Some of the giant trees in Hopslia north of Holme Fjord are as much as thirty metres high. Elm and ash are the most common, basswood somewhat rarer. Relatively soft bedrock, good growing conditions and enough light, help them to thrive just here.
In the area between Eikelandsosen and Tysse, it is easy to see how the vegetation changes according to the different types of landscape forms. As a rule, pine forest dominates on the ridges and where the terrain is gently undulating. Deciduous forest is thickest on the steep slopes.
North of Holme Fjord, in the valley that runs a couple of kilometres northward from Hope and a bit into the Samnanger municipality, lies a long stretch of mountainside with deciduous forest. One of the valley sides, Hopslia, lies conveniently facing the southeast. Spring comes early here, and the plants benefit from an extra long growing season. And when the bedrock also is slatey, all the conditions are met for growing a good deciduous forest.
In addition to elm, ash and some basswood, there is also much hazel growing on the slopes; in some places it is so thick that the forest floor gets quite a lot of shade. Farthest in to the valley, grey alder dominates. The two ferns: ostrich fern and Braun's holly fern, typically occur together with a number of herbs.
Individual species have gotten a foot hold in the steep rock wall on the upper edge of the forest. More light and less competition gives them a better chance of surviving. Since birds spread the seeds, basswood has been able to put its roots down high up in the cracks in the mountainside. Trees in such places do not grow especially big, however. Hard shield ferns climb up the rock walls. Even saxifrage cotyledon manages to grow here, as long as there aren't trees to cast a shadow over them.
Hopslia is moister than most of the other deciduous forests in the county. The annual rainfall in the valley is as high as 2500 millimetres. After much rain, the forest floor can be quite wet. The water seeps off the bedrock and down into the valley, often long after it has stopped raining.
- Kolderup, N.- H. 1953. Geologi for hvermann. Hålandsdalen – Strandebarm – Kvamskogen. Bergen Turlag Årbok 1953:30-43.