Design for: Het Groeilokaal. By Henk Eshuis. Online PDC 2015 given by Geoff Lawton

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1 Design for: Het Groeilokaal By Henk Eshuis Online PDC 2015 given by Geoff Lawton

2 Project description Through facebook I got in contact with Astrid Huijbregts ( who is starting a new initiative in the Netherlands, Het Groeilokaal. She was looking for people who could help with a permaculture design and I was looking for a site to design. So I took the opportunity to do the design exercise on Het Groeilokaal. Het Groeilokaal is an initiative to get the local population and especially children more involved in nature and food. My task was to design a food forest and teagarden. To the south there is a bicycle path and the idea is that people can stop there and visit the garden and food forest. The actual Groeilokaal is a circle of closely planted Pinus silvestris trees on the field to the left. The idea is that those trees will merge together over time forming a living school. The terrain is in total 18 hectare and is a former mobilization terrain (MOB) of the Dutch army. At the moment it is still property of the government. A few years ago all buildings have been demolished. Since then nature is slowly taking back the terrain. Officially this area is a protected nature area so only indigenous species can be used. For my exercise I concentrated on a smaller part of the open area you can see in the red square below of about 4000 square meter. Het Groeilokaal is situated close to the city of Tilburg, in the image above you can see the MOB terrain. The coordinates are: Latitude Longitude: , The altitude is 13,7m above sea level. The site is about 80km from the sea. The land is more or less flat. From LiDAR data I got that the terrain is between 13,6 and 13,8 m above sea level, almost perfectly flat. The only thing is that there is a small ditch around the northern part of the terrain of about,5 to 1m deep. There is no open water available.

3 The forest around the spot consist mainly of 4 tree species, Birch ( Betula pendula ), Pine ( Pinus sylvestris ), Summer oak ( Quercus robur ) and American oak ( Quercus rubra ). See the image below for a general idea. After the demolishing of the buildings there is a lot of regeneration taking place of pine and birch. Also there are some small patches of heather (Calluna vulgaris). As can be seen in the pictures below.

4 Climate: The climate in Tilburg is hardiness zone 9 (10a USDA) with minimum temperatures not getting below zero. Average rainfall is around 800mm/year and is fairly distributed over the year, see the table below. Prevailing winds are from the southwest The data below is based on registered weather data and applies to Tilburg: maximum temperature ( C) minimum temperature ( C) hours of sunshine per day days with precipitation per month mm precipitation per month sea temperature ( January n/a February n/a March n/a April n/a May n/a June n/a July n/a August n/a September n/a October n/a November n/a December n/a = 0 5 mm = 6 30 mm = mm = mm = mm = over 200 mm Source: I checked were the sun is during winter and summer with an app on my mobile phone. During winter the sun only reaches the most northern part of the open area, in high summer the sun reaches almost everywhere with the most sunshine in the northern part of the open area. This is where the most sun demanding species will be planted. Soil: Exact measurements on ph I did not do but from the site itself it is clear that the soil is very sandy, poor in nutrients and acidic. The forest surrounding the open space still contains the typical podsol, leached out topsoil. On the open space itself there are indicator (pioneer) species growing like Pinus sylvestris and Betula pendula. On several spots I did a soil test with some soil in a glass jar and shaking it and let it settle for several hours. On the right you can see the result. Practically all sand with very little organic matter. The result was the same for all the 5 samples I took. The groundwater level is around 3-4m below the surface.

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6 Zonation: Zone 1: This zone will be the central zone where most of the activities are. There is a storage place made of a sea container for equipment. A herb spiral and vegetable garden beds can be made here. This is also the place for the teagarden. From the container an extra roof will be made to be able to catch rainwater and store in one or two IBC containers. Zone 2: On the border between the first and the second zone there will be a lot of lime trees that can be coppiced. The leaves can be eaten and the drop will be used as green manure and because of the high mineral content be used against acidification of the soil. In this zone most of the grafted species are planted. Also sea buckthorns are added as nitrogen fixer. Shrub species are mainly Ribes and Rubus spp. But this can be extended. Zone 3: Here all the nut trees are situated. Italian alder is added as a nitrogen fixer, together with lime trees this should improve the soil a lot during the years. Zone 4: This zone is used as source of wood to be chipped or to be used as stems to grow mushrooms. Some oaks are growing here, nuts can be used to make oak meal. Zone 5: This zone will be left unmanaged.

