- Miscellaneous: mushrooms
- Crop Production: agroforestry, biological inoculants, cover crops, irrigation, organic fertilizers
- Education and Training: demonstration, farmer to farmer, on-farm/ranch research
- Farm Business Management: agritourism, new enterprise development
- Production Systems: organic agriculture, permaculture
- Soil Management: green manures, soil analysis, soil microbiology, organic matter
The problem that Phase 1 addresses is how to alter the soil in the Ozarks which is naturally acidic to a pH of 7.5 and maintain it. In all other aspects this area of the Ozarks is very similar to the Burgundy Truffle growing areas in Europe.
The Southern Missouri Ozarks were clear-cut over 80 years ago and the forest has re-established itself as a second-generation mixed hardwood forest. Timber cutting is the main industry in the area with high pressure for clear-cutting due to the high unemployment in the area, the lack of forestry and environmental laws to restrict clear-cutting and the short-term gain obtained. The other main source of employment is the tourist-recreation business with canoeing, kayaking, hiking and camping in an area of unique natural beauty, large springs and clear streams. A sustainable Agroforestry practice producing a high value crop that would have appeal to the eco-tourism and culinary industry would be a great asset for the region, not dissimilar to the wine industry.
Working with Dr. Bruhn, Ozark Forest Mushrooms (OFM) is eager to establish a research and demonstration Burgundy Truffle Orchard to test the apparent suitability of our soil and climate, cultivation methodology and ultimately the productivity of this high value specialty crop. For this purpose, an initial 50 meter by 50 meter plot (0.25-ha, or 0.625-ac) has been selected on the mushroom farm, which will be expanded if successful. Given the 8 to 12-yr waiting period after planting until full production is achieved, we plan to use this grant to accomplish soil amendment and site preparation necessary to establish a truffle orchard consisting of a 1: 1 mixture of Burgundy truffle-colonized hybrid English oak x swamp white oak trees (Quercus robur x Q. bicolor) and European hazelnut trees (Corylus avellana) planted at a total density of 400 trees per acre.
Dr. Bruhn recommends this oak/hazel mixture for several reasons. First, the trees that we will plant once site preparation is complete will be greenhouse-colonized by the prolific and high quality Burgundy truffle source native to the Swedish Baltic island of Gotland, where English oak and the European hazelnut growing in mixture are the main habitat for the Burgundy truffle. This very productive and high quality source is well adapted to cold winters, and to soils with somewhat less clay than is the case in central Europe. Dr. Bruhn has found that the English oak x swamp white oak hybrid produced by the Forrest Keeling Nursery (Elsberry, MO) is much more resistant to powdery mildew disease than English oak, yet is also an excellent host for the Burgundy truffle. Finally, the European hazel achieves greater height at maturity than do native North American hazel species, thus producing greater and earlier shade. This is important because it has been shown that the Burgundy truffle does not fruit optimally until canopy closure has occurred.
Detailed soil tests at our selected truffle orchard site indicate an average pH (water basis) of 6.2 over the surface 20-cm (8-in), average organic matter content ranging 1.6-3.2 percent, and clay content of 12.5-20 percent. While these values are low to marginal for Burgundy truffle cultivation, they are easily and economically correctible. Soil amendment will take two forms. First, organic matter will be added both to increase soil organic matter content and CEC (cation exchange capacity), and also to serve as a soil surface application for weed control. For this purpose, we propose harvesting an invasive and prolific water plant (milfoil, Myriophyllum spp.) from our own spring fed lake, drying it during the summer in our greenhouse, shredding it and using it both un-composted as a weed mulch and composted as an organic matter soil amendment for our low clay soils. We have tested this process and the resulting product is very similar to peat-moss with a smell not unlike alfalfa. Tests at the University of Missouri Plant Testing Lab indicated a CIN ratio ranging from 14.5-16.9/1, similar to that of horse manure. Use of this material will serve four purposes: 1) removal of an invasive lake weed; 2) providing a local source of a high nitrogen soil organic matter amendment for use in the truffle orchard; 3) providing a local source of weed-barrier mulch for use in the truffle orchard, and 4) providing a local source of an organic mulch/compost in OFM's other organic gardens.
Second, in order to attain an average pH of 7.5 recommended for the Burgundy truffle, we will initially apply the equivalent of 26 Tonnes per hectare (T/ha) of crushed fine dolomite limestone to the upper 20-cm of soil. For our 5Om x 5Om (0.2S-ha2 = 0.62S-ac2) test orchard, this will require 7 tons (imperial) of fine dolomitic lime. Spring and autumn soil analyses will be conducted until pH stabilizes, at which point we will decide whether or not an additional application is advisable. Once soil pH has stabilized at roughly 7.5, we will consider incorporating limestone chips (5-20-mm dia, approx. 0.2-0.75-in) for long term pH buffering purposes. Lime sources will be balanced (white lime versus red lime, Mg concentration) in order to approach a Ca:Mg ratio of roughly 40:1 with substantial iron (Fe) content.