Many different animals, plants, fungi and lichens live in the tree from the root to the crown. At first glance, you cannot see the individual floors of the forest. But for each layer, there are specialists who enrich the forest ecosystem. Oak can accommodate a particularly large number of organisms: around 1,000 species of beetles have been identified on tree species in Germany. And this is only a small part of the colorful life in the forest.
Oaks need foresters
Oak is considered a forest tree. Often only with the help of foresters who collected dangerous beeches in the area, they gave the oak light.
The canopy is the last floor of the forest. The canopy layer protects the plants and animals below from rain and excessive sunlight, allowing young plants to grow sheltered on the ground. At a height of up to 35 m, oak crowns are an important food and habitat for bats, birds, insects, creepers and animals such as squirrels. Small rodents do important work for natural regeneration: squirrels usually store winter supplies near their “hideouts”. It is a spherical burrow placed in the fork of a branch in which they hibernate. During this time, diurnal animals leave their burrows only to eat. However, since squirrels cannot find all the nuts and seeds hidden in the ground in many places, forgotten stocks can sprout in the spring.
Tribes full of life
Oak trunk and wood are also more mobile than it seems at first glance. Especially insects settle here. The thick and cracked bark of older oak trees provides space for the eggs and larvae of insect species that reproduce in wood and bark, such as noble beetles and longhorn beetles. Particularly rare beetles, such as the hermit beetle and oak beetle, live mainly in lying or standing dead oak wood. In special projects, such as the biotope wood strategy “Xylobius” Wald und Holz NRW, such particularly ecologically valuable trees are marked, protected and permanently preserved.
A layer of moss is at the base of the trunk. As the name suggests, mosses and lichens grow here. Occasionally, the fruiting body of the mushroom sticks out. Connected in the roots of the so-called mycorrhiza, on oaks you can find popular, for example, summer boletus, but also poisonous mortal mushrooms. There are different specialized mycorrhizal fungi for different tree species. Thanks to this combination of roots, trees and fungi exchange nutrients, among other things.
The oak’s roots protrude particularly deep into the ground, which is why foresters call them deeply rooting. This makes it less endangered in storms than tree species with shallow roots such as spruce. However, the soil serves not only to support the tree and supply water, but life of all kinds abounds here too. Branched passages of mice or badgers run through the fertile layer of humus. Earthworms go down a few meters and enrich the soil with important nutrients. In colder seasons, some reptiles and amphibians use the soft forest substrate for hibernation. Withdrawn there, they fall into stiffness.
Proven tree species
Oaks have been populating the earth for several million years. But oak is also an important tree in the forest of the future. Oaks can withstand the consequences of climate change better than many other native tree species. That is why foresters planted oaks in many forest areas damaged by bark beetles and drought. As the trees have given a lot of fruit this year, foresters are counting on a plentiful harvest of seeds in the fall. Grown in a tree nursery, the acorns grow into the next generation of forester.