7 Working plan The first phase will take place this year. As soon as possible nitrogen fixing annuals will be sown like Black medick ( Medicago lupulina ), lupine ( Lupine spp ) and comfrey ( Symphytum spp ). Black medick is especially good since it makes very deep roots, taking up minerals. Clovers don t like an acid soil, can be used later in the process. A 20 foot sea container will be placed for the storage of all the equipment and other materials. The container is placed in the north eastern corner because there the surrounding trees are lower for the water catchment and there is some sun because of that but not too much. Also the roof will be extended so you will get a space to hide for the rain. A gutter will be installed to catch the rain in one or two IBC tanks of 1000 liter. With this amount of water it should be possible to water all the plants and trees taking into account that it rains almost throughout the year. The roof area will be around 6x6=36m2, with annual rainfall of 800mm there will be around liters collected from the roof. Excess water can be led into a wadi (not a swale since there is no slope) just next to the container were it can infiltrate into the ground. The soil is poor and acidic. The soil needs a lot more organic matter. If money allows it a large quantity of compost can be brought in. At the moment there are a lot of young pine and birch trees growing in the open area. In the fall those trees will be removed and also some trees in the surrounding area will be cut (pines and birches), mainly to get some space for the walking paths. For one day a wood chipper will be rented to make woodchips out of the wood and this can be used on the pathways and surrounding newly planted trees. The pathways can be seen in the image to the right. The grey ones are to be made and the road will be kept in place. The road can be sown with clover and grass as groundcover. The path to the left will lead to the actual Groeilokaal. The path from below is the entry for visitors coming from the bicycle path. Lime will be added when the land is cleared, exact measurement and calculation of the amount needed still needs to be done.

8 When the land is cleared and the paths are in place, during (early) winter time the first trees of the canopy layer of the food forest can be planted. In the map below you can see where all the trees are planned. Out of paper I cut circles in the right proportions to resemble what the ultimate size of the trees will be, this to ensure that there is enough light for the other layers below. All sizes and information of the species are taken from the book Creating a forest garden by Martin Crawford. A list of species can be found below. Between brackets to clarify what species on the map. This list is not inclusive as there are many more edible species to be discovered. Crown layer: Fruit: Sweet cherry, Prunus avium 8m high, 6m wide Plums, Prunus domestica 6-7m high and wide Pears, Pyrus communis 8-20m high, 8m wide Apples, Malus domestica 4-5 m high and wide Hawthorns, Crataegus spp, 4-6m high, 4m wide (partly grafted with Medlar, Mespilus germanica) (HAW) Service tree, Sorbus devoniensis, 6m high and 4m wide Sea Buckthorn, hippophea spp, 3-4m high and 5m wide (Sea Buck) June berries, Amelanchier spp, 5-6m high, 3-4m wide (AME) European Elder, Sambucus nigra, 46m high and wide Nuts:

9 Hazels, Corylus spp, 5-6m high and wide Walnut, Juglans regia, 20m high, 15m wide Oak, Quercus robur, 20-30m high and wide (already present) Sweet chestnut, castanea sativa 15-20m high, 10-15m wide Pecan, Carya spp., 6m high and wide. Nitrogen fixers Italian alder, Alnus cordata, 20m high and 6m wide (ALNUS) Sea Buckthorn, hippophea spp, 3-4m high and 5m wide Leaves: Lime, Tilia spp, 4m high and wide if coppiced, also good green manure. Some will not be coppiced as a source of flowers for tea. Shrub layer Together with the canopy layer also the shrub layer can already be planted. I did not make a detailed map (yet) of all the shrubs, most of them will tolerate shade, but perform best in the sun. Ribes spp, are quite shade tolerant, planted mainly in zone 2 Rubus spp Other layers In a real food forest there can be as much as 7 layers but to sort all the species out and design them in the system will take too much time for this PDC alone. There are too many species to choose from and give a place in the 4000 m2. Also the establishment of the trees will take some time and to create the necessary microclimates for the different species. This is also best done by observing the coming years how the system develops.