30 May 2025 | Article

The contorta pine: pros & cons  

The contorta pine (Pinus contorta), sometimes called the “turbo pine”, was introduced in Sweden on a large scale during the 1970s and 1980s as a response to concerns about a future shortage of biomass. This species grows about 30% faster than the native pine (Pinus sylvestris), which made it attractive for forestry. Today, it is found on about 600,000 hectares, mainly in northern Sweden. 

An article published in February this year summarizes research from SLU (Swedish University of Agricultural Sciences) that shows that the contorta pine negatively affects several species: 

Ants: The number of anthills in contorta forests is about half compared to those in native pine forests. The dense growth pattern of the contorta pine creates darker environments, and the long needles are poor building materials for anthills. Ants also avoid searching for honeydew in contorta. 

Insects: Species that depend on ants, such as the beetle Pella humeralis, are becoming fewer. Horse ants and red ants also fare less well. 

Reindeer: Ground lichens, important for reindeer grazing, occur to a lesser extent in contorta forests, which means that reindeer avoid these areas. 

According to the SLU Species Database, contorta has a very high risk of becoming invasive, as it spreads outside planted areas – e.g. to bogs and even above the tree line. However, the Swedish Forest Agency has not classified it as invasive. So far, no major ecological problems have been observed, but this may change in a warmer climate. 

The full SLU article can be found here: