Cowberry and soil properties. The most interesting studies proving that the red oak is a wax-invasive species.

What is its impact on wildlife?

1. Biodiversity According to the records of scientists in Poland, Slovakia and the Czech Republic, red oak plantations were floristically very poor: the average number of species next to red oak was only 17, while in forests with local species this number was on average 30-40 species. And what is important, endangered species were almost completely absent from the studied stands of red oak. More here https://bit.ly/3SC5rqZ 
2. Ecosystem services. A forest where red oak has been planted provides fewer ecosystem services, another study found.
   In this work, scientists investigated how the introduction of red oak affects the lingonberry yield. For this, data were collected from 200 research plots located in modern and older pine forests of Central Poland. Cranberry cover, shoot height, stem and leaf biomass, and, of course, fruit productivity were measured.
   The results of the study clearly indicated that where there was a red oak, it was useless to look for lingonberry berries – they were absent in both older and younger forests. https://bit.ly/3QAw6Sl
   Here it is worth adding that lingonberries are a source of food and water for birds and mammals, insects and invertebrates.
   It also means a lot to people. Trade in fresh fruits and plants collected from the wild is an important source of additional income for local communities. Collecting lingonberries in the wild is part of rural lifestyle, regional culture and traditions and an attractive form of recreation, and can contribute to the development of the local tourism industry. But all this disappears where the red oak appears in the forests.
3. Changes the natural landscape. Red oak affects forest ecosystems in a variety of ways, another study says.
   In particular, through:
   decrease in the availability of light (a thick canopy creates significant shading, which does not allow most species to survive);
   formation of a large amount of litter. The presence of Q. rubra leads to the accumulation of “litter” (undecomposed fallen leaves) on the soil surface, which creates a mechanical barrier for forest floor vegetation, especially for seed germination and seedling growth;
   change in soil properties.

The study showed that the soils under the invasive red oak (Quercus rubra) differed significantly in water-physical and physico-chemical properties. Forest litter and near-surface mineral soil horizons in red oak plantations were characterized by lower water-holding capacity, lower content of humus, nutrients (NRK), exchangeable bases, and a significantly higher C/N ratio. Thus, the replacement of natural tree species with red oak plantations leads to changes in the properties of edaphotopes, which cease to meet the needs of aboriginal soil biota and vegetation, including rare and protected species.

The study found that red oak had a negative impact on the species richness and cover of native understory vegetation, including rare and protected species. https://bit.ly/3FZ8emo
Foresters stubbornly ignore all these risks and losses, taking into account only more cubic meters of wood, which the planting of the invasive red oak species brings. Forgetting about other losses, which are much higher than profits from wood, but it is difficult to present them in the legal field of Ukraine, since “ecosystem services” are still not a subject of financial accounting.