The most popular Christmas tree in Denmark is the caucasian or nordmann fir. However, for some years now, trees are being hit by a condition that leads to the needles falling off the branches or unhealthy, discoloured and yellow needles, reports TV2 Nyheder.

This is estimated to cost the forestry business between 20 and 50 million kroner a year in lost revenue, particularly as Danish growers have to compete with cheaper trees from Germany and Poland.

READ ALSO: Danish exports of Christmas trees exceeds 650 million kroner

The condition is called ‘needle tip chlorosis’, and it is expected to affect around 15 percent of nordmann fir trees this year.

Something of a conundrum
However, it is hard to predict which trees are at risk.

“We see some trees in a plantation getting needle tip chlorosis, whilst others in the same row don’t get it – despite the fact they are sharing the same soil and receiving the same fertiliser,” said Ole Kim Hansen, an associate professor from the University of Copenhagen’s department of geosciences and natural resource management.

“It could indicate that some trees with a certain genome are more predisposed to the condition. For example, it is possible that the trees have different capabilities when it comes to the uptake and exploitation of magnesium.”

It is hoped that by working together with the university, growers will gain a better understanding of the physiological aspects of the trees so that the problem can be solved in the future.