Golden Wattle, 4, Aspect SSE

2. Crater Paddock – West
Here's the Crater Paddock - West cluster. The Bogolong Hills are visible in the background.

The soil profile at this location is weathered granite but a brighter ochre colour.

The plant species put into the soil in this cluster were: White Box, 2, White Cypress Pine, 1, Currawang, 2, Hickory, 4, Varnish Wattle, 3, Wedge Leaf Hopbush, 1, Aspect SE/Flat

3. Duck Dam Paddock

The Duck Dam is visible in the background, quite full at the moment.

The soil profile at this cluster has a high clay content. In one place we noticed what seemed to be a fine salt layer at around 30 cm which immediately preceded what we call 'cement rock' - an impervious layer best described and compacted clay. It proved necessary with two of the 13 holes to use the crow-bar in order to get sufficient depth.

The plant species put into the soil in this cluster were: Grey Box, 2, Yellow Box, 1, Currawang, 3, Varnish Wattle, 4, Wedge Leaf Hopbush, 1, Western Golden Wattle, 2 Aspect North

4. Front Paddock

At the back of this view of the cluster in the Front Paddock can be seen the hill that has Lookout Rock on it, and in the mid-ground a few quite impressive Yellow Box trees.

The soil profile at this cluster was very damp heavy clay, which made for the toughest digging as it was quite labour intensive to remove the material from the auger. The above photo was taken the day after planting had occurred and some drying of the soil had occurred.

The plant species put into the soil in this cluster were: Grey Box, 2, Yellow Box, 1, Currawang, 4, Varnish Wattle, 1, Wedge Leaf Hopbush, 2, Western Golden Wattle, 3, Aspect, S

5. Plateau Paddock – East

At the rear of this cluster can be seen the trees in the gully below what is normally a dry dam, and across to the Crater Paddock.

Here you can see the coarse broken down granite sub-soil at the rear of one of the plant guards. This was particularly easy digging. Also in the photo is the mini-bull-swales created to channel runoff to the plant thus theoretically reducing the need for watering of the plants in the early stages.

The plant species put into the soil in this cluster were: White Box, 2, White Cypress Pine, 1, Currawang, 2, Varnish Wattle, 4, Wedge Leaf Hopbush, 4, Aspect, NNW

6. Plateau Paddock – West
The view from this site is similar to the last with the exception that a neighbour's Canola crop in full flower is to the right.

The soil profile was the same as for the Plateau Paddock - East site.

The plant species put into the soil in this cluster were: White Box, 2, White Cypress Pine, 1, Deane's Wattle, 2, Hickory, 4, Varnish Wattle, 1, Western Golden Wattle, 3 Aspect, NE

7. Saddle Paddock

This site is the closest to Goodes Lane and thus the easiest to see by the passing traffic.

The sub soil was wet and quite sandy. This site had an awesome number of active worms detected during digging. This augers well for future pasture health.

The plant species put into the soil in this cluster were: Grey Box, 2, Yellow Box, 1, Deane's Wattle, 2, Hickory, 3, Wedge Leaf Hopbush, 1, Western Golden Wattle, 4, Aspect, SW

8. Yabby Paddock - North

The Saddle Paddock cluster is in the background of this photo (trust me!).

This site was the driest of all, which we attribute to the impact of the contour bank slightly up-hill. In a couple of locations there was a cover of Redgrass which proved quite a challenge to dig through as the plants create a solid mass of vegetation just below the surface. The Couch Grass was also very thick at this site.

The plant species put into the soil in this cluster were: Grey Box, 2, Yellow Box, 1, Deane's Wattle, 3, Wedge Leaf Hopbush, 3, Western Golden Wattle, 4, Aspect, NNW

9. Yabby Paddock - South

A quite similar background to the other cluster in this paddock.

 This site had the most diverse sub-soil profiles of any of the 10 as the above 3 photographs show.

At one point I finished digging one of the holes and went away for a couple of minutes to retrieve another implement. On return I found this 'surprise' at the bottom of the hole. Obviously it had inadvertently entered and was unable to escape. We think it is some type of juvenile Brown Snake but someone else has suggested it might be a type of Legless Lizard. We released it to under a nearby low bush.

The plant species put into the soil in this cluster were: Grey Box, 2, Yellow Box, 1, Currawang, 2, Varnish Wattle, 3, Wedge Leaf Hopbush, 4, Western Golden Wattle, 1, Aspect, NNW

10. Yellow Box

 The above photograph was taken on disk and is not quite as clear as the others. The trees you can see to the left are in Ochre Arch gully. This site will also be visible from Goodes Lane, especially as the trees grow.

The sub-soil colour at this site is a vibrant ochre, verging on orange red. Quite stunning and very friable.

The plant species put into the soil in this cluster were: Yellow Box, 3, Currawang, 2, Deane's Wattle, 4, Varnish Wattle, 1, Wedge Leaf Hopbush, 3, Aspect, N

In Conclusion
We now look forward to watching the plants grow, and in time be used by the birds in the area. On the weekend just gone we did our first watering of the plants via natural syphon from our fire-fighting tank. In all it took about 1.5 hours and as we get better at it we expect the time to reduce to around one hour. Not bad at all, and will be important during the summer months.

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