It's quite far apart the posts on this blog right now, the reason being that we are about to finish writing the last pages of our upcoming book of forest gardening and do not have time for much else writing at the moment. At the same time, however, move a little on the frontier of forest gardening and here I want to tell about interesting reading. First came just over a month ago a items written by Johanna Björklund, Karin Eksvärd and Christina Schaffer about the participatory research project demolished around 12 pieces of timber gardens 60 sqm each which began in 2013. The article describes in detail how the plantation was designed and species included in the grove. A fun result from the study is that the participants found it a simple task to provide themselves with vitamins and minerals for much of the season from the forest garden. It has all that is in timber gardens have long known, but now there are also black and white. Another thing many are suspicious is that it is more difficult for the forest garden to provide us with proteins, fat and carbohydrates, something which the authors believe need to be examined much more to come. To read a more detailed report on the research project can be Swedish final report highly recommended.
Another new research report is written by my partner Rebecka Törnqvist. It's called Limitations and opportunities of forest gardening in the Swedish climate and the project was funded by the Royal Forestry and Agricultural Academy. The report includes both a literature study on water- and nitrogen-related issues in the Nordic forest horticulture and a presentation of the results of measurements and calculations performed here in Putt Myra forest garden. Are you interested in setting up a water- or nitrogen balance for your timber garden, you can find tips on how it can be achieved in the report. The contributions of nitrogen fixation and water balance in the forest garden that I wrote about a year ago based on Rebekah's literature, but it has been much more exciting during the work. For example, I have long wondered what are the biggest differences in growing conditions here in Dalarna, compared with, for example, Martin Crawford cultivation in southwest England or the famous woodland gardens in the northeastern US. The answer is found in the table below, which is the same as Table 6 in the report. As shown, perhaps the most important factor of the rainfall during the growing season when it comes to the comparison between the Swedish forest gardens and the North American. All three North American example, ie, Mark Shepard New Forest Farm, Ben Falk's farm in Vermont and Erik Toensmeiers urban forest garden Massachusetts receives more rainfall than the plants need optimal growth. Otherwise, the growing conditions on the basis of these parameters are essentially the same as for Holma forest garden Skane. Regarding the lush English woodland gardens we can see that they play in another league simply, Highly årsmedeltemperaturer, tremendously long growing seasons and ample rainfall, in particular Martin Crawfords fall.
Table of different culture conditions skogsträdgårdars: Precipitation (årsmedel, P year, and during the growing period, P veg), temperature årsmedel (T), vegetation period length (veg period), potential evaporation (PET) and the ratio of P veg and PET timber gardens in temperate climate zones of Europe and North America.
|Puttmyra (Dalarna)||600 a||360 a||4,3 a||180||550 a||0,65|
|Holma (Skåne)||699 a||398 a||6,9 a||210||600 a||0,66|
|Barstow (Trondheim, Norway)||884 b||519 b||5,2 b||180||600 g||0,87|
|Hart (Shropshire, UK)||668 c||504 c||9,9 c||270||550 d||0,92|
|Crawford (Devon, UK)||848 c||848 c||11,4 c||>310||600 d||1,41|
|Falk (Vermont, USA)||949 e||623 e||6,2 e||210||560 i||1,11|
|Shepard (Wisconsin, USA)||878 e||705 e||6,4 e||210||650 h||1,08|
|Toensmeier (Massachusetts, USA)||1212 e||762 e||8,7 e||210||580 i||1,31|
A Data from SMHI open climate data for 1961-1990: https://opendata-catalog.smhi.se/explore/, b Climate Data for 1982-2012: https://sv.climate-data.org/ c UK Met Office for the period 1981-2010: https://www.metoffice.gov.uk/, d Kay and Davis, 2008 for 1961-1990 , e US Climate Data for 1961-1990 http://www.usclimatedata.com f real evaporation Sanford and Selnik, 2013 for 1971-2000 g Wong och Beldring, 2011 for 1961-1990, h Cowell and Urban 2010 for 1961-1990, i Northeast regional climate centre http://www.nrcc.cornell.edu/wxstation/pet/pet for the period 1981-2010. *The growing season is defined (according to SMHI) that the period of days agent is greater than 5 ° C.
This research project is completed, but we hope to find further funding to immerse ourselves in including skogsträdgårdars potential to capture and store carbon dioxide. In anticipation of the next big project, Rebekah received a small grant from Flory Gates foundation "Peace with the Earth" to do a feasibility study on perennial green toys nutrition and their potential ability to accumulate heavy metals from the soil they are grown in. It was a question that we failed to get any response when we wrote the book Perennial vegetables: discover, Lizard, enjoy and it feels great to have come a step closer to an answer.