The Douglas fir, which comes from North America, is quite tolerant of a lack of water for a conifer and is therefore often traded as a climate tree. In this article we will clarify how drought-resistant the Douglas fir actually is.
How drought-resistant is Douglas fir?
The Douglas fir is relatively drought-resistant because, as a heart-rooted plant, it can cope with rather dry and nutrient-poor soils. However, it is not adapted to longer dry periods and suffers from frost-dry conditions without adequate irrigation on frost-free days.
How well does Douglas fir cope with drought?
Douglas fiascope relatively well with rather dry,nutrient-poorsoils. This is because these trees are heartroot plants.
Their root system spreads quite widely, but at the same time reaches deep into the earth. This means that the storage organs can still supply the tree with water even when the soil surface has completely dried out.
How drought-resistant are Douglas firs really?
However, both their natural origin and the location requirements show that, unlike other trees, Douglas firs arenot trees adapted to longer dry periods.
- Although they are less sensitive to drought than, for example, spruces, they do not cope well with longer periods of drought in which water is scarce even in deep soil layers.
- Freshly planted Douglas firs also have to grow in very well until they can cope with a temporary lack of water.
Is frost drying dangerous for Douglas firs?
Dry frost represents abig risk for Douglas firs: If the conifers are exposed to the winter sun and the water supply is blocked by the frozen ground, they cannot absorb the moisture that has evaporated through the needles replace more. It also proves to be disadvantageous that the Douglas fir opens the stomata very early.
That's why it's important to water Douglas firs grown in the garden sufficiently on frost-free days.
Tip
Yellow needles – not necessarily a result of drought
If the needles of the Douglas fir turn yellow starting from the middle of the tree, this is not always the result of a lack of water. It is usually a fungus, the sooty thorny fungus. You can tell the difference as follows: While the buds and young leaves are shed in dry conditions, only the older needles, which also have a black underside, change color in fungal infections.
