introduction
floristic catalogue
faunistic catalogue
contact
index
gallery 1: 2006-2012
gallery 2: 2012-
map
>> 2009 Aug 18
<< 2009 Jun 19

                         a   S T A M M E R  project              

2009 July 1 to August 7

Most of July had been very dry with temperatures often passing 30ºC and quite some wind. Only at the end of this month there was a substantial downpour of almost 25 litres of rain. This thunderstorm filled the superior pond, which had completely dried out, to some degree.
On the green roof only the succulent species of Sedum and Sempervivum seemed to have survived.

The dry superior pond. The inferior pond still contains some water.
On the right: yellow flowering Picris hieracioides.
20 July 9:52

___________

A long stay of my brother and his family on the terrain offered a nice opportunity to undertake some activities that need extra workforce: the flattening of the walls with some strong boards and the manual hoist ('tractel') and, secondly, the application of a first layer of earth plaster on the interior walls.

Most walls had suffered some degree of bulging towards the exterior. This leads not only to weaker walls but forces also the use of more earth plaster. We made loops with the steel cables and the hoist in which a combination of strong boards were fixed to supply the necessary pressure and resistance.
After tensioning the cables with the hoist, the results were quite satisfactory, although in some cases we had to redo the operation and leave the cables under tension for some days to give the straw bales the opportunity to adapt to the new situation.

The manual hoist proves to be a versatile and almost indispensable tool for correcting straw bale walls.
30 July 11:34

______________

The corners needed also some kind of surgery. As a result of compression the bales gain something in length which is inevitably transferred to the corners. A simple saw is one of the best tools to shave the corners, while just manually taking away straw from behind the strings is also effective provided you retie the strings with the help of some short wooden sticks.

______________

With the walls almost completely flat and vertical, we could start with the plastering. We used the same earth that was taken out of the ground for the foundations and the cellar. In previous tests this earth proved to contain sufficient clay. This earth is first sieved through a sieve (6 mm) to get rid of the stones and then poured onto a tarp where it is mixed with chopped straw and water. After some tests, the best mix for this first layer of plaster resulted to be: 5 (volume) parts of earth, 5 parts of chopped straw and 1 part of water. This is of course not a universal mix to be applied everywhere: it depends a lot on the quality of the clay which can be extremely variable from place to place.
The straw is chopped with a light electric version of a weedwhacker in an enclosure made of straw bales.

The most comfortable and funny way of mixing the plaster is just tramping with bare feet. Adding music and dance is recommendable of which the most efficient proved to be the cha-cha-cha.
After mixing we left the plaster some time for the clay to completely dissolve. First we left it overnight, covered with the tarp but this produced a terrible smell reminiscent of rotten potatoes, so we reduced this interval to just some hours, which didn't seem to affect the quality of the plaster.

The application of the plaster onto the walls goes best with bare hands and wetting the straw bales previously with a spray. Some parts were quite difficult to stick the plaster. In these case a very thin layer of plaster sufficed to prepare for a second layer which stuck much better.

Mixing the plaster with a Cha-cha-cha.
4 Aug 19:08

______________

The plaster can't be applied to wood so all the wooden boards and boxes have to be covered with cloth (geotextile, felt) and wire mesh. The plaster sticks very well to the metal mesh and the cloth assures that the plaster can move independently from the wood, avoiding fissures.

To fix the mesh to the straw bales the literature (and internet sources) recommend so called 'landscape pins' which are impossible to find in Spanish hardware and construction stores (a returning problem). So I improvised my own pins, using Chinese bamboo chopsticks (less than 5 eurocents per stick) and 70 mm nails.

______________

This heap of earth in the extreme south-east corner of the terrain is hiding a collection of big stones which had to be removed with a bulldozer from the border with our neighbours. I gave the hill a north/south exposure to create different ecological conditions on the two slopes. Rain will reveal little by little the surface of the rocks and hopefully improve the somewhat uninspired shape of the hill. Plant growth will be mainly spontaneous, although I will probably not be able to resist the temptation to plant some rock plants on the slopes.

introduction
floristic catalogue
faunistic catalogue
contact
index
gallery 1: 2006-2012
gallery 2: 2012-
map
>> 2009 Aug 18
<< 2009 Jun 19