What conditions are needed to grow wood ear mushrooms? A detailed explanation of the latest cultivation key points

Wood ear mushrooms grow on the decaying wood of more than 120 kinds of broadleaf trees, such as oak, poplar, banyan, and pagoda tree, growing in clusters and often overlapping in a roof-tile arrangement. They can also be cultivated artificially using logs and sawdust from broadleaf trees; growth requires diffused light, moisture and warmth.

Cultivation conditions for wood ear mushrooms

Wood ear mushrooms are saprophytic mesophilic fungi. The mycelium can grow at temperatures between 6 and 36°C, but 22 to 32°C is most suitable; fruiting bodies can differentiate at 15 to 27°C, but 20 to 24°C is most suitable. Lushi County in Henan Province is a case in point: its favourable natural environment has made Lushi wood ear mushroom a geographical indication protected product. The mycelium can grow in cultivation substrate and logs with a water content of 60% to 70%; when fruiting bodies form, the water content of the wood must reach more than 70%, and the relative air humidity must be 90% to 95%. The mycelium can grow normally in darkness, while the fruiting body growth period requires a light intensity of 250 to 1000 lx. It is an aerobic fungus, and pH 5 to 5.6 is most suitable.

Cultivation materials for wood ear mushrooms

Wood ear mushroom cultivation methods include log cultivation and plastic bag substitute-material cultivation, among others. Here we mainly introduce log cultivation and plastic bag substitute-material cultivation methods.

1. Log cultivation

Artificial cultivation of wood ear mushrooms originated in China around 600 AD, making it the first edible fungus species to be artificially cultivated in the world, with a history of more than 1400 years. As early as the Tang Dynasty, mountain dwellers in the Daba Mountains, Micang Mountains and Longmen Mountains of northern Sichuan used the “log cutting and scoring” method to grow wood ear mushrooms. This primitive cultivation method lasted for over a thousand years. In the Qing Dynasty, cultivation also began in the Changbai Mountains of Northeast China and the Funiu Mountains of Henan; deciduous trees were felled during the coldest days of winter, and wood ear mushrooms were bred by relying on the natural spread of spores. Harvest depended entirely on nature, and yields were extremely low.

In 1955, Chinese scientific researchers began to cultivate solid pure wood ear mushroom spawn and invented the log drilling and inoculation method, which greatly increased the yield of wood ear mushrooms in log cultivation. However, a cycle took two to three years, and the absolute yield was still not high: each high-quality log 1 m long and 10 to 13 cm in diameter produced only 100 to 150 g of wood ear mushrooms in 3 years, and production was often reduced by natural disasters. This method is still used today by only a very small number of growers in forest regions.

2. Plastic bag field cultivation

This technology changed the history of relying on wood to produce wood ear mushrooms, taking their cultivation from forest regions out into the fields. Plastic bag field cultivation of wood ear mushrooms uses sawdust and straw as raw materials, filled into plastic bags, with each bag holding 0.5 kg of dry material; after sterilization, inoculation and mycelium incubation, the bags are placed in fields and under orchard trees to produce mushrooms. The plastic bag field cultivation technique has greatly broadened the raw materials and cultivation areas for wood ear mushrooms, greatly shortened the production cycle, and, with its return-to-nature cultivation approach, delivers natural, pollution-free products; it is also more conducive to large-scale, mechanized and standardized production, with broad development prospects.

Plastic bag field cultivation of wood ear mushrooms was successfully invented by the Edible Fungus Research Institute of Chaoyang City, Liaoning Province. In 1994 it was listed in the “National Key Science and Technology Achievement Promotion Plan” and the “August 7 Poverty Alleviation Plan”; in the same year it obtained two national invention patents; in 2000 it won the “Top Ten Outstanding Scientific and Technological Achievements in the National Edible Fungus Industry”; and in 2006 it received awards and support from the World Bank, the State Council Leading Group Office of Poverty Alleviation and Development, and the Ministry of Civil Affairs. With its “from nature, back to nature” approach, plastic bag field cultivation of wood ear mushrooms conforms to the mushroom's “cold and hot, dry and wet” living habits, and offers high cultivation success rates, yields and quality, making it the mainstream of wood ear mushroom cultivation.